x25 with OSPF

[omar.elmohri]

Do we can use OSPF with x25 links ?

while:

-A hierarchical topology is used

-Summarization is applied

-Zones are created

[Giuseppe Larosa]

Hello Omar,

OSPF is a routing protocol for IPv4 (OSPFv2) so you can use it if you have IPv4 on top of X25 links.

X.25 links are generally low speed and can take advantage of low bandwidth consumption of OSPF as compared to RIP.

An OSPF multi-area domain allows you:

to limit and control routing information inside each area.

to summarize routes at Area Boundary on ABR routers.

Hope to help

Giuseppe

[omar.elmohri]

Thank you Giuseppe,

I want to be sure that it's run with no problem.

I have X25 with minimum of 128kbps, so I think if I'll optimize with areas and summary routes, this will work fine.

Regards,

Omar

[Giuseppe Larosa · Accepted solution]

Hello Omar,

using stub areas where possible help to minimize the OSPF link state database size.

With totally stub area only an O IA 0.0.0.0/0 is sent representing all destinations outside the area.

If you need to inject routes in the remote routers you can consider to use not so stubby areas (NSSA).

Each LSA is refreshed every 30 minutes.

For this reason bandwidth comsumption is low.

There is RFC1245 that deals with relationships between number of routes and link usage

http://www.ietf.org/rfc/rfc1245.txt

Using the right tools you can have a dynamic routing protocol running over low speed links with no issues.

Hope to help

Giuseppe