Comptia A+ Notes

• SSD (Solid-state drive)• All memory, no moving parts • Silent, fast access time, less latency • 2.5 inch and 1.8 inch form factors Hybrid drive (SSHD) • Solid-state hybrid drive • Flash memory and hard drive storage • SSD caches the hard drive data Magnetic disk • Traditional spinning drive platters

• Can be very modular • Two screws and the drive slides out • All internal • Open a cover on the back • Open the entire laptop

• SO-DIMM Small Outline Dual In-line Memory Module • Micro-DIMM Micro-Dual In-line Memory Module • Memory used in laptops and mobile devices

Place drops of ink onto a page • Pulled from a set of cartridges CMYK • Cyan, Magenta, Yellow, Key (black)

Too large for today's portable devices • Becoming difficult to find Often removable • Replace with other media Read and write CD-RW/CD-ROM and DVD-RW/DVD- ROM • In a portable device

Often built into the processor • Not upgradable Sometimes part of the system board • Again, not upgradable Some laptops have upgradeable video cards • Not the slimline models

LCD (Liquid Crystal Display) • Light and high-resolution Very, very fragile - Get a good case! Resolutions are fixed • Changes to native resolution may look blurry or not as crisp

Auto-switching or fixed input • Converts AC to DC • Input voltage - 110 volts / 220 volts DC jack on the laptop • Specific to the power supply type

Lithium-Ion (Li-ion) • Common in consumer electronics • No "memory effect" • Charging the battery diminishes capacity

Plastic • Lightweight, mobile • Durable, difficult to break • Inexpensive, cost-effective Metal • More durable than plastic • Can be more difficult to repair

Self-contained - Portable audio Not the highest quality - Very small Often stereo (L/R) - May include a subwoofer!

Proprietary • Built to fit Replacement isn't easy • Swap the entire board • Most components are on the system board

Designed for mobility • Power management Integrated features • Memory controller, video controller Not very upgradeable • Replaceable, but not upgradeable Often slower than desktops • Size and heat are disadvantages

Liquid crystal display - Light shines through liquid crystals Advantages • Lightweight • Relatively low power and relatively inexpensive Disadvantages • Black levels are a challenge • Requires separate backlight • Florescent, LED, etc. / Difficult to replace

Organic Light-Emitting Diode • Organic compound emits light when receiving an electric current Thinner and lighter • Flexible and mobile - no glass needed No backlight - The organic compound provides the light Not quite ready for laptops • Organic materials degrade over time • Decayed images can remain on the screen • More costly and power hungry than LCD

Multiple antennas - WiFi main and aux and Bluetooth Antenna wires wrap around the laptop screen

Video capture - Built-in camera and microphone Usually includes both audio and video • Specialized drivers and software

Pickup paper - Should be a single page at a time • Problems if no paper is picked up or multiple sheets are picked Should be periodically cleaned or replaced

LED-backlit LCD display • Backlight is LEDs instead of florescent • LEDs around the edge of the screen • An array of LEDs behind the screen CCFL - Cold Cathode Fluorescent Lamp • Higher voltage and power needed • Added thickness to the display • No longer a common backlight

LCD displays need a backlight • Florescent lamp to the LCD display to your eyes Some laptops have inverters - Turn DC into AC • Verify backlight - Look closely May need to replace the LCD inverter or display • Choose carefully

Use a pen-like device as input - Useful for graphical input Becoming more common on laptop / tablets / hybrids

Merge laptop and tablet input • No keyboard required, but often still available Many options for input - Use the best one for the job

Toggle Fn keys • Secondary functions • Toggle between LCD / external monitor / both LCD switch • The "refrigerator door" effect • Physical switch on older systems • Internal magnetic switch on newer portable systems • Set functionality in the BIOS or utility

Control your wireless signal • Airplane mode, secure areas • Look for a status light A physical switch or function key May include 802.11, Bluetooth, and cellular • Look for the symbol or status light

Another function key • Maybe a standalone key • Often includes a mute option Physical dial or button • May see visual feedback

Control the backlight • Secondary function keys More light, more power • Conserve your battery

An option on many laptops • See in the dark Secondary function control • Intensity • Duration • Disable

Enable and disable • Avoid inadvertent mouse clicks and movements

Rotate the screen • Useful on rotating tablet / laptops • Landscape to portrait Fn key or hotkey • Different across manufacturers

Control audio and video from your keyboard • No mouse clicking Play, stop, rewind, fast forward • Mute, volume

• Listen for GPS signals • May also be associated with airplane mode or other wireless settings

Docking station • Use an external keyboard and mouse • Extend existing laptop interfaces • Add additional functionality • Desktop adapter cards • Avoid cable issues Port replicator • Similar to a docking station • Does not have an expansion card option

Keep your laptop from walking away • The bad guys are good at this Connect to a solid object • Nothing moves Laptops include metal-reinforced locking slots • Connect to the lock

Combine a laptop keyboard with a tablet screen Presentation display May include a stylus for input

Single-screen touch computers • iOS, Android, etc. • Larger than ~7 inches diagonal Designed for touch input • Virtual keyboards, drawing interfaces Application support • Productivity, games, utility, etc. • Specialized applications Media - Take pictures, watch movies

Mobile communication • Voice, email, text, instant message, pictures, video • ~ 3.5 inches to 6 inches diagonal Media viewer - Music, movies, videos Mobile applications • Maps, travel information Other apps • Productivity, games, specialized apps, etc.

Smartwatches • An extension of your phone and body Fitness monitors • Track heart rate, steps, sleep patterns, and more

Replace reality with a computer-generated version • Input from the real world interacts with the virtual world Many different application • Gaming, industrial design, art • Enhanced video and image viewing

Overlay a virtual augmentation with the physical world • The computer provides additional detail Used in medical, travel, gaming

Specialized device • Book reading - Some music, some apps Electronic paper • Black and white screen • Performs well indirect light • Exceptionally long battery life Network access - WiFi, cellular

• In-car navigation (and non-car) • Requires a view of the sky - Need to receive GPS signal • Periodic updates required Over the air and memory card

EU standardized on Micro-USB • Common now worldwide Older devices may use Mini-USB • Slightly larger

24-pin double-sided USB connector • Used for both hosts and devices Acts as a USB 3.1 / USB 2.0 connection • Only the interface is different Includes an analog audio option • Headset support through a 3.5 mm jack

Apple proprietary • 8-pin digital signals • iPhone, iPad, iPod devices Some advantages over Micro-USB • Higher power output for phones and tablets • Can be inserted either way • Simpler design, more durable

Physically connect a device to your mobile phone • Use the Internet/data connection Enable Internet access from almost anywhere • May require service or configuration by wireless carrier

Early mobile technology was all about cables • One cable for power • A completely different cable for data Every manufacturer was different - Intentionally The EU changed things • Common external power supply for all data-enabled mobile phones sold in the European Union

Send small amounts of data wirelessly over a limited area • Built into your phone • Payment systems, transportation, in-person information exchange Access token, identity "card" • Short range with encryption support

• Hands-free audio - Earphones and microphone Wired • Connects to TRRS connector (Tip-Ring-Ring-Sleeve) • Wireless - Bluetooth headsets

Pull just the top sheet from the paper tray • Not multiple sheets • Small and inexpensive - Easy to clean or replace

Internet of Things networking • Open standard - IEEE 802.15.4 PAN • Alternative to WiFi and Bluetooth • Longer distances than Bluetooth • Less power consumption than WiFi Mesh network of all Zigbee devices in your home • Light switch communicates to light bulbs • Tell Amazon Echo to lock the door Uses the ISM band • Industrial, Scientific, and Medical • 900 MHz and 2.4 GHz frequencies in the US

Turn your phone into a WiFi hotspot • Your own personal wireless router • Extend the cellular data network to all of your devices Dependent on phone type and provider • May require additional charges and data costs

Included on many smartphones, tablets, and smartwatches • Not really used for file transfers and printing Control your entertainment center • Almost exclusively IR

Gaming console feel - Mobile phone or tablet Connect with Bluetooth - Wireless connectivity

Power is key - And in short supply • Swappable battery pack • Carry an extra or two External USB charger • Phones and tablets • And any other USB devices

Screen protector • Avoid scratches • May be difficult to install Device protector • Wrap the entire device • Waterproofing options are available • Can create problems for docking stations

Phone or tablet becomes a point of sale terminal • Connections to audio/mic TRRS jack • Great for small and mobile businesses Uses the Internet link for approvals • Immediate feedback Additional features• Email receipts • Sign with your finger

Increase storage capacity of smartphone or tablet • Common on Android devices • Not available on iOS devices MicroSD cards • Small form factor, with increasing capacities

Your phone has an Internet connection • Use your mobile provider network • Take advantage of this connectivity Hotspot • Turn your phone into a WiFi Router • You may have to pay extra phone charges • Other devices connect to your phone via WiFi

Enable and disable cellular, WiFi, and Bluetooth independently • Airplanes, conserve battery • iOS - Settings / Cellular • Android - Settings / Wireless & network settings

Enable Bluetooth on both devices • Android and iOS: Settings / Bluetooth Set devices to discoverable mode • May require key sequence on Bluetooth device Select discovered device • Many devices may appear! Enter or confirm the PIN • Should be the same on both devices Test connectivity • Devices should now communicate

Baseband radio processor • A network interface for your radio • This isn't WiFi or Bluetooth Has its own firmware and memory • Quite proprietary Real-time operating system • Everything happens very quickly as needed The firmware can be updated • Over the air (OTA) • Invisible to the end user

PRL updates • Preferred Roaming List • CDMA networks (i.e., Verizon, Sprint) • Allows your phone to connect to the right tower • Can be updated over the air (OTA) PRI updates • Product Release Instructions • Radio settings - ID numbers, network codes, country codes, etc • Also updated over the air

International Mobile Station Equipment Identity Identifies a physical mobile device Every phone has a different IMEI Can be used to allow or disallow access

International Mobile Subscriber Identity Identifies the user of a mobile network Can be provisioned in the SIM card Swap the SIM to move between phones

Turn your phone into a VPN endpoint • Important for secure communication Integrated into the phone OS • No additional software required May require some additional setup • Detailed configuration settings May support multifactor authentication • RSA SecureID

Retrieving mail - POP3, IMAP Sending mail - SMTP Corporate email - Microsoft Exchange Integrated providers •iCloud, Google, Exchange Online, Yahoo

Post Office Protocol 3 (POP3) • Used for downloading mail to a local mail client • Downloads and (optionally) deletes from server Configuration information • Name of POP3 server • Username and password Network ports • Defined by your mail provider • POP3: tcp/110 • SSL (Secure Socket Layer) settings - POP3S: tcp/995 Internet Message Access Protocol (IMAP4) • Access mail on a central server, • Mail is usually stored on the server • Supports folders and server-side searching Configuration information • Name of the IMAP server • Username and password Network ports • Defined by your mail provider • IMAP: tcp/143 • SSL (Secure Socket Layer) settings - IMAPS: tcp/993

SMTP - Simple Mail Transfer Protocol Send mail from a device to a mail server • Or between mail servers • You usually must send from a local or trusted device Authentication usually required • Maybe different credentials than the incoming mail Port numbers • SMTP (no authentication, relatively unused): tcp/25 • SMTP with authentication: tcp/587

Enterprise email • Not a service for the home More than just email • Contacts, Calendars, Reminders Integrates with mobile device database • Integrated contacts, calendars, etc Configuration options • Email, server, domain, username, password Integrated message encryption with S/MIME • Secure/Multipurpose Internet Mail Extensions • Encrypt and digitally sign

Gmail • Google email, splits inbox into tabs, IMAP4, POP3 Exchange Online (hosted email) • IMAP4 and POP3 support iCloud Mail - Apple Mail, IMAP4 support only Yahoo Mail - IMAP4 and POP3 support

No single desktop • Many different devices Complete mobility • Access anything from anywhere Many different types of data • Email, calendar, apps, etc All devices must stay synchronized • Most of it is invisible to us Mutual authentication • The client and server must authenticate with each other

