Cisco Systems CCNA 2 manual Module 8 Summary

Module 8 Summary

Before students begin Module 9, they should know where to look for many of the error messages they may encounter.

Online assessment options include the end-of-module online quiz in the curriculum and the online Module 8 exam. This is a very descriptive module so vocabulary or scenario-based quizzes may be the preferred form of assessment.

Students should understand the following main points:

•IP is a best-effort delivery method that uses ICMP messages to alert the sender that the data did not reach its destination.

•ICMP echo request and echo reply messages allow the network administrator to test IP connectivity to aid in the troubleshooting process.

•ICMP messages are transmitted with the IP protocol so their delivery is unreliable.

•ICMP packets have their own special header information, which starts with a type field and a code field.

•Potential causes of specific ICMP error messages

•The functions of ICMP control messages

•ICMP redirect/change request messages

•ICMP clock synchronization and transit time estimation messages

•ICMP information request and reply messages

•ICMP address mask request and reply messages

•ICMP router discovery message

•ICMP router solicitation message

•ICMP congestion and flow control messages

100 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Module 8 Copyright ♥ 2004, Cisco Systems, Inc.