Cisco Chapter 2 Flashcards
Network Operating System
Operating systems for routers
Enables device hardware to function
Provides an interface for users to interact
IOS
(Cisco) Internetwork Operating System
Operating Systems
Like Windows an OS
Shell
The user interface that allows users to request specific tasks from the computer. These requests can be made either through the CLI or GUI interfaces
Kernel
Communicating between Computer Hardware and Software
Home routers
OS = firmware
Shell
A command-line interface (CLI)
A CLI-based network operating system also used on Intermediary Network Devices
A graphical user interface (GUI)
mostly used for computers
primarily focus
you will focus primarily on Cisco IOS Release 15.x. The figure displays a list of IOS software releases for a Cisco Catalyst 2960 Switch.
Console
This is a physical management port that provides out-of-band access to a Cisco device. Out-of-band access refers to access via a dedicated management channel that is used for device maintenance purposes only. No configuration neccearly
SSH 22
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.
Encrypted passwords by id
Telnet 23
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.
Telnet server
Telnet client
AUX port
Legacy auxiliary port is out-of-band and does not require networking services to be configured or available.
Terminal Emulation Programs
An excellent terminal emulation programs available for connecting to a networking device either by a serial connection over a console port or by a SSH/Telnet connection.
EXEC
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.
Priveleged EXEC
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.