• Contacts • Applications • Email • Pictures, music, video • Calendar • Bookmarks • Documents • Location data • Social media data • eBooks • Passwords

Completely hands-off • No physical cables, no local files • May be integrated into your • Exchange or Gmail • Choose provider network and/or Wi-Fi Apple iOS • Sync all data types to iCloud • Complete backup and recovery Android • Configure your Google account

Application requirements - OS and disk space Operating System • Mac, Windows • Synchronize to the desktop • Relatively modern versions Memory - Relatively minimal Storage space • Enough to store backups, video, pictures • You'll need quite a bit iOS • Apple iTunes - syncs everything in the phone • Creates full backups on the computer Android • Syncs online with Google • Use third-party apps like doubleTwist to transfer movies and music

Connect to your automobile over Bluetooth or wired cable • Extends the phone functionality into the vehicle Display maps, control phone calls, play music • Big display screen, keep hands on the wheel iOS CarPlay, Android Auto • Synchronizes contact information, music, and other details • Shares phone information in real-time • This could be a security issue in a rental car

iOS • USB - Proprietary (30-pin or 8-pin Lightning) • USB-C • 802.11 wireless • Mobile network Android • USB Micro-B • USB-C • 802.11 wireless • Mobile network

Efficiently move large amounts of data • Use a shipping truck The network topology is the road • Ethernet, DSL, cable system The truck is the Internet Protocol (IP) • We've designed the roads for this truck The boxes hold your data • Boxes of TCP and UDP Inside the boxes are more things • Application information

Transported inside of IP • Encapsulated by the IP protocol Two ways to move data from place to place • Different features for different applications OSI Layer 4 • The transport layer Multiplexing • Use many different applications at the same time • TCP and UDP

Connection-oriented • A formal connection setup and close "Reliable" delivery• Recovery from errors • Can manage out-of-order messages or retransmissions Flow control • The receiver can manage how much data is sent

No respond back

Connectionless • No formal open or close to the connection "Unreliable" delivery • No error recovery • No reordering of data or retransmissions No flow control • Sender determines the amount of data transmitted

The IP delivery truck delivers from one (IP) address to another (IP) address • Every house has an address, every computer has an IP address Boxes arrive at the house / IP address • Where do the boxes go? • Each box has a room name Port is written on the outside of the box • Drop the box into the right room

IPv4 sockets - Server IP address, protocol, server application port number • Client IP address, protocol, client port number Non-ephemeral ports - permanent port numbers • Ports 0 through 1,023 • Usually on a server or service Ephemeral ports - temporary port numbers • Ports 1,024 through 65,535 • Determined in real-time by the client

TCP and UDP ports can be any number between 0 and 65,535 Most servers (services) use non-ephemeral (not-temporary) port numbers • This isn't always the case • It's just a number Port numbers are for communication, not security Service port numbers need to be "well known" TCP port numbers aren't the same as UDP port numbers

tcp/20 (active mode data), tcp/21 (control) • Transfers files between systems Authenticates with a username and password • Some systems use a generic/anonymous login Full-featured functionality • List, add, delete, etc.

Encrypted communication link - tcp/22 • Looks and acts the same as Telnet

• Telnet - Telecommunication Network - tcp/23 • Login to devices remotely • Console access • In-the-clear communication • Not the best choice for production systems

Server to server email transfer - tcp/25 Also used to send mail from a device to a mail server • Commonly configured on mobile devices and email clients Other protocols are used for clients to receive email • IMAP, POP3

Converts names to IP addresses - udp/53 • www.professormesser.com = 162.159.246.164 These are very critical resources • Usually multiple DNS servers are in production

Hypertext Transfer Protocol - tcp/80 • Communication in the browser • And by other applications In the clear or encrypted - HTTPS - tcp/443 • Supported by nearly all web servers and clients

Receive emails from an email server • Authenticate and transfer POP3 - Post office Protocol version 3 - tcp/110 • Basic mail transfer functionality IMAP4 • Internet Message Access Protocol v4 - tcp/143 • Includes management of email inbox from multiple clients

Share a desktop from a remote location over tcp/3389 Remote Desktop Services on many Windows versions Can connect to an entire desktop or just an application Clients for Windows, macOS, Linux, Unix, iPhone, Android, and others

Protocol used by Microsoft Windows • File sharing, printer sharing • Also called CIFS (Common Internet File System) Using NetBIOS over TCP/IP • udp/137 - NetBIOS name services (nbname) • udp/138 - NetBIOS datagram service (nbdatagram) • tcp/139 - NetBIOS session service (nbsession) Direct over tcp/445 (NetBIOS-less) • Direct SMB communication over TCP without the NetBIOS transport

File services in macOS • tcp/548 Works with SLP (Service Location Protocol) • tcp/427 and udp/427 • Populates the list of available devices File management • Copy, move, delete files

Automated configuration of IP address, subnet mask and other options • udp/67, udp/68 • Requires a DHCP server • Server, appliance, integrated into a SOHO router, etc Dynamic / pooled • IP addresses are assigned in real-time from a pool • Each system is given a lease and must renew at set intervals DHCP reservation • Addresses are assigned by MAC address in the DHCP server • Quickly manage addresses from one location

tcp/389 Store and retrieve information in a network directory • Commonly used in Microsoft Active Directory

Gather statistics from network devices • Queries: udp/161 • Traps: udp/162 v1 - The original • Structured tables, in-the-clear v2 - A good step ahead • Data type enhancements • Bulk transfers, still in-the-clear v3 - A secure standard • Message integrity • Authentication, encryption

tcp/20, tcp21 File Transfer Protocol Sends and receives files between systems

tcp/22, Secure Shell, Encrypted Console Access

tcp/23 TelecommunicaCon Network Insecure console access

tcp/25 Simple Mail Transfer Protocol Transfer email between mail servers

udp/53, tcp/53 Domain Name System Convert domain names to IP addresses

port: tcp/80 name: Hypertext Transfer Protocol Web server communication

tcp/443 Hypertext Transfer Protocol Secure Web server communication with encryption

tcp/110 Post Office Protocol version 3 Receive email into a email client

tcp/143 Internet Message Access Protocol v4 A newer email client protocol

tcp/3389 Remote Desktop Protocol Graphical display of remote devices

udp/137 NetBIOS name service Register, remove, and find Windows services by name

tcp/139 NetBIOS session service Windows connection-oriented data transfer

tcp/445 Server Message Block Windows file transfers and printer sharing

tcp/548 Apple Filing Protocol Mac OS file transfers

tcp/389 Lightweight Directory Access Protocol Directory services

udp/161 Simple Network Management Protocol Gather metrics and manage network devices

The fundamental network device • Every device on the network has a NIC • computers, servers, printers, routers, switches, phones, tablets, cameras, etc Specific to the network type • Ethernet, WAN, wireless, etc Often built-in to the motherboard • Or added as an expansion card Many options • Single port, multi-port, copper, fiber

Receive signal, regenerate, resend • No forwarding decisions to make Common use • Boost copper or fiber connections • Convert one network media to another • Extend wireless network reach

"Multi-port repeater" • Traffic going in one port is repeated to every other port Everything is half-duplex Becomes less efficient as network speeds increase 10 megabit / 100 megabit Difficult to find today

Imagine a switch with two to four ports • Makes forwarding decisions in software Connects different physical networks • Can connect different topologies • Gets around physical network size limitations / collisions Distributes traffic based on MAC address A modern bridge is a wireless access point • Bridges wired Ethernet to wireless

Bridging done in hardware • Application-specific integrated circuit (ASIC) • Forwards traffic based on data link address Many ports and features • The core of an enterprise network • May provide Power over Ethernet (PoE) Multilayer switch - Includes routing functionality

Very few configuration options • Plug and play Fixed configuration • No VLANs Very little integration with other devices • No management protocols Low price point • Simple is less expensive

VLAN support • Interconnect with other switches via 802.1Q Traffic prioritization • Voice traffic gets a higher priority Redundancy support • Spanning Tree Protocol (STP) External management • Simple Network Management Protocol (SNMP) Port mirroring • Capture packets

Routes traffic between IP subnets • Makes forwarding decisions based on IP address • Routers inside of switches sometimes called "layer 3 switches" Often connects diverse network types • LAN, WAN, copper, fiber

Not a wireless router • A wireless router is a router and a WAP in a single device WAP is a bridge • Extends the wired network onto the wireless network • Makes forwarding decisions based on MAC address

Centralized management of WAPs • A single "pane of glass" Management functions • Deploy new access points • Performance and security monitoring • Configure and deploy changes to all sites • Report on access point use Usually a proprietary system • The wireless controller is paired with the access points Can also be cloud-based • Manage the console from anywhere

Filters traffic by port number • OSI layer 4 (TCP/UDP) • Some firewalls can filter through OSI layer 7 Can encrypt traffic into/out of the network • Protect your traffic between sites Can proxy traffic • A common security technique Most firewalls can be layer 3 devices (routers) • Usually sits on the ingress/egress of the network

Broadband • Transmission across multiple frequencies • Different traffic types Data on the "cable" network • DOCSIS (Data Over Cable Service Interface Specification) High-speed networking • 4 Mbits/s through 250 Mbits/s are common • Gigabit speeds are possible Multiple services • Data, voice

ADSL (Asymmetric Digital Subscriber Line) • Uses telephone lines Download speed is faster than the upload speed (asymmetric) • ~10,000 foot limitation from the central office (CO) • 52 Mbit/s downstream / 16 Mbit/s upstream are common • Faster speeds may be possible if closer to the CO

BRI - Basic Rate Interface (2B+D) • Two 64 kbit/s bearer (B) channels • One 16 kbit/s signaling (D) channel PRI - Primary Rate Interface • Delivered over a T1 or E1 • T1 - 23B + D• E1 - 30B + D + alarm channel • Commonly used as connectivity from the PSTN to large phone systems (PBX)

Power provided on an Ethernet cable • One wire for both network and electricity • phones, cameras, wireless access points • Useful in difficult-to-power areas Power provided at the switch • Built-in power - Endspans • In-line power injector - Midspans

Power over Ethernet • Commonly marked on the switch or interfaces

Also called Power-line communication (PLC) • IEEE standard 1901 500 megabits per second • Standard includes links to the premise, intra-building networking, vehicles, smart energy devices, and more

An all-in-one device • Modem, router, switch, wireless AP, firewall, etc

Routing to the outside world • WAN / DSL port Switching local devices • One VLAN / LAN1, LAN2, LAN3, LAN4, etc Not much to configure • Routes and switches by default

Enable/disable frequencies • 2.4 GHz and/or 5 GHz • Available options will depend on the wireless standard used Configure an SSID • May need a separate SSID for each frequency Security mode • WPA2, preferably • Pre-shared key or Enterprise Channel / channel bandwidth • Automatic / other nearby networks

WAN interface • Automatically assigned via DHCP from the ISP • May require authentication LAN interface • Internal IP address and subnet mask of the router • DHCP address range for other devices • DNS server addresses

Wired • May not have many options • Ports configured for auto speed and duplex • Speed: 10/100/1000 • Duplex: Half/Full Wireless • Enable/disable

Automatic • Auto speed and duplex • DHCP addressing End-user device configures based on router • IP address • Subnet mask • Default gateway • DNS servers

Internet of Things Home automation, mostly wireless • Security is an issue Devices • Thermostat • Light switches • Security cameras • Door locks • Voice-enabled smart speakers / digital assistants Almost all devices communicate outbound • No special port-mapping or NAT configurations required

Every SOHO router is also a firewall • No external device can directly access the internal network • This normally can't be disabled DMZ ports can be configured to allow unrestricted access • This is almost always a bad idea • Consider creating more specific port forwarding rules • Or perhaps don't allow any access

It is estimated that there are over 20 billion devices connected to the Internet (and growing) • IPv4 supports around 4.29 billion addresses The address space for IPv4 is exhausted • There are no available addresses to assign How does it all work? • Network Address Translation This isn't the only use of NAT • NAT is handy in many situations

For SOHO devices, this is automatic • Source NAT, also called PAT (Port Address Translation) • All internal devices are translated to a single external address

