Cisco Systems Router 1800 Series User Manual

 
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Appendix A      Cisco IOS Software Basic Skills
  Understanding Command Modes
Ta b l e A-2 Command Modes Summary 
ModeAccess MethodPromptExit and Entrance MethodAbout This Mode
User EXECBegin a session with 
your router.Router>To exit a router session, enter 
the logout command. Use this mode for these tasks:
 Change terminal settings.
 Perform basic tests.
 Display system information.
Privileged...

 
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Appendix A      Cisco IOS Software Basic Skills
  Getting Help
Getting Help
You can use the question mark (?) and arrow keys to help you enter commands.
For a list of available commands at that command mode, enter a question mark:
Router> ?
access-enable Create a temporary access-list entry
access-profile Apply user-profile to interfaceclear Reset functions
...
To complete a command, enter a few known...

 
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Appendix A      Cisco IOS Software Basic Skills
  Enable Secret Passwords and Enable Passwords
Enable Secret Passwords and Enable Passwords
By default, the router ships without password protection. Because many privileged EXEC commands are 
used to set operating parameters, you should password-protect these commands to prevent unauthorized 
use. 
You can use two commands to do this:
 enable secret...

 
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Appendix A      Cisco IOS Software Basic Skills
  Using Commands
Using Commands
This section provides some tips about entering  Cisco IOS commands at the command-line interface 
(CLI).
Abbreviating Commands
You only have to enter enough ch aracters for the router to recognize the command as unique. This 
example shows how to enter the  show version command:
Router # sh v
Undoing Commands
If you want to...

 
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Appendix A      Cisco IOS Software Basic Skills
  Saving Configuration Changes
Saving Configuration Changes
You need to enter the copy running-config startup-config command to save your configuration changes 
to nonvolatile RAM (NVRAM) so that they are not lost if there is a system reload or power outage. This 
example shows how to use this command to save your changes:
router# copy running-config...

 
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Appendix A      Cisco IOS Software Basic Skills
  Where to Go Next 

 
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APPENDIXB
Concepts
This appendix contains conceptual information that may be useful to Internet service providers or 
network administrators when they configure Cisco routers. To review some typical network scenarios, 
see 
Chapter 2, “Sample Network Deployments.” For information on additional details or configuration 
topics, see Chapter 11, “Additional Configuration Options.”
The following topics are...

 
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Appendix B      Concepts
  SHDSL
SHDSL
SHDSL is a technology based on the G.SHDSL (G.991.2) standard that allows both data and voice to be 
transmitted over the same line. SHDSL is a packet-based network technology that allows high-speed 
transmission over twisted-pair copper wire between a network service provider (NSP) central office and 
a customer site, or on local loops created within either a...

 
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Appendix B      Concepts   PPP Authentication Protocols
RIP and Enhanced IGRP differ in several ways, as shown in Ta b l e B-1.
Ta b l e B-1 RIP and Enhanced IGRP Comparison
ProtocolIdeal TopologyMetricRouting Updates
RIPSuited for topologies with 
15 or fewer hops.Hop count. Maximum hop 
count is 15. Best route is one 
with lowest hop count.By default, every 30 seconds. 
You can reconfigure this value...

 
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Appendix B      Concepts
  PPP Authentication Protocols
(start/stop) and bit-oriented synchronous encapsulation, network protocol multiplexing, link 
configuration, link quality testing, error detection, and option negotiation for such capabilities as 
network-layer address negotiation and data-compression negotiation. PPP supports these functions by 
providing an extensible Link Control Protocol (LCP) and...