NV-600W Managed Wireless VDSL2 Router USER’S MANUAL Ver. A3
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RIP implements the split horizon, route poisoning and holddown mechanisms to prevent incorrect routing information from being
propagated. These are some of the stability features of RIP. It is also possible to use the Routing Information Protocol with
Metric-Based Topology (RMTI) algorithm to cope with the count-to-infinity problem. With RMTI, it is possible to detect every possible
loop with a very small computation effort.
RIP uses the User Datagram Protocol (UDP) as its transport protocol, and is assigned the reserved port number 520.
RIP version 1
: The original specification of RIP, defined in RFC 1058, was published in 1988 and uses classful routing. The periodic
routing updates do not carry subnet information, lacking support for variable length subnet masks (VLSM). This limitation makes it
impossible to have different-sized subnets inside of the same network class. In other words, all subnets in a network class must have
the same size. There is also no support for router authentication, making RIP vulnerable to various attacks.
RIP version 2
: Due to the deficiencies of the original RIP specification, RIP version 2 (RIPv2) was developed in 1993 and last
standardized in 1998. It included the ability to carry subnet information, thus supporting Classless Inter-Domain Routing (CIDR). To
maintain backward compatibility, the hop count limit of 15 remained. RIPv2 has facilities to fully interoperate with the earlier
specification if all Must Be Zero protocol fields in the RIPv1 messages are properly specified. In addition, a compatibility switch
feature allows fine-grained interoperability adjustments.
