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540 Chapter 14: SNA Topologies
Foundation Summary
This section is a convenient review of many key concepts in this chapter. If you are already
comfortable with the topics in this chapter, this summary could help you recall a few details. If
you have just read this chapter, this review should help solidify some key facts. If you are doing
your final preparation before the exam, Table 14-4 is a convenient way to review the day before
the exam.
Table 14-4
Five methos of controlling explorers
Caching
Statically define frequent NetBIOS names.
Explorer Firewall
Limit the amount of explorers that can travel across a link at one time.
Virtual Ring Numbering
Prevent explorers from being replicated.
Filtering
Filter unnecessary traffic.
Static
Allows a router to setup circuits without sending resources.
Table 14-5
Availability and response times for traffic
High Availability
150 milliseconds or less.
Normal Availability
1 Second or less.
Low Availability
2 Second response time.
Best Effort
5 Second response time.
Table 14-6
DSLw+ TCP Ports
TCP Port 2065
High priority--Circuit administration frames, keepalives, capabilities exchanges
TCP Port 1981
Medium priority
TCP Port 1982
Normal priority--Information frames
TCP Port 1983
Low priority--Broadcast frames
87200333.book Page 540 Wednesday, August 22, 2001 1:41 PM