RIP Version 2 Protocol Analysis (RFC1387)
Original Publication Date: 1993-Jan-01
Included in the Prior Art Database: 2000-Sep-12
Internet Society Requests For Comment (RFCs)
As required by Routing Protocol Criteria (RFC 1264), this report documents the key features of the RIP-2 protocol and the current implementation experience.
Network Working Group G. Malkin
Request for Comments: 1387 Xylogics, Inc.
RIP Version 2 Protocol Analysis
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard. Distribution of this memo is
As required by Routing Protocol Criteria (RFC 1264), this report
documents the key features of the RIP-2 protocol and the current
The RIP-2 protocol owes much to those who participated in the RIP-2
Working Group of the Internet Engineering Task Force (IETF). A
special thanks goes to Fred Baker for his help on the MIB, and to
Jeffrey Honig for the implementation experience.
1. Protocol Documents
The RIP-2 protocol description is defined in RFC 1388 . This memo
suggests an update to the "Routing Information Protocol" (RFC 1058)
. The RIP-2 MIB description is defined in RFC 1389 .
2. Key Features
While RIP-2 shares the same basic algorithms as RIP-1, it supports
several new features. They are: routing domains, external route
tags, subnet masks, next hop addresses, and authentication.
2.1 Routing Domains
Routing domains allow multiple RIP "clouds" to exist over the same
physical network. This is a feature requested by several members of
the working group. It allows simple policies to be constructed by
grouping routers into domains which share routing information.
2.2 External Route Tags
The route tag field may be used to propagate information acquired
from an EGP. The definition of the contents of this field are beyond
the scope of this protocol. However, it may be used, for example, to
propagate an EGP AS number.
2.3 Subnet Masks
Inclusion of subnet masks was the original intent of opening the RIP
protocol for improvement. Subnet mask information makes RIP more
useful in a variety of environments and allows the use of variable
subnet masks on the network. Subnet masks are also necessary for
implementation of "classless" addressing, as the CIDR work proposes.
2.4 Next Hop Addresses
Support for next hop addresses allows for optimization of routes in
an environment which uses multiple routing protocols. For example,
if RIP-2 were being run on a network along with another IGP, and one
router ran both protocols, then that router could indicate to the
other RIP-2 routers that a better next hop than itself exists for a
One significant improvement RIP-2 offers over RIP-1, is the addition
of an authentication mechanism. Essentially, it is the same
extensible mechanism provided by OSPF. Currently, only a plain-text
password is defined for authentication. However, more sophisticated
authentication schemes can easily be incorporated as they are