24x7 access to a service hosted internally • Web server, gaming server, security system, etc External IP/port number maps to an internal IP/port • Does not have to be the same port number Also called Destination NAT or Static NAT • Destination address is translated from a public IP to a private IP • Does not expire or timeout • Port forwarding

Allows network devices to automatically configure and find other network devices • Zero-configuration Applications on the internal network can open inbound ports using UPnP • No approval needed • Used for many peer-to-peer (P2P) applications The best practice would be to disable UPnP • Only enable if the application requires it • And maybe not even then

Content filtering, IP address ranges • Or a combination Whitelisting • Nothing pass through the firewall unless it's approved • Very restrictive Blacklisting • Nothing on the "bad list" is allowed • Specific URLs • Domains • IP addresses

Media Access Control • The "hardware" address Limit access through the physical hardware address • Keeps the neighbors out • Additional administration with visitors Easy to find working MAC addresses through wireless LAN analysis • MAC addresses can be spoofed • Free open-source software Security through obscurity

Configure for the highest encryption possible • WPA2-AES • Choose WPA2 over WPA • WEP is not an appropriate option Check your devices • Not all of them may allow for the highest encryption Use an open frequency • Some access points will automatically find good frequencies

Change the priority of your traffic • Voice is high, World of Warcraft is low • Or vice-versa Prioritize applications, ports, or MAC addresses • A feature of high-end SOHO routers Be careful • You could accidentally cause applications to slow down

Wireless networking (802.11) • Managed by the IEEE LAN/MAN Standards Committee (IEEE 802) Many updates over time • Check with IEEE for the latest The Wi-Fi trademark• Wi-Fi Alliance handles interoperability testing

One of the original 802.11 wireless standards • October 1999 Operates in the 5 GHz range 54 megabits per second (Mbit/s) Smaller range than 802.11b • Higher frequency is absorbed by objects in the way • Many rules-of-thumb calculate 1/3rd the range of 802.11b or 802.11g

Also an original 802.11 standard - October 1999 Operates in the 2.4 GHz range 11 megabits per second (Mbit/s) Better range than 802.11a • Less absorption problems More frequency conflict • Baby monitors, cordless phones, microwave ovens, Bluetooth

An "upgrade" to 802.11b - June 2003 Operates in the 2.4 GHz range 54 megabits per second (Mbit/s) • Same as 802.11a (but a little bit less throughput) Backwards-compatible with 802.11b Same frequency conflict problems as 802.11b

The update to 802.11g, 802.11b, and 802.11a • October 2009 Operates at 5 GHz and/or 2.4 GHz • 40 MHz channel widths 600 megabits per second (Mbit/s) • 40 MHz mode and 4 antennas 802.11n uses MIMO • Multiple-input multiple-output • Multiple transmit and receive antennas

Approved in January 2014 • Significant improvements over 802.11n Operates in the 5 GHz band • Less crowded, more frequencies (up to 160 MHz channel bandwidth) • Increased channel bonding - Larger bandwidth usage • Denser signaling modulation - Faster data transfers Eight MU-MIMO streams • Twice as many streams as 802.11n • Nearly 7 gigabits per second

Frequency • 2.4 GHz or 5 GHz (and sometimes both) Channels • Groups of frequencies, numbered by the IEEE • Non-overlapping channels would be necessary Bandwidth • Amount of frequency in use • 20 MHz, 40 MHz, 80 MHz, 160 MHz

• 802.11a - 20 MHz • 802.11b - 22 MHz • 802.11g - 20 MHz 802.11n • 20 MHz or 40 MHz (two contiguous 20 MHz bonded channels) • In 2.4 GHz, a 40 MHz channel uses much of the available bandwidth 802.11ac • 40 MHz for 802.11n stations • 80 MHz required for 802.11ac stations • 160 MHz optional (contiguous channels or non-contiguous bonded channels

High speed communication over short distances • PAN (Personal Area Network) Connects our mobile devices • Smartphones • Tethering and file transfers • Headsets and headphones • Health monitors • Automobile and phone integration • Smartwatches • External speakers

Two-way wireless communication • Builds on RFID, which is mostly one-way Payment systems • Major credit cards • Online wallets Bootstrap for other wireless • NFC helps with Bluetooth pairing Access token, identity "card" • Short range with encryption support

It's everywhere • Access badges • Inventory/Assembly line tracking • Pet/Animal identification • Anything that needs to be tracked Radar technology • Radio energy transmitted to the tag • RF powers the tag, ID is transmitted back • Bidirectional communication • Some tag formats can be active/powered

Proprietary home automation networking • Internet of Things (IoT) • Control lights, locks, garage doors, etc. Wireless mesh networking • Nodes can hop through other nodes on the way to the destination Uses the ISM band • Industrial, Scientific, and Medical • 900 MHz frequencies in the US • No conflicts with 802.11

Mobile devices • "Cell" phones Separate land into "cells" • Antenna coverages a cell with certain frequencies 2G networks • GSM - Global System for Mobile Communications • CDMA - Code Division Multiple Access Poor data support • Originally used circuit-switching • Minor upgrades for some packet-switching

3rd Generation • Introduced in 1998 Upgraded data connectivity over 2G • Incremental 3G updates improved speeds • Usually several megabits per second Bandwidth improvement allowed new functionality • GPS • Mobile television • Video on demand • Video conferencing

Long Term Evolution (LTE) • A "4G" technology • Converged standard (GSM and CDMA providers) • Based on GSM and• EDGE (Enhanced Data Rates for GSM Evolution) • Standard supports download rates of 150 Mbit/s LTE Advanced (LTE-A) • Standard supports download rates of 300 Mbit/s

Update to 4G - Rollout in late 2018 and 2019 • Worldwide launches in 2020 Significant performance improvements • At higher frequencies• May not be as significant at lower frequencies Technology updates • Additional frequencies • Improved data transmission methods

Respond to browser requests • Using standard web browsing protocols - HTTP/HTTPS • Pages are built with HTML, HTML5 Web pages are stored on the server • Downloaded to the browser • Static pages or built dynamically in real-time

Centralized storage of documents, spreadsheets, videos, pictures, and any other files Standard system of file management • SMB (Server Message Block) • Apple Filing Protocol (AFP), etc The front-end hides the protocol • Copy, delete, rename, etc.

Connect a printer to the network • Provide printing services for all network devices May be software in a computer • Computer is connected to the printer May be built-in to the printer • Network adapter and software Uses standard printing protocols • SMB (Server Message Block) • IPP (Internet Printing Protocol) • LPD (Line Printer Daemon)

Dynamic Host Configuration Protocol • Automatic IP address configuration Very common service • Available on most home routers Enterprise DHCP will be redundant • Usually running on central servers

Domain Name System • Convert names to IP addresses • And vice versa Distributed naming system • The load is balanced across many different servers Usually managed by the ISP or enterprise IT department • A critical resource

An intermediate server • Client makes the request to the proxy • The proxy performs the actual request • The proxy provides results back to the client Useful features • Access control, caching • URL filtering, content scanning

Store your incoming mail • Send your outgoing mail Usually managed by the ISP or the enterprise IT department • A complex set of requirements Usually one of the most important services • 24 x 7 support

Login authentication to resources • Centralized management Almost always an enterprise service • Not required on a home network • Usually a set of redundant servers • Always available • Extremely important service

Security Information and Event Management • Logging of security events and information Security alerts • Real-time information Log aggregation and long-term storage • Usually includes advanced reporting features Data correlation • Link diverse data types Forensic analysis • Gather details after an event

Standard for message logging • Diverse systems, consolidated log Usually a central logging receiver • Integrated into the SIEM You're going to need a lot of disk space • No, more. More than that WORM drive technology • Write Once Read Many - DVD-R • Protect important security logs

Network-based Intrusion Detection System / Intrusion Prevention System Intrusions • Exploits against operating systems, applications, etc • Buffer overflows, cross-site scripting, other vulnerabilities Detection vs. Prevention • Detection - Alarm or alert • Prevention - Stop it before it gets into the network

Next-generation firewall, Unified Threat Management (UTM) / Web security gateway • URL filter / Content inspection • Malware inspection, spam filter, CSU/DSU, router, switch, firewall, IDS/IPS, bandwidth shaper, VPN endpoint

Manage all devices from one pane of glass • Software installations, driver installations, software updates, security patches, remote troubleshooting Requires an agent on the device • Server sends the commands • Agent executes the commands

Legacy systems • Another expression for "really old" • May also be "really important" • Learning old things can be just as important as learning the new things Embedded systems • Purpose-built device • Not usual to have direct access to the operating system • Alarm system, door security, timecard system

IPv4 is the primary protocol for everything we do • You probably won't configure anything else • IPv6 is slowly appearing

• Internet Protocol version 4 • OSI Layer 3 address

Internet Protocol v6 - 128-bit address • 340,282,366,920,938,463,463,374,607,431,768,211,456 addresses (340 undecillion) • 6.8 billion people could have 5,000,000,000,000,000,000,000,000,000 addresses each

IP Address, e.g., 192.168.1.165 • Every device needs a unique IP address Subnet mask, e.g., 255.255.255.0 • Used by the local device to determine its subnet • The subnet mask isn't (usually) transmitted across the network Default gateway, e.g., 192.168.1.1 • The router that allows you to communicate outside of your local subnet • The default gateway must be an IP address on the local subnet

Uses common SSL/TLS protocol (tcp/443) • Avoids running into most firewall issues No big VPN clients • Usually remote access communication Authenticate users • No requirement for digital certificates or shared passwords (like IPSec) Can be run from a browser or from a (usually light) VPN client • Across many operating systems

It is estimated that there are over 20 billion devices connected to the Internet (and growing) • IPv4 supports around 4.29 billion addresses The address space for IPv4 is exhausted • There are no available addresses to assign How does it all work? • Network Address Translation This isn't the only use of NAT • NAT is handy in many situations

Local Area Networks A group of devices in the same broadcast domain

Virtual Local Area Networks • A group of devices in the same broadcast domain • Separated logically instead of physically

Also called "remote access VPN" • Requires software on the user device• May be built-in to existing operating system

Broadband • Transmission across multiple frequencies • Different traffic types Data on the "cable" network • DOCSIS (Data Over Cable Service Interface Specification) High-speed networking • 4 Mbits/s through 250 Mbits/s are common • Gigabit speeds are possible Multiple services - data, voice

Network with voice telephone lines • Analog lines with limited frequency response 56 kbit/s modems • Compression up to 320 kbit/s Relatively slow throughput • Difficult to scale Legacy systems, network utility • May be difficult to find a modem

Fiber optics to the home - high speed networking Converged services - Voice, Video, Data Enhanced features • Hundreds of HD channels • 1 Gbit/sec Internet access • 1 Terabyte of cloud storage • 2 Terabyte DVR

Communication to a satellite • Non-terrestrial communication High cost relative to terrestrial networking • 50 Mbit/s down, 3 Mbit/s up are common • Remote sites, difficult-to-network sites High latency - 250 ms up, 250 ms down High frequencies - 2 GHz • Line of sight, rain fade

Line-of-sight • Visual path between antennas - high frequencies Common in metropolitan areas • Cover many homes simultaneously Also options for non-line-of-sight - lower frequencies WiMAX networking • Worldwide Interoperability for Microwave Access • Wireless high-speed Internet access

Local Area Network - Local is relative A building or group of buildings • High-speed connectivity Ethernet and 802.11 wireless • Any slower and it isn't "local"

Wide Area Network - Spanning the globe Generally connects LANs across a distance • And generally much slower than the LAN Many different WAN technologies • Point-to-point serial, MPLS, etc. - Terrestrial and non-terrestrial

Personal Area Network • Your own private network • Bluetooth, IR, NFC Automobile • Audio output • Integrate with phone Mobile phone • Wireless headset Health • Workout telemetry, daily reports

Wireless mesh network • All devices connect together • A mesh "cloud" Self form - Connects to each other automatically Self-heal - Reacts automatically to changes Many different network technologies • 802.11, Zigbee, Z-Wave, etc

"Pinch" the connector onto a wire • Coaxial, twisted pair, fiber Connect the modular connector to the Ethernet cable • The final step of the process Metal prongs are pushed through the insulation The plug is also permanently pressed onto the cable sheath

Get a good crimper • And a good pair of electrician's scissors / cable snips • And a good wire stripper Make sure you use the correct modular connectors • Differences between wire types Practice, practice, practice • It won't take long to become proficient

AC voltage • Check wall outlet voltage DC voltage • PC power supply output voltages • CMOS battery power Continuity • Cable connectivity • Fuse status

Where does that wire go? • Follow the tone Tone generator • Puts an analog sound on the wire Inductive probe • Doesn't need to touch the copper • Hear through a small speaker

Easy wire tracing • Even in complex environments Connect the tone generator to the wire • Modular jack, coax, punch down connectors Use the probe to locate the sound • The two-tone sound is easy to find

Relatively simple • Continuity test Can identify missing pins • Or crossed wires Not usually used for frequency testing • Crosstalk, signal loss, etc.

