We have an EX60 deployed in an enterprise environment, and it's sitting behind a NAT. We

can register it directly to a CUCM 10.5 system within the same enterprise. However, because

the EX60 is deployed behind a NAT, the IP address that shows up on CUCM is its internal

address (192.168.0.x), not the external IP address (192.168.209.35) that represents the devices

behind the NAT. And so it follows that video calls result in one way audio and video,

(audio/video appear on the far end but not the EX60) because the far end system thinks it

should be sending traffic to the internal IP instead of the external address of the EX60.

We have some special circumstances that prevent us from moving the EX60 out from behind

the NAT.

Does this type of deployment require something else in the UC mix like an

Expressway C, even though the endpoint and the CUCM are located within the same

enterprise? Or some other CUCM configuration setting?

We've been trying to add SIP firewall aware modules for the NAT (nf_conntrack_sip and

nf_nat_sip) and they don't seem to be helping our situation.

Thanks in advance for any advice/suggestions

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