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New Member

Skinny NAT

The setup is as follows:

35 x 7940-------2610-------CCM/PSTN

Phones run Skinny and are Nat'ed to a single IP. Can anybody tell me if there are any restrictions specific to Skinny NAT (i.e. separate to Device Weighting)...

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New Member

Re: Skinny NAT

There are. You'll need to configure an application level gateway. "fixup sccp" needs to fix ip addressing at the application layer and this is not done by default. Why are your phones behind a NAT device?

New Member

Re: Skinny NAT

The phones are behind a NAT device since the CCM is shared between multiple customers- since there are 35 handsets they have private addresses and they have an overlapping address range with another customer. Also to avoid managing VPN/private address range routing in our core network.

I don't know whether you understood my question- the solution works without any problems, but since there are 35 phones behind the NAT device I am worried as to how scalable the solution is. What I was looking for was "You can have x concurrent calls"...

I'm not running any firewalls on the IOS and don't have a PIX therefore not using fixup protocol.