Useful for testing physical ports • Or fooling your applications Serial / RS-232 (9 pin or 25 pin) Network connections • Ethernet, T1, Fiber These are not cross-over cables

"Punch" a wire into a wiring block • 66 block • 110 block Can be tedious • Every wire must be individually punched Trims the wires during the punch • Very efficient process

Organization is key • Lots of wires • Cable management Maintain your twists • Your Category 6A cable will thank you later Document everything • Written documentation, tags, graffiti

Wireless networks are incredibly easy to monitor • Everyone "hears" everything Purpose-built hardware or mobile device add-on • Specializes in 802.11 analysis Identify errors and interference • Validate antenna location and installation

Fundamental to network communication • Incredibly important foundation Usually only get one good opportunity at building your cabling infrastructure • Make it good! The vast majority of wireless communication uses cables • Unless you're an amateur radio operator

Balanced pair operation • Two wires with equal and opposite signals • Transmit+, Transmit- / Receive+, Receive- The twist is the secret! • Keeps a single wire constantly moving away from the interference • The opposite signals are compared on the other end • Pairs in the same cable have different twist rates

Electronic Industries Alliance (EIA) • Alliance of trade associations, develops standards for the industry • Standards start with RS-# (Recommended Standard) or EIA-# • http://www.eia.org Telecommunications Industry Association (TIA) • Standards, market analysis, trade shows, government affairs, etc • ANSI/TIA/EIA-568 - Commercial Building Telecommunications Cabling Standard • http://www.tiaonline.org International ISO/IEC 11801 cabling standards • Defines classes of networking standards

Traditional cable jacket • Polyvinyl chloride (PVC) Fire-rated cable jacket • Fluorinated ethylene polymer (FEP) or low-smoke polyvinyl chloride (PVC) Plenum-rated cable may not be as flexible • May not have the same bend radius Worst-case planning • Important concerns for any structure

UTP (Unshielded Twisted Pair) • No additional shielding • The most common twisted pair cabling STP (Shielded Twisted Pair) • Additional shielding protects against interference • Shield each pair and/or the overall cable • Requires the cable to be grounded • Unshielded and shielded cable Abbreviations • U = Unshielded • S = Braided shielding • F = Foil shielding (Overall cable) / (individual pairs)TP • Braided shielding around the entire cable and foil around the pairs is S/FTP • Foil around the cable and no shielding around the pairs is F/UTP

Two or more forms share a common axis • RG-6 used in television/digital cable • And high-speed Internet over cable • RG-59 used as patch cables• Not designed for long distances

Pin assignments from EIA/TIA-568-B standard • Eight conductor 100-ohm balanced twisted-pair cabling T568A and T568B are different pin assignments for 8P8C connectors • Assigns the T568A pin-out to horizontal cabling Many organizations traditionally use 568B • Difficult to change in mid-stream You can't terminate one side of the cable with 568A and the other with 568B • You'll run into problems

Transmission by light • The visible spectrum No RF signal • Very difficult to monitor or tap Signal slow to degrade • transmission over long distances Immune to radio interference - There's no RF

DB-15 connector • More accurately called DE-15 Blue color • PC System Design Guide Analog signal • No digital • Image degrades after 5 to 10 meters

Video and audio stream • All digital, no analog • ~ 20 meter distance before losing too much signal 19-pin (Type A) connector • Proprietary connector miniHDMI • Type C connector • Designed for smaller devices

VESA standard • Video Electronics Standards Association • A royalty-free standard Data is sent in packetized form • Like Ethernet and PCI Express Compatible with HDMI and DVI • Passive adapter

Single and dual link • Single link; 3.7 Gbps (HDTV at 60 fps) • Dual-link; 7.4 Gbps (HDTV at 85 fps) DVI-A • Analog signals DVI-D • Digital signals DVI-I • Integrated • Digital and analog in the same connector

Digital signals

Analog signals

Integrated Digital and analog in the same connector

Integrated Digital and analog in the same connector

High-speed serial connector • Data and power on the same cable • Based on Mini DisplayPort (MDP) standard Thunderbolt v1 • Two channels • 10 Gbit/s per channel • 20 Gbit/s total throughput • Mini DisplayPort connector Thunderbolt v2 • 20 Gbit/s aggregated channels • Mini DisplayPort connector Thunderbolt v3 • 40 Gbit/s aggregated throughput • USB-C connector Maximum 3 meters (copper) • 60 meters (optical), daisy-chain up to 6 devices

Simplify connections • Printers, storage devices, keyboard, mouse

Low speed: 1.5 megabits per second, 3 meters Full speed: 12 megabits per second, 5 meters USB 1.0/2.0 Standard-A Plug

480 megabits per second, 5 meters USB 1.0/2.0 Standard-B Plug

SuperSpeed 5 gigabits per second, ~3 meters Standard does not specify a cable length

USB 3.1 • Released July 2013 • SuperSpeed+ • 10 Gbit/sec USB 3.2 • Released September 2017 • SuperSpeed+ over a USB-C connector • 10 Gbit/sec and 20 Gbit/sec

USB has a lot of different connectors • And they have changed over time Can be annoying to connect USB-A • Third time's a charm USB-C replaces all of these • One connector to rule them all USB-C isn't necessarily USB 3.1 • The cable must support the function • USB 3.1 speeds • Power delivery (> 7.5 watts) • Alternate mode (additional data wires)

D-subminiature or D-sub •Different sizes, A through E Commonly used for RS-232 • Recommended Standard 232 • An industry standard since 1969 Serial communications standard • Built for modem communication • Used for modems, printers, mice, networking Commonly used as a configuration port • Serial console interface

This cable has seven conductors, one keyed connector for the drive, and one keyed connector for the drive controller.

a 15-pin flat power connector that provides power to SATA drives.

Parallel AT Attachment • Remember the PC/AT? An evolutionary process • Circa 1999 Originally called Integrated Drive Electronics (IDE) • A Western Digital invention • 2nd generation called EIDE (Enhanced IDE) The evolution • Promised faster speeds • From 16 MB/s through 133 MB/s • Additional devices Now called Parallel ATA (PATA)

40 or 80 pins

Small Computer Systems Interface • Not really "small" any longer Originally designed to string many peripherals together onto a single cable/controller • Up to 16 devices in a SCSI "chain" Many different formats • Fast SCSI, Ultra SCSI, Ultra Wide SCSI, Ultra2 SCSI • Ultra3 SCSI, Ultra-320 SCSI, Ultra-640 SCSI • iSCSI (SCSI over IP) Parallel and serial options

Not just for hard drives • Scanners, tape drives, CD-ROM drives Many devices on a single bus • 8 on a narrow bus, 16 on a wide bus Very intelligent interface functionality • Much of the difficult configuration work is done between the SCSI devices Industry longevity • Well supported in the enterprise • A standard drive for virtual systems

Every SCSI device on a single bus is assigned a separate ID number • SCSI ID 0 (SCSI controller), ID 2 (hard drive), ID 3 (CD-ROM) Logical units (LUNs) are defined within each SCSI ID • Separate drives in a storage array or virtual machine The signal at the "end" of a physical SCSI bus is terminated • Can be internal to the device or a separate termination device • Serial attached SCSI (SAS) devices have no jumpers, terminators, or settings.

Move from parallel to serial • Increased throughput • Similar to the move from PATA to SATA Point-to-point connection • No more daisy chains No termination required • The bus has two devices on it The control and management of SCSI • The speed of a serial connection

The best laid plans... • Need an adapter Convert between different connectors • Electrically compatible Convert from one format to another • You need Ethernet but you only have USB A good temporary fix • Or a good permanent one

DVI-D and HDMI are electrically compatible • HDMI is backward-compatible with DVI-D • No signal conversion required • No loss of video quality

video graphics array is a standard analog video port for connecting to an analog video display

(Phone jacks)

The devices in an Ethernet are connected with network cables terminated at each with a plastic this.

A type of connector commonly used in television production. the female and male versions lock together securely with a simple 1/4 turn.

Computer power connectors used by optical drives, hard drives, and case fans. Keyed to prevent it from being inserted into a power port improperly.

Fixed Connectors -Connected to power supply, may have too many connectors, may have not enough Modular Connectors -Add cables as needed -Fewer leftover wires, better airflow -More expensive

Random Access Memory (RAM) is the most common • But it's not the only kind of memory RAM is not referring to hard drive or SSD storage • Don't mix the two terms Data is stored permanently on the drive • Data and programs can only be used when moved to RAM

Memory types have changed through the years • Driven by standardization and technology One of the most important components of your computer • Speed, speed, speed Every motherboard is different • Check your documentation

Electrical contacts are different on each side 64 bit data width

The memory on the DIMM Dynamic - Needs constant refreshing • Without refreshing, the data disappears Random access • Any storage location can be accessed directly • Unlike magnetic tape

Synchronous DRAM (SDRAM) SDRAM is synchronous with the common system clock • Queue up one process while waiting for another • Classic DRAM didn't wait for a clock signal

Faster speeds • Twice as fast as DDR Not backwards compatible • DDR2 won't work in DDR slots

Twice the data rate of DDR2 • Larger chip capacities - Maximum 16 GB per DIMM No backward compatibility • Speed brings sacrifice

Speed increases over DDR3 • Faster frequencies • Maximum 64 GB per DIMM • Again, no backwards compatibility

Dual-channel, triple-channel, or quad-channel Memory combinations should match • Exact matches are best Memory module slots are often colored differently

Used on critical computer systems • VM servers, database servers, any server Parity memory • Adds an additional parity bit • Won't always detect an error • Can't correct an error Error Correcting Code (ECC) • Detects errors and corrects on the fly • Not all systems use ECC • It looks the same as non-ECC memory

Small bumps read with a laser beam • Microscopic binary storage CD-ROM (Compact Disc ROM) • 700 megabytes (MB) capacity DVD-ROM (Digital Versatile Disc) • 4.7 gigabytes (GB) for single-layer • 8.5 GB for dual-layer Blu-ray Disc • 25 GB for single-layer, 50 GB for dual-layer

M.2 doesn't guarantee NVMe • Your M.2 interface may be using AHCI • Check your documentation Your motherboard may only support one type of M.2 key

"Burners" don't create bumps • They darken photosensitive dye Compact Disc-ReWritable (CD-RW) DVD Read and Rewritable (DVD-R/RW) • And Dual Layer (DVD-R DL) Blu-ray Disc Recordable (BD-R) Blu-ray Disc Recordable Erasable (BD-RE)

Non-volatile memory • No moving parts - Very fast

SATA was designed for hard drives • Uses AHCI (Advanced Host Controller Interface) to move drive data to RAM • SATA revision 3 throughput up to 600 MB/s • SSDs need a faster communication method NVMe (Non-volatile Memory Express) • Designed for SSD speeds • Lower latency, supports higher throughputs • Take advantage of NVMe with an M.2 interface

Smaller storage device • No SATA data or power cables Can use a PCI Express bus connection • 4 GByte/second throughput or faster Different connector types • Needs to be compatible with the slot key/spacer • B key, M key, or B and M key • Some M.2 drives will support both

