Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Community Member

NAT traversal for H.323 gateway

Hi!

I need help with following scenario: I have CUCM cluster in my private subnet with 192.168.1.0 addressing. Also I have 2821 gateway with 2 interfaces: one in 192.168.1.0 subnet and second interface resides in another subnet with real IPs. I need to create connection between CUCM and a H.323 GW in the outside network. How do I need to configure NAT on 2821 GW to allow inbound connections to pass to CUCM from the outside GW?

Thank in advance!

4 REPLIES
Community Member

Re: NAT traversal for H.323 gateway

Hi

You may want to consider static NATs for CUCM servers on the 2821 router. Also the below url will provide some information about the tcp/udp ports used by CUCM 7.0 if you are intending to configure the static NAT on the basis of ports.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/port/7_0/CCM_7.0PortList.pdf

Community Member

Re: NAT traversal for H.323 gateway

Hi,

Thank you for your reply. I have tried to establish static NAT, but unfortunately, this works in wrong way. I have no problems with signaling, but have problems with RTP, because RTP traffic goes between IP phones and external GW and I need to somehow establish dynamic NAT rules to forward RTP traffic to IP phones, instead CUCM.

Community Member

Re: NAT traversal for H.323 gateway

Hi

I'm not sure how your topology looks like, but i have a lab setup below that works, allowing the CUCM IP phones to call the CME phones and vice versa.

CUCM+IP phones -- NAT router --- h323 GW --- CME router --- CME phones

The CUCM+IP phones are in the "inside" network, and NAT router does static NAT for the CUCM and PAT for the IP phones. CUCM is configured with a route-pattern pointing to the h323 GW for the CME phone numbers. while CME has a dial-peer pointing to the H323 GW for the CUCM IP phone numbers. The h323 GW is effectively an IPIPGW and is configured with the appropriate dial-peers.

You may want to try to configure PAT for the IP phones, static NAT for the CUCM in the inside network to see if that works.

Community Member

Re: NAT traversal for H.323 gateway

Hi,

Topology is the same. I will try to do PAT, as you have suggested. Thanks.

1163
Views
0
Helpful
4
Replies
CreatePlease to create content