CUCM CUBE and SIP setting

[Kosi227]

Hi all,

Recently we have project deploy a CUCM 10.5 and CUBE (Cisco3925)  with SIP connection to ISP:

CUCM  (10.10.10.1)-> (10.10.10.2)CUBE(192.168.10.10)-->(192.198.10.20)CE Router -->(172.10.10.1)ISP

we set a default route in that CUBE that point all traffic to CE router and it will auto route to ISP SIP Server

unfortunately , after we set up everything, China telecom tell us that ,we need to use a specified source IP to send out the SIP traffic to ISP and received the call. 

Normally we can add one more layer 3 device between the CUBE and CE Router to handle this, but we already purchased everything and the schedule is too tight..

so any suggestion that can solve it? can we make NAT in the CUBE ? 

CUCM  (10.10.10.1) --> (10.10.10.2)CUBE---> 192.168.10.254 --->(192.168.10.10)-->(192.198.10.20) CE Router --> (172.10.10.1) ISP

Thanks!

[Anthony Holloway]

Yes, not only can you NAT CUBE, putting it in your DMZ behind a firewall is best practice.

You'll just want to make sure you use an application layer gateway, or deep packet inspection, so the IP addresses deep within the SIP message are modified, and not just the layer 3 source/destinations.

Check out this guys' blog post on the matter, it's quite good.

http://ucpros.net/configure-cisco-cube/

[Kosi227]

thanks for your help.

finally we solved it as we make a loop back in my CUBE for the destination ip

however, we meet other issue after we testing the sip.

we found that the call will intermittently drop or mute via the sip from isp. maybe only 1 can success connected  in 4 calls

i check up the log it seems is related to the codec issues..please refer to my log in attached

do you have any idea about it?

thanks!