Core Issue
Routing Information Protocol (RIP) and Interior Gateway Routing Protocol (IGRP) are classful protocols. Whenever RIP or IGRP advertise a network across a different major net boundary, it summarizes the advertised network at the major net boundary.
Resolution
A discontiguous network is comprised of a major net separated by another major net. RIP version 1 (RIPv1) and IGRP do not support discontiguous networks because of the way they determine whether to accept a major network in an advertisement.
For more information, refer to Why Doesn't RIP or IGRP Support Discontiguous Networks?.
Type of Route to be Advertised / Redistributed Route
Major networks
