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Despite its overhaul, RIP v2 could not compensate for all its
predecessors limitations. In fairness to the creators of RIP v2, they
did not seek to make RIP v2 anything but a modernized RIP. This
included maintaining its original purpose as an Interior Gateway
Protocol (IGP) for use in small networks or autonomous systems.
Therefore, all the original functional limitations designed into RIP
also apply to RIP v2. A critical difference is that RIP v2 can be used
in networks that require either support for authentication and
variable-length subnet masks.
Some of the more significant limitations that were inherited by RIP v2
include the following:
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Lack of alternative routes – RIP v2 continues to maintain a
single route to any given destination in its routing tables. In the
event a route becomes invalid, the RIP v2 node does not know any
other routes to the destination of the failed route. Consequently,
it must wait for a routing update before it can begin to assess
potential alternative routes to that destination. This approach to
routing minimizes the size of routing tables but can result in the
temporary unreachability of destinations during a link or router
failure.

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Counting to infinity –
RIP v2 continues to rely on counting to infinity as a means of
resolving certain error conditions within the network. One such error
condition would be a routing loop. RIP v2 remains dependent on timers
to generate updates. Therefore, it is also relatively slow to converge
on a consensus of the network topology following any change to that
topology. The more time that
it takes to converge, the greater the opportunity for obsolete
information to be mistakenly propagated as current information. The
result could be a routing loop.

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15-hop maximum – Perhaps
the single greatest limitation that RIP v2 inherited from RIP is that
its interpretation of infinity remained at 16. After a route cost is
incremented to 16, that route becomes invalid, and the destination is
considered unreachable. This limits the use of RIP v2 to networks
with a maximum diameter of 15 or fewer hops.

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Static distance vector metrics –
Another inherited limitation is found in the RIP v2 static cost
metrics. The default value of 1 is just like RIP. However, the
default value can be manually adjusted by the network administrator. This metric remains constant, and can only
be changed by the administrator. Therefore, RIP v2 remains unsuited
for network environments that require routes to be selected in
real-time based on either delay, traffic loads, or any other dynamic
network performance metric.
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