Juniper IGP - CONFIGURATION GUIDE V11.1.X, Configuration Manual

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to 16 for an unreachable network. This small range prevents RIP from being useful
for large networks.
RIP Messages
RIP exchanges routing information via User Datagram Protocol (UDP) data packets.
Each RIP router sends and receives datagrams on UDP port number 520, the RIP
version 1/RIP version 2 port. All communications intended for another router’s RIP
process area are sent from the RIP port.
Every RIP message contains a RIP header that consists of a command and a version
number. The router supports RIP version 1 (RIPv1) and RIP version 2 (RIPv2)
extensions.
RIP employs the following message types:
■
Request—A request for the responding router to send all or part of its routing
table.
■
Response—A message containing all or part of the sender’s routing table. This
message is sent in response to a request or is an unsolicited routing update
generated by the sender.
The RIP request and response messages also contain a list of route entries. Each
route entry contains the following:
■
Address Entry Identifier—The type of address
■
Destination IP address—The destination address of the message
■
Cost to reach the destination—A value between 1 and 15, which specifies the
current metric for reaching the destination
Platform Considerations
For information about modules that support RIP on the ERX7xx models, ERX14xx
models, and the ERX310 Broadband Services Router:
■
See ERX Module Guide, Table 1, Module Combinations for detailed module
specifications.
■
See ERX Module Guide, Appendix A, Module Protocol Support for information about
the modules that support RIP.
For information about modules that support RIP on the E120 and E320 Broadband
Services Routers:
■
See E120 and E320 Module Guide, Table 1, Modules and IOAs for detailed module
specifications.
■
See E120 and E320 Module Guide, Appendix A, IOA Protocol Support for information
about the modules that support RIP.
206 ■
Platform Considerations
JUNOSe 11.0.x IP, IPv6, and IGP Configuration Guide