Cisco Ccna 1

Redundancy

With a QoS policy in place, the router can manage the flow of data and voice traffic, giving priority to voice communications if the network experiences congestion.

can be accessed from anywhere, less space, cheaper, lower overhead

to act as an intermediary between user and OS through GUI or CLI

Secure Shell (SSH) - SSH is a method for remotely establishing a secure CLI connection through a virtual interface, over a network. Unlike a console connection, SSH connections require active networking services on the device including an active interface configured with an address. SSH is the recommended method for remote management because it provides a secure connection. SSH provides encrypted password authentication and transport of session data. This keeps the user ID, password, and the details of the management session private. Most versions of Cisco IOS include an SSH server and an SSH client that can be used to establish SSH sessions with other devices.

User EXEC Mode ">" This mode has limited capabilities but is useful for basic operations. It allows only a limited number of basic monitoring commands but does not allow the execution of any commands that might change the configuration of the device. The user EXEC mode is identified by the CLI prompt that ends with the > symbol. Privileged EXEC Mode "#" To execute configuration commands, a network administrator must access privileged EXEC mode. Higher configuration modes, like global configuration mode, can only be reached from privileged EXEC mode. The privileged EXEC mode can be identified by the prompt ending with the # symbol.

All purpose break sequence. used to abort DNS lookups, traceroutes and pings.

Cisco IOS Layer 2 switches have physical ports for devices to connect. These ports do not support Layer 3 IP addresses. Therefore, switches have one or more switch virtual interfaces (SVIs). These are virtual interfaces because there is no physical hardware on the device associated with it. An SVI is created in software. The virtual interface provides a means to remotely manage a switch over a network using IPv4. Each switch comes with one SVI appearing in the default configuration "out-of-the-box." The default SVI is interface VLAN1.

encourages competition and promotes choices

assists in protocol design prevents technology in one layer from affecting other layers

segment

cancellation

not affected by EMI or RFI more expensive than UTP

provides high availability and connects some, but not all, remote sites

data link layer addressing detection of errors through CRC calc delimiting groups of bits into frames

receives entire frame and performs CRC check to detect errors before forwarding frame

retain contents when power is removed store the startup configuration file

*a single packet can be sent to a group of hosts *multicast transmissions can be used by routers to exchange routing information *routers will not forward multicast addresses in the range of 224.0.0.0 to 224.0.0.255

10.0.0.0 127. 192.168.0.0

converts ipv6 to ipv4

FE80::1/10

255.255.255.128

* .com