Non-volatile magnetic storage - rapidly rotating platters Random-access • Retrieve data from any part of the drive at any time Moving parts • Spinning platters, moving actuator arm • Mechanical components limit the access speed • Mechanical components can also break

Solid State Hybrid Drive (SSHD) • Both a spinning drive and SSD in a single device SSD caches the slower spinning hard drive data • Increases speed without the cost of an SSD-only system Looks like a normal hard drive or SSD - Same form factor

Flash memory • EEPROM (Electrically erasable programmable read-only memory) • Non-volatile memory - No power required to retain data A limited number of writes - Can still read the data Not designed for archival storage - Easy to lose or damage

Redundant Array of Independent Disks • They're also inexpensive disks Different RAID levels • Some redundant, some not RAID 0 - Striping RAID 1 - Mirroring RAID 5 - Striping with Parity Nested RAID - RAID 1+0 (a.k.a. RAID 10) • A stripe of mirrors

Software-based RAID • A feature of the operating system • Doesn't require any special hardware • Usually lower-performance than hardware-based Hardware-based RAID • A feature of the hard drive controller • Configured outside of the OS • Usually invisible to the operating system • High performance, designed for speeds

Add and remove while the system is running • The connection is "hot" Drive chassis • Two or more drives Easy to repair • Replace a drive while the system is running • Combine with RAID for 100% uptime

File blocks are split between two or more physical drives High performance • Data written quickly No redundancy • A drive failure breaks the array • Raid 0 is zero redundancy

File blocks are duplicated between two or more physical drives High disk utilization • Every file is duplicated • Required disk space is doubled High redundancy • Drive failure does not affect data availability

File blocks are striped • Along with a parity block • Requires at least three disks Efficient use of disk space • Files aren't duplicated, but space is still used for parity High redundancy • Data is available after a drive failure • Parity calculation may affect performance

The speed of striping, the redundancy of mirroring • The best of both worlds Need at least 4 drives

Physical size - case sizing Basic layout - room for small changes Power - standard connectors Airflow - increasingly important Wikipedia: There are 40 different motherboard types categorized!

Advanced Technology Extended Standardized by Intel in 1995 • Seen many updates over the years Power • 20 pin connector • 24 pin connector, additional 4/8 pin connector ATX motherboards are still manufactured in 2019

Smaller than an ATX motherboard • Limited expansion slots Backward compatibility • Similar mounting points • Similar power Very popular form factor • Actively manufactured as of 2019

A series of low-power motherboards • Developed by VIA Technologies in 2001 Mini-ITX is screw-compatible with ATX and microATX • Fits almost any enclosure Small form factor uses • Single-purpose computing, i.e., streaming media

Communication path • A city of technology Internal PC growth • Independent pathways System expansion • Additional capabilities

"Width" in bits • Big roads, little roads • Width is changing to bandwidth Clock speed of the bus • The expansion bus gets its own clock • 1 MHz (megahertz) = 1 million cycles per second • 1 GHz = 1000 MHz = 1 billion cycles per second Clock speed does not necessarily equal transfer rate • DDR3 SDRAM can transfer 64 times the memory clock speed

Peripheral Component Interconnect • Nobody ever calls it that • Created in 1994 A common expansion interface • 32-bit and 64-bit bus width • Parallel communication Throughput varies by bus version • 133 MB/s (32-bit at 33 MHz) • 266 MB/s (32-bit at 66 MHz or 64-bit at 33 MHz) • 533 MB/s (64-bit at 66 MHz)

Also known as PCIe • Replaced PCI, PCI-X, and AGP (Accelerated Graphics Port) Communicates serially • Unidirectional serial "lanes" • Slower devices don't slow down everyone One, two, four, eight, sixteen, or thirty-two full-duplex lanes • x1, x2, x4, x8, x16, x32 • "x" is pronounced "by" i.e., "by 4," "by 16"

Different versions of PCIe • Improvement in speed with each iteration Per-lane throughput in each direction • v1.x: 250 MB/s • v2.x: 500 MB/s • v3.0: ~ 1 GB/s • v4.0: ~ 2 GB/s • v5.0 (expected in 2019): ~ 4 GB/s

Motherboards are matched with CPUs • CPUs have specific socket requirements CPU socket is usually the largest thing on the board • And usually central to everything Not easily upgradable - and often not an option

Reverse the PGA - pins are on the motherboard No pin to damage on the CPU • Easier to damage the motherboard

Various front-panel connections • Not directly connected to the motherboard

USB on the motherboard Integrated - part of the motherboard • On the back - keyboard, mouse Internal case connection • Pins for case interfaces

The software used to start your computer • The firmware • System BIOS, ROM BIOS • ROM or flash memory Initializes CPU and memory • Build the workspace POST - Power-On Self-Test Look for a boot loader - Start the operating system

The original / traditional BIOS • It's been around for more than 25 years Older operating systems talked to hardware through the BIOS • Instead of accessing hardware directly Limited hardware support • No drivers for modern network, video, and storage devices

Unified Extensible Firmware Interface • Based on Intel's EFI • (Extensible Firmware Interface) A defined standard • Implemented by the manufacturers Designed to replace the legacy BIOS • Need a modern BIOS for modern computers • Graphical and text-based

Boot from large (> 2.2 TB) GUID partition table (GPT) disks • Also supports FAT and removable media Includes a pre-boot environment • This isn't an operating system • Has its own shell, drivers, and applications • Browse the Internet, backup a storage drive • Remote diagnostics, even without an OS

Store the BIOS configuration • Your settings Complementary metal-oxide semiconductor (CMOS) • A type of memory • May be backed up with a battery Usually flash memory these days • Easily stored and accessed

Not needed for today's flash-based storage • Maintains older BIOS configurations • May only be used to maintain date/time A bad battery will require a BIOS configuration or date/time configuration on every boot On older systems, can reset the BIOS configuration by removing the battery • Newer computers use a jumper

Launching the system setup • Del, F1, F2, Ctrl-S, Ctrl-Alt-S Microsoft Virtual PC (Windows 7) • https://support.microsoft.com/en-us/kb/958559 Hyper-V (Windows 8/10) • Turn Windows features on and off VMware Workstation Player • http://www.vmware.com/products/player/ But not VirtualBox • http://www.virtualbox.org

Windows 8 and Windows 10 • Doesn't actually shut down all the way • Starts up very quickly Starts up so quickly, you can't open the BIOS configuration • This can be an issue Disable fast startup in Control Panel / Power Options • If you can Most motherboards have a separate process • Hold F2, then press the power button, for example

RAM - View and configure memory settings Hard drive / SSD • Drive settings • Boot order Optical drive• Enable / Disable • CPU - CPU types

Part of the BIOS • Always available • Run from the BIOS menu • No additional media or software required Focused on hardware checks • Doesn't touch the operating system

Have a backup of your BIOS configuration • Make notes or take a picture Don't make a change unless you're certain of the setting • It's difficult to leave it alone Did I mention the backup? • It can save a lot of time!

BIOS Password / User Password • System won't start • Need the password to start the operating system Supervisor Password • Restrict BIOS changes • Must use supervisor password to change any BIOS configurations

Everything is encrypted • Not just individual files Windows BitLocker disk encryption • BIOS integrates with TPM TPM - Trusted Platform Module • Can be added to many motherboards • Built-in to some systems • Adds advanced cryptographic functions

Originally called CompuTrace • Name licensed from the vehicle recovery service Built into the BIOS - software installed into the OS • Reinstalls itself if removed or new storage drive installed "Phone home" function - provides location information Theft mode`- remotely lock the laptop and/or delete files • Forces a startup password

Malicious software can "own" your system • Malicious drivers or OS software Secure boot - part of the UEFI specification Digitally sign known-good software • Cryptographically secure • Software won't run without the proper signature Support in many different operating systems • Windows and Linux support

Firmware • Non-volatile memory and software • Older-style ROMs • Newer-style flash memory Computer BIOS, video adapter firmware, game console, etc. • Improve performance, fix bugs Not usually part of a normal maintenance process • Upgrade for a specific reason

May appear when system starts • Can be difficult to catch Easier to look in System Information (msinfo32) • Version and date details Compare the current to the existing • An upgrade may not be available If possible, get a copy of the current version • Always good to have a backup plan

Read the documentation • Some BIOS updates are bland • Others are full of new features • Check for OS prerequisites Locate a reliable power source • Laptop: Connect to AC power and have a full battery • Desktop: Use a UPS, if possible

Really-old BIOS upgrades may require a boot disk • Floppy or optical media Most modern upgrades run as an executable • Close all of your other applications before running • May also run in the BIOS from a flash drive Most upgrade apps will check for prerequisites • Don't rely on this Requires a reboot • Save your documents!

Newer options may be available • Modern motherboards have advantages Multiple BIOS versions • Two separate BIOS versions • Easily switch between them Upgrade from a USB flash drive • Computer may not even need to be powered on

Dual-core / Quad-core / Octa-core / Multi-core • And more all the time Multiple cores • Each core has its own cache • The entire chip may have a shared cache

Super fast memory • There's not much of it • Holds data, instructions, and/or results Level 1 cache • First check Level 2 cache • Secondary data Level 3 cache • Still on the chip • These days

Run other operating systems within a single hardware platform • Multiple operating systems share physical hardware components Virtualization in software was limited • Performance and hardware management challenges Virtualization added to the processor • Hardware is faster and easier to manage • Intel Virtualization Technology (VT) • AMD Virtualization (AMD-V)

Hyper-Threading Technology (HTT) One CPU, acts like two Doesn't actually work as fast as two • 15% to 30% performance improvement Operating system must be written for HTT • Windows XP and later (any modern OS)

Real speed: CPU clock • Historical qualification of speed • Megahertz (MHz) or gigahertz (GHz) Actual speed • Combination of different factors • Clock speed, CPU architecture, bus speed, bus width, • L1 cache size, L2 cache size, operating system capabilities CPU manufacturers have moved away from marketing performance in clock cycles No broadly accepted measure of performance • Use a benchmark that works for you

When fast isn't fast enough • Increase the clock speed past the rated value A balancing act • More power required, more heat created • At some point, the system becomes unstable Change the base clock (BCLK) - Need an unlocked CPU • Run a stress test to confirm the stability This will void your warranty • You can break more than your CPU

Graphics processing unit • Part of a video adapter, motherboard, or CPU Graphics rendering requires a lot of work • Dedicated hardware speeds the process On-die GPUs are increasingly common • But not as powerful as separate adapters

Two solid CPU manufacturers - The differences are subtle Cost - AMD tends to be a bit less expensive Laptops • Intel has a large portfolio of options Choosing a side • Historically, AMD is value and Intel is performance • This is a dynamic technology segment

Cool air is pulled through a personal computer • Always check for good airflow Motherboard layout becomes important Component location is key • Devices, wiring, power Many different sizes and styles • And volume levels

Designed to cool an entire adapter card • Can be bulky • May take additional adapter card space • Usually seen on high-end graphics cards

Fan specifications Standard sizes i.e., 80 mm, 120 mm, 200 mm Different speeds • Variable speed Different noise levels • Not all fans sound the same

Dissipate heat through thermal conduction • Copper or aluminum alloy Fins/grid increase surface area • Heat is then transferred to the cooler air Thermal paste creates a good contact between the chip and the heat sink They get HOT - don't touch them!

