[OSPF] Increasing the maximum number of links advertisable in a single Router LSA

Vlad Olariu <florinvlad.olariu@gmail.com> Mon, 04 April 2016 12:27 UTC

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From: Vlad Olariu <florinvlad.olariu@gmail.com>
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Subject: [OSPF] Increasing the maximum number of links advertisable in a single Router LSA
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Hello All,

Considering what the OSPFv2 RFC states:

A.4.2 All of the router's links to the area must be described in a single
> router-LSA.


The maximum number of links advertisable in a single Router-LSA for a
single LSA is around 5K.

Following this, I have two questions:
> How come the* # links* has 2 bytes, allowing for up to 65536 links?
> Is there any way to bypass the 5K limit?

Thank you.

P.S This is of course just an exercise. I don't expect any sane network
design to require that many links in the same area.