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SaedSalmanFlag for Jordan

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Enabling both of RIP and IGRP.. advantages, disadvantages, Risks

Hello Experts:

What is/are advantages, disadvantages and future risks of enbabling both of RIP and IGRP ??

Thanks in advance.
Saed Salman
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i_t

they're easy but no vlsm for one. slower convergence.
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Other than a little extra CPU and bandwidth load, there aren't any real advantages/disadvantages/risks of running both. It's really a question of you need to do.

Do you HAVE to run RIP and IGRP? If you do, then you need to enable both. If you don't then... don't.

Typically, one of the goals in routing is the run one routing protocol. Running multiple routing protocols increases the amount of work for the admin and the complexity of the configuration.

So unless you have to connect with routers running RIP and IGRP, pick a protocol.

I will say however that IGRP is no longer supported on the latest IOS version so there may be some support issues down the road.

And RIP is probably the most primitive of the routing protocols. So unless you have a relatively small network, you may want to consider EIGRP or OSPF.
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Its a question that my instructor asked me, And I need something theoretical,logical and ordered to say tomorrow.
provide me with more details please, I googled about thsi but did not find something useful.

I do know about IGRP and RIP and how they work, But I will not invent a new protocol.
Where does my instructor get his questions from ? Mars ?
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Don Johnston
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Thank you very much donjohnston,
but I will not tell him: more complex config and the additional overhead of two protocols.  ONLY

the reset of your post seems as a differentiation between RIP and IGRP.


> IGRP:
> +
> no 15 limitation
Yes, you are right, but there is alwayes an upper bound. For IGRP it is 50 :)

I appreciate you efforts, thanks again.
IGRP has a max hop count of 255. It's set to 100 by default.
probably stupid but
could rip poison a good igrp route?
No. RIP has an Administrative Distance (AD)of 120 while IGRP is 100.  AD is the deciding factor when you learn the same route through two different protocols.
I found this:

48.If both RIP and IGRP are enabled on a router, it will always use IGRP, as IGRP has higher precedence. Therefore, when using IGRP, disable RIP in order to spare resources.

Reference:
http://www1.pacific.edu/eng/courses/ecpe/ecpe177/fa07/Labs/Routing-Essentials.doc
First, it's called "Administrative Distance. Precedence is a completely different issue topic.

Second, if someone is running RIP and IGRP it is probably because they're communicating with a router running RIP and a different router running IGRP. So if you disable RIP and the IGRP router fails, you will have lost the alternate path to the destination.

Unless they're talking about running RIP and IGRP between two routers and that's something that there is absolutely no reason to do.
My Instructor should answer the question this Sunday, I will post his answer here and take an action ;-)
Thank you again