No fans, no noise • Silent operation Specialized functions • Video servers, TV set top box, satellite receiver, media server Functions are very controlled • Carefully measured thermal tests Low-power components • Heat sinks

Coolant is circulated through a computer • Not a new concept • Automobiles, mainframe computers High-end systems Gaming, graphics Overclocking

Extend the functionality of your computer • You may need more than the motherboard provides Relatively simple process • Designed for end-user installation Install hardware • Add a card Install a driver • Software for the operating system

Check the motherboard documentation • Number and type of slots Check the adapter card documentation • Minimum requirements - Hardware, software Knowledge base • Any "gotchas?" Support forums • What are other people saying? You may need to perform a driver installation before installing hardware

• You checked the documentation first, right? • Check the web for the latest version • Uninstall previous drivers through Windows Device Manager • Manufacturer-provided setup program • Manual installation through • Windows Device Manager • Check the Device Manager for the status • Does it work

Color and B&W output • Paper documents, photos All-in-one - AIO • Printer, scanner, copier, fax Connectivity • USB • Ethernet • 802.11 Wireless • Bluetooth / Infrared

Connected via USB or 802.11 wireless Different form factors • All-in-one • Flatbed May include an ADF • Automatic Document Feeder

Serial or USB connector • Or 802.11 wireless Or with your phone • Built-in camera

The human's display device • The most popular output device Many different connections • Different standards through the years Many different standards • And sizes • And resolutions

Virtual reality • Headset determines what you see Motion tracking • X, Y, and Z axis Interact with a virtual environment • Gaming • Education • Art • Travel

Store and read data with light • Uses a laser to read and write Read/write media • Store backups and documents Read-only media • Data can't be deleted • Common for video distribution Limited storage sizes • Dual-layer Blu-ray holds 50 GB

USB connection • Or an adapter for PS/2 Optical mice have few moving parts • May need the right surface • Glass may cause a problem

Connected via USB • Or an adapter for PS/2 Additional features may require additional drivers and/or software

Integrated into the keyboard • Maybe a standalone device • Connected via USB or Bluetooth Replaces a mouse • Uses no additional space

We've gone paperless • But we still need somewhere to sign Small digitizer • And stylus USB connection • Driver may be required

Game pad and Joystick • USB connected • Used almost exclusively for games

Video capture • Built-in camera • USB connected • 802.11 Wireless Usually includes both audio and video • Specialized drivers and software

Integrated into most new laptops and multimedia devices • Also external Connectivity • Analog - TRS (Tip / Ring / Sleeve) • Digital - USB

Analog output devices • Compatible with our ears Connectivity • TRS (Tip / Ring / Sleeve) jacks • Speaker output, audio adapter

Headphones and microphone • One unit Desk and mobile use • USB • TRS plug • Wireless / Bluetooth Talk and listen • Desktop telephone • Mobile communication • Gaming

Not always LCD • But common to see LCD • Metal-halide lamp • Very bright (very hot) light • Brightness measured in lumens • Relatively expensive • (~ $35 to $350+ US) • Always let bulbs cool • Fan will run after shutting off • Keep it plugged in

Storage outside the computer, and often removable • Very portable, easy to move large files • USB flash drive, SSD, hard drive • Many different connectivity options • USB, Thunderbolt, eSATA, etc • Very large storage options • And very mobile • Can be a security concern

Keyboard, Video, and Mouse • Use many computers with a single keyboard, video display, and mouse

Point of sale terminal • Method of payment • Credit card Support for different formats • Integrated circuit • Physically inserted into reader • Magnetic strip • Backward compatibility Reader is USB connected • To a point of sale (POS) terminal

Near-field communication • ~10 centimeter wireless range Built into many phones • Integrates with a payment terminal Many different uses • Contactless payment systems • Identity token / door key • Gaming and entertainment

Smart card • Card with embedded circuitry Used in payment cards, identification cards Useful form of authentication • Username, password, physical smart card Readers are built-in or external - USB connected

Always disconnect from the power source when working on a device • Always. Seriously Some devices store a charge in capacitors • Know how to discharge before touching Never connect your body to any part of an electrical system • Do not connect yourself to an electrical ground Respect electricity - It does not respect you

Computer uses DC voltage • Most power sources provide AC voltage Convert 115 V AC or 220 V AC • To 3.3V DC, 5 V DC, and 12 V DC • You'll know when this isn't working

Ampere (amp, A) - The rate of electron flow past a point in one second • The diameter of the hose Voltage (volt, V) • Electrical "pressure" pushing the electrons • How open the faucet is

Watt (W) • Measurement of real power use • volts * amps = watts • 120V * 0.5A = 60W

Alternating current (AC) -curve line • Direction of current constantly reverses • Distributes electricity efficiently over long distances • Frequency of this cycle is important • US/Canada - 110 to 120 volts of AC (VAC), 60 hertz (Hz) • Europe - 220-240 VAC, 50 Hz Direct current (DC) straight and break lines • Current moves in one direction with a constant voltage

Voltage varies by country • US/Canada - 110 to 120 volts of AC (VAC), 60 hertz (Hz) • Europe - 220-240VAC, 50 Hz Manually switch between 110 V/115 V and 220 V/230 V • Get your meter! Or use an auto-switching power supply Don't plug a 115 V power supply into a 230 V power source!

Main motherboard power • Provides +3.3 V, +/-5 V, and +/- 12 V 20 pin connector was the original ATX standard • 24 pin was added for PCI Express power • You can connect a 24-pin connector to a 20-pin motherboard • Some cables are 20-pin + 4-pin

Different voltages - For different components Positive and negative voltage • Voltage is a difference in potential • The electrical ground is a common reference point • Depends on where you measure from At the front door of your house • The second floor is +10 feet • The basement is -10 feet +12 V • PCIe adapters, hard drive motors, cooling fans, most modern components +5 V • Some motherboard components • Many components are now using +3.3 V +3.3 V • M.2 slots, RAM slots, motherboard logic circuits -12 V • Integrated LAN • Older serial ports • Some PCI cards -5 V • Available for ISA adapter cards • Most cards didn't use it • Today's motherboards don't have ISA slots

Power supplies are rated by watts • Overall and by individual voltages Bigger isn't necessarily better • More expensive • Doesn't speed up your computer Physical size is relatively standard • Older cases and systems may have proprietary sizes Calculate the watts required for all components • CPU, storage devices, video adapter • Many online calculators Video adapters are usually the largest power draw • Many video card specifications list a recommended power supply wattage 50% capacity is a good rule of thumb • Power supply runs efficiently and there's room to grow

Computer Aided Design (CAD) / • Computer Aided Manufacturing (CAM) SSD • High-speed storage High-end video • Complex graphics Maximum RAM • Significant memory use

specialized audio and video card • High quality audio • Powerful video Large fast hard drive • Constant disk writes • SSD Dual monitors • Edit in one monitor, view output in the othe

Maximum RAM • Every OS needs its own memory • It adds up quickly! Maximum CPU cores • Constant processing • Need an efficient CPU • Most virtualization apps can use multiple cores

SSD • Fast start and load times • High-end video/specialized GPU • Graphically complex • High definition sound card • Multiple layers, atmosphere • High-end cooling • High utilization for hours at a time

Desktop applications • Executable programs running in local memory and using local CPU • Meets recommended requirements for running the operating system • CPU, total RAM, disk space

Basic application usage • Applications actually run on a remote server • Virtual Desktop Infrastructure (VDI) • Local device is a keyboard, mouse, and screen • Minimal operating system on the client • No huge memory or CPU needs • Network connectivity • Big network requirement • Everything happens across the wire

NAS - Access from anywhere • Media streaming - Central location • File sharing - Easy access • Gigabit NIC - High speed transfers • RAID array - Redundant hard drives

Very little client configuration • All the work is done on the server • Mouse, keyboard, network, monitor • And power on • Minimal OS on the client • Most of the OS is on the server • Apps are centralized on the server • Few moving parts, if any • Inexpensive to buy • Easy to replace

A traditional computer • With all of the requirements Local resources • Operating system • Device drivers • Applications Ongoing support • Security patches • Operating system updates • Application updates

Centralized account management • Microsoft Active Directory • User account added to the directory Thin client - No local permissions required Thick client • Device is added to the Microsoft domain • User authenticates to gain access to the thick client

A thick client that moves • Mobility brings additional administrative concerns • Touchpad configuration - Finger combinations and swiping • Synchronization and backup - Cloud-based or local drive • Wireless connections - Mobility in the office and elsewhere • Additional security - VPN connectivity, local drive encryption

Centralized management - Mobile Device Manager (MDM) • Touchscreen configuration - Lock codes and biometric access • Application installations - Set by policy and requirement • Synchronization and backup - Cloud-based • Wireless enabled - Includes VPN connectivity

SOHO • Small-office / Home-office Multifunction devices • Printer • Scanner • Fax (yes, really) • Network connection • Phone line connection • Print from web There are a lot of things that can go wrong • You're going to fix them

Specific to a printer model • Get this exactly right • Get the right operating system drivers • Windows 7, Windows 8/8.1, Windows 10 • Get the right version of the operating system • 32-bit drivers are very different from 64-bit drivers • You can't mix and match drivers • It's a very specific task

Duplex • Printing on both sides of the page without manually flipping over the paper • Not all printers can do this Collate • Print multiple copies in their proper order • Non-collated: • Page 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4 Collated: • Page 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4 • Very useful for many copies of large documents Orientation • Portrait vs. Landscape • The paper doesn't rotate • The printer compensates Quality • Resolution • Color, greyscale • Color saving

USB type B • The most common connector • USB Type B on the printer, • USB Type A on the computer Parallel • Legacy systems • Centronics interface on the printer • DB-25 on the computer Ethernet • RJ45 connector

Connector used with older printers.

Bluetooth • Limited range 802.11 a/b/g/n/ac Infrastructure mode • Many devices using an access point 802.11 Ad hoc mode • No access point • Direct link between wireless devices

Integrated print server • Print directly to the printer • Jobs are queued on the printer • Jobs are managed on the printer • Web-based front-end • Client utility Cloud printing • Print to the cloud • Useful from mobile devices • The cloud sends to your printer • Google, Brother, HP, etc

Network ports • Common on Windows devices • Commonly uses tcp/139, tcp/445, udp/137, and udp/138 Bonjour • Discover Apple devices on the LAN • Part of macOS • Can be added to Windows (iTunes, etc.) AirPrint • Print from iOS devices to compatible printers

User authentication • Everyone can print • Set rights and permissions • Printing vs. managing the printer Print and scan caching • Click print • Local system creates a file of the output • Output file is sent to the print server spooler • Printing is done from the spool file • Spool file is deleted when done (but not always)

Combine a laser, high voltage, charged ions, powdered ink, heat, and paper • Very high quality • Fast printing speeds • Very complex, many moving parts, requires on-printer memory and messy on the inside

Image is drawn onto a photosensitive drum • "Painted" with a laser Picks up toner - Transfers toner to the paper Can be separate from the toner cartridge or combined Step 1: Processing • Build the entire page in memory Step 2: Charging • Prepare the drum with a negative electrostatic charge Step 3: Exposing • Write the image with the laser Step 4: Developing • Add toner to the charged areas of the imaging drum Step 5: Transferring • Move the toner from the drum to the paper Step 6: Fusing • Heat and pressure Step 7: Cleaning • Remove excess toner

Heat and pressure - Melt plastic toner powder • Permanently bond toner to paper

Color laser printers • Cyan, yellow, magenta, black Four separate toner cartridges Image is transferred from all cartridges to the single belt • And then to a single transfer roller

Printers usually print on a single side • Not both sides simultaneously Printing on both sides is a two step process • Print side one, print side two You need mechanisms to "flip" the page • Automatically Can be built-in to the printer • Or available as an add-on

Look for the messages • Low doesn't mean empty The toner can also contain the OPC drum • Organic Photoconductor drum • Sensitive to light; keep it in the bag Power down the printer • Safety first Remove packing strips from the new drum • Replace it with the old

Laser printers wear out • All those moving parts • Heat and pressure Standard maintenance kits • Replacement feed rollers, new fuser unit, etc. When to perform maintenance? • Check the printer's page counter Power down and replace the components • Fuser units are HOT Reset the page counter when you're done!

