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One way voice traffic through PIX


I have a setup where a PIX is installed between router and call manager. The router is connected to PSTN. But when I make a call from outside to inside only one way traffic is there, ie I can here voice from ip phone but not the other way. I tried by configuring skinny protocol in PIX as suggested by cisco but still the same result. I also allowed udp traffic in PIX.

Can anyone suggest the solution for this problem.

thanks and regards



Re: One way voice traffic through PIX

Since there has been no response to your post, it appears to be either too complex or too rare an issue for other forum members to assist you. If you don't get a suitable response to your post, you may wish to review our resources at the online Technical Assistance Center ( or speak with a TAC engineer. You can open a TAC case online at

If anyone else in the forum has some advice, please reply to this thread.

Thank you for posting.

New Member

Re: One way voice traffic through PIX

We actually experienced this at the NYC City Hall. For instance, we had a PIX OS @ 6.1.1 at a remote location (501 Series) and a 6.1.1 520 at the Data Center. We created crypto maps and the like. We ran into this case we opened...

Problem Description: Truoble with IP Phone through PIX to PIX (Dynamic to Static) VPN. Can receive incomming calls to DID but can not place outbound calls from VoIP phone.


we are using nat (inside) 0 access-list 101 where 101 is referencing Home Office network to internal office network 10.128.228&224.0 and

Again, can receive incomming calls w/o issue but can not place outbound calls. Phone hangs and resets for some reason - One way voice issue.

At the time, the bug issued to us was a new one way back in retrospect:

The infamous CSCdv26953

New Member

Re: One way voice traffic through PIX

I forgot to mention. The fix was to use the interim build: (On both PIX's! It allows blocked messages in CCM to go through). They said it would be fixed, along with an assortment of other killer issues, in public release build 6.2 which, I was told, was due out at the end of March...Any ideas on when this build is due? For now, maybe research this bug and see if it represents your issue. CSCdv26953

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