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774 Appendix A: Answers to the "Do I Know This Already?" Quizzes and Q&A Sections
41
Configure ISDN interface BRI1, assuming that it is attached to a DMS-100 ISDN switch,
that it uses only one SPID of 404555121201, and that you want to screen calls so that only
calls from 404555999901 are accepted.
isdn switch-type basic-dms100
interface bri1
isdn spid1 404555121201
isdn caller 404555999901
The switch-type command is required. The SPID(s) is required only with some switches.
The isdn caller command is needed only for call screening.
42
Name the configuration command used to enable FRF.9 compression on a point-to-point
Frame Relay subinterface.
The frame-relay payload-compress frf9 stac command enables FRF.9 compression on
a Frame Relay subinterface.
43
List the types of compression that are available on PPP links.
The STAC, Predictor, and MPPC compression types are available on PPP interfaces in the
IOS.
44
Describe the decision process performed by the IOS to attempt to dial a connection using
legacy DDR.
First, some traffic must be routed out the interface to be dialed; this is typically
accomplished by adding static routes pointing out the interface. Then, interesting must be
defined; any packets routed out the interface that are considered interesting will cause the
interface to be dialed.
45
If packets from 10.1.1.0/24 were "interesting" in relation to DDR configuration, such that
packets from 10.1.1.0/24 caused a DDR connection out an interface BRI0, list the
configuration commands that would make the IOS think that those packets were
interesting on BRI0.
The access list that follows defines the packets from 10.1.1.0/24. The dialer-list defines
the use of access-list 1 for deciding what is interesting. The dialer-group command
enables that logic on interface BRI0.
access-list 1 permit 10.1.1.0 0.0.0.255
!
dialer-list 2 protocol ip list 1
!
interface bri 0
dialer-group 2
apA.fm Page 774 Monday, March 20, 2000 5:24 PM