Which of the following are characteristics of a Frame Relay point-to-point subinterface? (Choose
two.)
A.
resolves NBMA split horizon issues
B.
requires the frame-relay map command
C.
maps one IP subnet per DLCI
D.
maps one IP subnet across multiple DLCIs
E.
requires use of Inverse ARP
Explanation:
Frame Relay networks fall under the umbrella of Non-Broadcast Multi-Access (NBMA) networks.
As the name implies, these networks allow multiple devices to access the network, but do not
allow broadcast between them. Although this is their default behavior, you can configure your
Cisco router to treat the network however you’d like. Because NBMA networks allow traffic
between only the sites for which you purchase PVCs, this leads to some very odd configurations.
The hub and spoke topology can be very confusing to manage until you understand the problems
associated with these network types.
One of the major problems that can be encountered is that of running distance vector routing
protocols over a Frame Relay network. These routing protocols (which include RIP, IGRP, and
even EIGRP) have a built-in loop prevention mechanism called split-horizon . This mechanism
prevents a router from sending an update out the same interface as that on which it received an
update