Different toner cartridges print with different densities • Some dark, some light Laser printer calibration can adjust the density • Makes it looks perfect Can be automated or a manual process • Every printer is different • Check the printer manual

Laser printers are dirty - All that toner and paper dust Check the manufacturer's recommendations • Water, isopropyl alcohol (IPA) • Don't use harsh chemicals! Outside - Damp cloth Inside - Wipe the dust away • Don't use a normal vacuum cleaner or compressed air • Wash off skin with cold water • Clean rollers with IPA

Relatively inexpensive technology Quiet High-resolution Expensive ink • Proprietary Eventually fades Clogs easily

Some consumer printers integrate the print head into the ink cartridge • Change the cartridge, get a new print head Others separate the ink cartridge from the print head

Pick up and feed paper through the printer • Must be clean and not worn Duplexing • Print on both sides of the paper • Included with some printers

Ink cartridges are moved over the paper • Carriage may include its own print head Belt moves the carriage back and forth • Another moving part

Align nozzles to the paper • Lines should be crisp • Colors should align Printer includes a calibration option • May need to make minor adjustments

Small droplets of ink • And small holes in a print head Clogged heads is a big issue • Many printers automatically clean every day • Output has streaks or sections of missing color Cleaning process can be started manually • Only takes a few minutes Some print heads/cartridges can be removed • Manually cleaning may help

Usually separate colors • Cyan, Magenta, Yellow, and Key (CMYK) • Some cartridges will combine these Takes seconds to replace • Takes a few minutes to calibrate and prepare the cartridge Recycle the empty cartridge • All plastic

Lots of turns and twists • A jam is inevitable Remove tray paper • Any loose paper Remove paper from the path • Firm pressure, don't rip Check for any scraps of paper •Remove all loose paper

White paper • Turns black when heated • No ink! VERY quiet • Almost silent Paper is sensitive to light and heat • And clear tape

Pull paper through the printer • Relatively small paper path

Full-length heating element • No moving print head

Paper-covered with a chemical • Changes color when heated Cash registers, credit card terminals • And quiet areas Looks like normal paper • Feels a bit different

Relatively inexpensive • But impossible to substitute Different sizes • Not like laser printer paper • Keep a list Actual replacement process is easy • Simple paper feed • Small device

Swab gently • Usually small areas Use a cleaning card • Cleans the head • And paper pathways

Relatively small amount • Paper bits and dust • No toner! Blow out the printer • Take it outside Wipe it out • Damp cloth Avoid using a vacuum • Unless it's designed for computers • Resists static buildup/discharge

Print head with a small matrix of pins • Presses against a ribbon to make a mark on paper Good for carbon/multiple copies Low cost per page NOISY Poor graphics Niche use - Car rental, airports

Liquid cleaner • Isopropyl alcohol (IPA) • Get a cleaning pen • Check manufacturer's recommendations

Fabric • One long ribbon - Never ending circle Easy to replace - Once single unit Proprietary size - Specific to printer model

Paper pulled through with holes on the side of the paper • Instead of using friction Continuous paper feed • Perforations between pages Holes have to line up perfectly • Tractor paper can be perforated to remove holes

Single ribbon • Self-contained - One long circle Replace when ink becomes too light • Ink is eventually consumed • Designed to be modular - Replace in less than a minute

Takes a lot of abuse • Directly hits the ribbon and paper Gets hot - Watch your fingers • Another modular part - Look for a release lever or bar Replace with the ribbon for the best effect • The output should look perfect

Not as easy as a laser printer • Paper must feed perfectly into holes • Tractor feed Forms must be positioned correctly • Text needs to fit a predefined space Paper must feed without constraint • Make sure nothing is in the way

No physical output • Output to a "digital" document No additional hardware required • No printer, no paper Useful for sending electronically • Easy to manage

You need to print to a printer at work • You're at home Print to the work printer driver • But save it as a file File will be in an output format specific to that printer • You can't open it with another program Must use the command line to copy the file to the printer, i.e., copy filename LPT1:

Adobe PDF • Portable Document Format • A one-way path from application to PDF • Cross-platform compatibility Proprietary Adobe format • Requires specialized software to create and view a PDF • PDF viewers built into many Internet browsers Many third party tools available • Some applications will print to PDF without any additional software

Microsoft XPS • XML Paper Specification Similar use case to Adobe PDF • But XPS is included in Windows • And available all the way back to Windows XP Print to XPS, view in any operating system • If there's an XPS reader

Print to a graphics image • For later image editing or sharing Not integrated into the OS • A feature of the application Some third-party image print drivers are available • Application may export graphics formats natively

"Print" in three dimensions • Create a 3D item based on an electronic model Additive manufacturing • Melt plastic filament in layers to create the object • No machining process required Rapid prototyping • Design and create relatively quickly and inexpensively Deploy designs anywhere in the world • Or into space

Sometimes called Hardware as a Service (HaaS) • Outsource your equipment • You're still responsible for the management and security • Your data is out there, but more within your control • Web server providers

On-demand software - No local installation • Why manage your own email distribution or payroll? Central management of data and applications • Your data is out there A complete application offering • No development work required, i.e., Google Mail

No servers, no software, no maintenance team, no HVAC • Someone else handles the platform, you handle the development You don't have direct control of the data, people, or infrastructure • Trained security professionals are watching your stuff Put the building blocks together • Develop your app from what's available on the platform • SalesForce.com

Private - Your own virtualized local data center Public - Available to everyone over the Internet Hybrid - A mix of public and private Community Several organizations share the same resources

On-premises • Your applications are on local hardware • Your servers are in your data center in your building Hosted • Your servers are not in your building • They may not even be running on your hardware • Usually a specialized computing environment Cloud • Entire application instances can be created and torn down on-demand • Resources are available as needed

Internal cloud • No resources are shared • Build your own cloud • Pay for everything up front • No ongoing costs External cloud • Share resources with a public cloud • Underlying infrastructure owned by a third-party • Cost may be metered or up-front

Rapid elasticity • Scale up and scale down as needed • Seamless to everyone On-demand self-service • Adding software, networks, servers, storage is a challenge outside the cloud • The cloud enables instant resource provisioning Resource pooling • All of the computing power in one place • One large resource instead of many small resources Measured service • Costs and utilization are very closely tracked • Resource planning and granular chargebacks

Metered cloud services • You pay for what you use • Cost to upload • Cost to store • Cost to download Non-metered • You pay for a block of storage • No cost to upload • No cost to download

Email is a staple • Detailed electronic communication A challenge to maintain • Expensive hardware and storage • Trained support team • Ongoing backup and maintenance Cloud-based email hosting • Flat cost per user per month • Personal options may have no direct cost • Looks and feels the same for the user Microsoft Office 365, Google Mail

Store your files in the cloud • Access, share, and edit from anywhere Easy to collaborate - One place for all files Synchronization app • Store files on a local drive • The app synchronizes to the cloud • Sync files to other devices Cloud storage providers • Dropbox, Google Drive, Box, Microsoft OneDrive

On-demand applications • No local installation • Globally distributed User starts the application • The components are downloaded as needed • If you don't use a component, you don't download it • User data is stored securely in the cloud Easy to update • The application is in one place • Some data is cached, only update the changes

Mobile phones / tablets • Run an app (or portion of an app) in real-time • Try many different apps or components • Can be cached locally for later use Applications for laptop/desktops • No complex deployment process • Apps are only streamed if they are used • New applications are simply added to the cloud offering • Quickly manage and make changes

A virtual desktop infrastructure (VDI) in the cloud • Users connect to a pre-built desktop Access from almost any OS • Windows, Mac OS, Linux, • iOS, Chromebook, web browser Virtual NIC • All communication in the desktop are local to the virtual desktop • No sensitive information sent from the local device

One computer, many operating systems • Mac OS X, Windows 7, Linux Ubuntu, all at the same time! Separate OS, independent CPU, memory, network, etc • But really one computer Host-based virtualization • Your normal desktop plus others Standalone server that hosts virtual machines • Enterprise-level Been around since 1967 • IBM mainframe virtualization

Virtual Machine Manager • Manages the virtual platform and guest operating systems May require a CPU that supports virtualization • Can improve performance Hardware management • CPU • Networking • Security

CPU Processor Support • Intel: Virtualization Technology (VT) • AMD: AMD-V Memory • Above and beyond host OS requirements Disk space • Each guest OS has it's own image Network • Configurable on each guest OS (standalone, NAT, bridged, etc.) • Virtual switch

Virtualization is a native operating system • Performing native OS processes • This is identical to using a non-virtual system Emulation is one device running processes designed for a completely different architecture • One device is pretending to be another • Original code is used • Code is interpreted for running on the current hardware • This is commonly slower than running natively • Emulation is not easy to do

Hypervisor is a sweet spot for the bad guys • No significant vulnerabilities yet VM escaping • Malware recognizes it's on a virtual machine • Malware compromises the hypervisor • Malware jumps from one guest OS to another Many hosted services are virtual environments • Malware on one customer's server can gather information from another

Every guest is self-contained - Like a real computer Use traditional security controls • Host-based firewall - Anti-virus, anti-spyware Watch out for rogue virtual machines (VMs) • The bad guys try to install their own system • You're in big trouble Self-contained VMs provided by • 3rd parties can be dangerous • You have no idea what's running on there

Most client-side virtual machine managers have their own virtual (internal) networks Shared network address • The virtual machine shares the same IP address as the physical host • Uses a private IP address internally • Uses NAT to convert to the physical host IP Bridged network address • The VM is a device on the physical network Private address • The VM does not communicate outside of the virtual network

Uh oh. It's broken! Identify the Problem Establish a Theory Test the Theory Not fixed yet! Evaluate Results: Is it working? Yes! Establish a Plan of Action Implement the Plan Verify Full System Functionality Document Findings It works! Yay!

Change control • A formal process for managing change • Avoid downtime, confusion, and mistakes • Corporate policy and procedures Nothing changes without the process • Plan for a change • Estimate the risk associated with the change • Have a recovery plan if the change doesn't work • Test before making the change • Document all of this and get approval • Make the change

Information gathering • Get as many details as possible • Duplicate the issue, if possible Identify symptoms - May be more than a single symptom Question users - Your best source of details Determine if anything has changed • Who's in the wiring closet? Approach multiple problems individually • Break problems into smaller pieces Backup everything • You're going to make some changes • You should always have a rollback plan What else has changed? • The user may not be aware • Environmental changes • Infrastructure changes There may be some clues - Check OS log files • Applications may have log information

Start with the obvious • Occam's razor applies Consider everything • Even the not-so-obvious Make a list of all possible causes • Start with the easy theories • And the least difficult to test Research the symptoms • Internal knowledgebase • Google searches

Confirm the theory • Determine next steps to resolve problem Theory didn't work? • Re-establish new theory or escalate • Call an expert The theory worked! • Make a plan...

Build the plan • Correct the issue with a minimum of impact • Some issues can't be resolved during production hours Identify potential effects • Every plan can go bad • Have a plan B • And a plan C

Fix the issue • Implement during the change control window Escalate as necessary • You may need help from a 3rd party

It's not fixed until it's really fixed • The test should be part of your plan • Have your customer confirm the fix Implement preventative measures • Let's avoid this issue in the future

Test major system components before booting the operating system • Main systems (CPU, CMOS, etc.) • Video • Memory Failures are usually noted with beeps and/or codes • BIOS versions can differ, check your documentation Don't bother memorizing the beep codes • They're all different between manufacturers • Know what to do when you hear them

No warning, black screen • May have some details in your Event Viewer Heat-related issue • High CPU or graphics, gaming • Check all fans and heat sinks • BIOS may show fan status and temperatures Failing hardware • Has anything changed? • Check Device Manager, run diagnostics Could be anything • Eliminate what's working

System completely stops • Completely. Usually not much in the event log • Similar to unexpected shutdowns Check for any activity • Hard drive, status lights, try Ctrl-Alt-Del Update drivers and software patches • Has this been done recently? Low resources • RAM, storage Hardware diagnostics may be helpful

Blank screen on boot • Bad video • Listen for beeps • BIOS configuration issue BIOS time and setting• Maintained with the motherboard battery • Replace the battery Attempts to boot to incorrect device • Set boot order in BIOS configuration • Confirm that the startup device has a valid operating system • Check for media in a startup device

How far does the boot go before rebooting? • BIOS only? OS splash screen? Bad driver or configuration • F8, "Boot from last known working configuration" Try F8, Safe Mode • If system starts, disable automatic restarts in System Properties Bad hardware • Try removing or replacing devices • Check connections and reseat

No power • No power at the source • No power from the power supply • Get out your multimeter Fans spin - no power to other devices • Where is your fan power connected? • No POST - bad motherboard? • Case fans have lower voltage requirements • Check the power supply output

