Router/ASA with IP un-numbered. Now need SIP into equation.

[l33byt1980]

Hi,

Have a 2MB leased line which we use for internet and Email.
This is via a serial interface with IP un-unumbered to an ASA 5505.

Now we have a telephone system which supports SIP and I would like to utilise this to do so, however I believe we will have a NAT issue here as we will need to do some work with port 5600.

Can this be done with my set up

ACA - IPOffice implement
ACA - IP Telephony
CCNA - Passed at last

 

[routerman]

Probably, although you really need to put some more detail on this. There is an article on cisco.com that may offer a solution to your issue, have a look at this:

http://www.cisco.com/en/US/products/ps6120/products_configuration_example09186a008081042c.shtml

This describes running the VoIP across a VPN, but the main point is that the SIP inspection (on the PIX/ASA) sniffs the session channel and opens up the ports that are negotiated at session establishment.