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Chapter 9
BGP Scalability and Advanced Features
A, B. Prefix lists use considerably less CPU space and are much easier
to configure than access lists. They cannot affect advertised routes
coming into an interface and are configured globally on a router, not
on each interface.
E. There is no such thing as a redistribution list using BGP. The other
ways listed are all valid ways of manipulating routes advertised by
B. You can increase the AS-PATH length by adding false AS numbers.
Although the ip bgp as-path value command and the set as-
path extended
command appear convincing enough, they are not
real commands. The bgp dampening command is used by BGP to set
a hold time before a route can be re-advertised after route
A, B. Statements are entered in a distribute list by configuring an
access list. The statements are processed in the order in which they
were entered and from the top down. Sequence numbers are not used
in distribute lists.
B. Sequence numbers are assigned in increments of five when no
sequence number was assigned when the prefix list statements were
C. BGP routers not participating in a route reflector client are called
non-client routers.
D. The COMMUNITIES attribute value can be any number between
1 and 4,294,967,200.
D. The sequence number is used in prefix lists. Confederations use
iBGP on routers in sub-ASes and then use eBGP to connect the sub-
B. The no ip prefix-list sequence-number command is used to
disable sequence numbering for prefix lists. The only other real com-
mand is the no ip prefix-list command, which is used to delete
a prefix list.
Copyright ©2001 SYBEX , Inc., Alameda, CA