Heat generation • CPUs, video adapters, memory Cooling systems • Fans and airflow • Heat sinks • Clean and clear Verify with monitoring software • Built into the BIOS • Try HWMonitor - http://www.cpuid.com/

Computers should hum • Not grind Rattling • Loose components Scraping • Hard drive issues Clicking • Fan problems Pop • Blown capacitor

Sometimes it works • Sometimes it doesn't Bad install • Check and reseat • Use all the screws Bad hardware • Poor connection • Heat and vibration

POST codes on the motherboard Power Link light Speed Activity

Electrical problems • The smoke makes everything work Always disconnect power • There should never be a burned odor Locate bad components • Even after the system has cooled down • Replace all damaged components

Windows Stop Error Blue Screen of Death - You don't want this Contains important information • Also written to event log Useful when tracking down problems • Sometimes more useful for manufacturer support

The Mac OS X Spinning Wait Cursor • Feedback that something is happening The spin starts, but it never stops • You never get back control of your computer Many possible reasons • Application bug, bad hardware, slow paging to disk Restart the computer • There may be details in the console logs

Windows • Event Viewer • Boot logs • System Configuration • C:\Windows\ntbtlog.txt Linux • Individual application logs - /var/log • Mac OS X - Utilities / Console.app

The details of an error message can make or break a troubleshooting session • Write down everything • Take a picture, make a video • Train your users The error might not make sense • Write it down anyway • The Internet will tell you what it means • Spend your time troubleshooting the right things

Read/write failure • "Cannot read from the source disk" Slow performance • Constant LED activity • Retry...retry...retry Loud clicking noise • The click of death

Get a backup • First thing - a bad drive is bad Check for loose or damaged cables Check for overheating • Especially if problems occur after startup Check power supply • Especially if new devices were added Run hard drive diagnostics • From the drive or computer manufacturer • Preferably on a known-good computer

Drive not recognized • Lights (or no lights) • Beeps • Error messages Operating system not found • The drive is there • Windows is not

Check your cables • Physical problem • Check boot sequence in BIOS Check for removable disks (especially USB) • Check for disabled storage interfaces For new installation, check hardware configuration • Data and power cables • Try different SATA interfaces Try the drive in a different computer

Missing or faulty RAID controller

Each RAID is different • Don't start pulling drives until you check the console!

Windows Stop Error, • Apple spinning wait cursor - A very serious issue May indicate a storage device issue • Diagnostics needed for drive and motherboard

Self-Monitoring, Analysis, and Reporting Technology • Use third-party utilities Avoid hardware failure • Look for warning signs Schedule disk checks • Built-in to most drive arrays Warning signs • Replace a drive

Is it connected? • We wouldn't ask if it wasn't a real solution • Check both power and signal cable Input selection on monitor • HDMI, DVI, VGA, etc. Image is dim • Check brightness controls Swap the monitor • Try the monitor on another computer No video after Windows loads • Use VGA mode (F8)

Flickering, color patterns incorrect • You can almost work with this Check the cable pins • Especially if missing a color Distorted image and geometry • Check the OS refresh rate and resolution settings • Need to match the display specifications • Native resolution is important on LCD displays • Check or replace cable Disable hardware acceleration • Troubleshoot with the software drivers Oversized images and icons • Resolution set too low • Lower = larger Burn-in • A problem across all monitor types • Some displays will pixel-shift But you won't notice it LCDs have "image sticking" • Remove by displaying a white screen for an extended period

Pixel problems • Stuck pixels (constantly bright) • Dead pixels (always black) Artifacts • Unusual graphics - check adapter • Image persistence - Turn off display • Motion trails • Disable advanced video features BSOD and Overheating • Video drivers • Monitor the internal temperature

No display or dim video • Verify the backlight • Look closely, it may be barely visible • No backlight, replace the inverters Confirm video with an external display • Video good, but LCD bad • Replace the LCD display Flickering video • Connector problem • Bad video cable • Bad video hardware

Sticking keys • Difficult to clean • Keycaps are very (very) delicate! Ghost cursor / Pointer drift • Mousepad causes cursor to bounce around • Modify the configuration to check for palm press • Update your drivers Num lock indicator lights • The letters are numbers!

Multiple antennas • WiFi main and aux, Bluetooth • Antenna wires wrap around the laptop screen Easy to accidentally disconnect during maintenance • No 802.11 wireless, no Bluetooth Check the connectors • Loose cables can cause intermittent wireless access

Battery not charging • Batteries lose capacity over time • Laptop charging hardware may be faulty No power • Check the external power adapter "brick" with a multimeter • Master laptop reset • Hold power for 10 seconds - Each laptop is different

Toggle Fn keys • Secondary functions • Toggle between LCD / external monitor / both Use external monitor • Bypass the LCD (but not the video hardware)

Touchscreen completely black or touchscreen not responding to input • Buttons and screen presses do not register Apple iOS reset • Press power button, slide to power off, press power button • Hold down power button and Home|volume for 10 seconds Android device restart • Remove battery, put back in, power on • Hold down power and volume down until restart • Some phones have different key combinations • Some phone do not have a key-based reset

Problematic apps • Apps not loading, Slow app performance Stop the app and restart • iPhone: Double-tap home button, slide app up • Android: Settings/Apps, select app, Force stop Restart the phone • Hold power button, power off Update the app • Get the latest version

Protect your email • Encrypted communication channels Built-in to corporate email systems • Microsoft Outlook Each user has a private key • You can't decrypt without the key Install individual private keys on every mobile device • Use a Mobile Device Manager (MDM)

Bad reception • Always searching for signal • Airplane mode on the ground Disable unnecessary features • 802.11 wireless, Bluetooth, GPS Check application battery usage • iPhone: Settings/Battery • Android: Settings/Battery Replace aging battery • There's only so many recharges

Phone will automatically shut down • Avoid overheating damage Charging/discharging the battery, • CPU usage, display light - creates heat Check app usage - Some apps can use a lot of CPU Avoid direct sunlight - Quickly overheats

Nothing works • No screen or button response Soft reset • Hold power down and turn off Hard reset • iOS: Hold power and home|volume for 10 seconds • Android: Various combinations of power, home, and volume buttons • Ongoing problems may require a factory reset • Install latest operating system and reload

No sound from a particular app • Check volume settings • Both app and phone settings • Bad software / delete and reload • Try headphones Sound starts but then stops • Dueling apps / keep app in foreground No speaker sound from any app (no alarm, no music, no audio) • Load latest software or factory reset

Check settings to enable GPS • iOS: Settings / Privacy / Location Services • Android: Settings / Location Configure location mode • iOS: Settings / Privacy / Location Services • Android: Settings / Location / Location mode Need a good view of the sky • You're listening to satellites in space

Buildup of gas • Designed to self-contain • Do NOT open the battery packet/container • Significant fire risk • You'll be sorry Faulty battery • Stop using immediately • Dispose of properly The device can be damaged • Better than having a fire

Different than working on a desktop computer • Many different pieces • Intricately engineered • Tight quarters Taking it apart is easy •Getting it back together... Easy to break something • Very delicate parts

Document and label • It seems obvious when disassembling • It's not obvious at all when assembling • Check iFixit and similar sites Cable locations • There are a lot of cables • Antennas, drives, video, etc. Screw locations • There are a LOT of screws • Different sizes • "Hidden" locations

Laptops disassemble in sections • Outer shell, keyboard, video connector, etc Step-by-step • Take pictures • Use a big workspace Use containers to separate the sections • Glasses, boxes, etc • Magnetic grid • Multi-day projects should be sealed or protected

Refer to manufacturer resources • Often provide step-by-step repair guides The Internet provides the rest • Online written guides, YouTube videos Specialized sites can help - http://www.ifixit.com/

Use appropriate hand tools • Sometimes a single screwdriver • Get a good tweezer • Sometimes specialized tools Magnification will be needed • Smaller and smaller devices Get a big anti-static cloth • Something soft to protect screens • Easy to break tiny parts

Print or scan a test page • Built into Windows • Not the application Use diagnostic tools • Web-based utilities • Built into the printer • Vendor specific • Download from the web site • Generic • Available in LiveCD form

Streaks and blurs • Inkjet: Clean print heads • Laser: Check for scratched photosensitive drum Faded prints, blank pages • Low toner or ink Ghost images • Laser printer optical drum not cleaned properly • Ghost or "shadow" from previous drum rotation

Color prints in wrong print color • Low ink in one cartridge • Everything else works fine Laser printer output smudges everywhere • Toner not fused to the paper • Should be permanently melted and pressed • May not be hot • Fuser problem

Careful when removing • Don't rip the paper • Don't damage internal components Paper not feeding • Check the tray • Pickup rollers • Part of a laser printer maintenance kit Creased paper • Problems in the paper path • Check the paper weight

No connectivity • Powered on? • User intervention required • Wired cabling / Wireless settings Access denied • Security tab • Print • Manage this printer • Manage documents

Garbled characters on paper • Bad printer driver / wrong model • Incorrect page description language • (PCL or PostScript?) • Bad application • Check with a test page

Unable to install printer • Drivers are important OS updates • User must have proper rights • Check the printer driver • 32 bit vs. 64 bit Backed up print queue • Print server not working • Print spooler crash • Restart the spooler • Change recovery options

Error codes • On the printer display • Today's printers have large LCDs Low memory errors • Laser printers build the entire page in memory • Complex images and graphics consume more memory

Check the printer • Getting power? Check for display messages • Run a test print from the printer Check the connectivity • Print a test page from a computer • Check the direct connection • Try across the network • Tests the operating system, network, drivers, and spooler Check other applications • Print from a different program

Corrupted print jobs • Print spooler will crash • Most spooler configuration will automatically restart Problems are logged • Windows Event Viewer, Windows-PrintService One job may be causing the issue • Monitor the queue for details

Do you have a link light? • Is it plugged in? Ping loopback (127.0.0.1) • Is the protocol stack working? • Availability and intermittent connectivity Ping local IP address • Checks local configuration, adapter, and link signal Ping default gateway • Connectivity on the local network Ping devices on router's other side • 8.8.8.8

A link-local address • No forwarding by routers IETF has allocated 169.254.1.0 through 169.254.254.255 • 169.254.0.0/24 and 169.254.255.0/24 are reserved Automatically assigned • Uses ARP to confirm the address isn't currently in use Check your IP address • Is it an APIPA address?

Shares • Server unavailable • Share permissions have been modified • Relies on DNS to find the server Printers • Device sharing printer (or printer) is unavailable • Printer permissions have been modified Email • Service is associated with a specific server • May be a cluster of servers • Problems may be related to the servers or the network path

Windows alert in the system tray • "Limited or No connectivity" • "No Internet Access" Check the local IP address • An APIPA address will only have local connectivity If DHCP address is obtained, perform the ping tests • Local gateway, remote IP address

Internet access • Then nothing Check the system tray • A broken LAN icon is a loss of signal • Check for a cable problem • Might have bad network interface Problem with switch or wireless access point • Bad interfaces • Router rebooting

DHCP helps • But static addresses can conflict Windows will identify a duplicate • And prevent a conflict Two identical IP addresses will conflict • Intermittent connectivity, if any Reboot or reset the NIC • Start over from the beginning

Frustrating to the user • Challenging to the technician Router or infrastructure congestion • Overloaded network or devices Speed and duplex incompatibility • An easy fix Hardware issue with the adapter • Or your cabling • Malware infection

Interference - Something else is using our frequency Signal strength • Transmitting signal, transmitting antenna, receiving antenna, etc Incorrect channel • Usually automatic; look for manual tuning Bounce and latency • Multipath interference; flat surfaces Incorrect access point placement • Locate close to the users

Predictable • Florescent lights • Microwave ovens • Cordless telephones • High-power sources Unpredictable • Multi-tenant building Measurements • Signal strength • Performance Monitor

Network name doesn't appear • Other networks are there Too far away • Local networks are louder Wireless router has disabled SSID advertisements • It will never appear on a list • You can still manually connect