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FWSM fixup infos for mgcp and skinny

Hi net pros,

Can someone point me to more information about the fixup engines?!

We have to secure a callmanager server farm behind a fwsm, running version - next week we will upgrade to

We would like to use the mgcp and the skinny fixup engines here.

I was told that last time it was tested the fwsm had 100% cpu load and they had to disable the fixup engines / they just opened a huge range of ports for the rtp traffic.

Found only this about performance, but its kind of old documentation: (

Fixup connections, rate: 10,000 per second.

PC based fixup connections, rate: 10K per second.

We have about 20000 phones but i doubt they all register in 1 second :-) so the performance should not be an issue.

So now I'm search for more performance charts and of course for documentation how the skinny/mgcp fixup engines really work (what messages they read / what ports are opened dynamically / sample setup etc.)

Any information appreciated

Best regards

Juergen Bauer


Re: FWSM fixup infos for mgcp and skinny

The information about the various messages which are related to mgcp and skinny are available in the following link

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