Techniques for facilitating operation of a communication device having a first internet protocol (IP) address in a first network and a second IP address in a second network include detecting a presence of a network address translation (NAT) table; implementing, when the NAT table is present, a message exchange protocol to obtain a mapping between the first IP address and the second IP address; and reporting, in a communication message, the mapping between the first IP address and the second IP address. In one operational scenario, the first network is a 3 GPP network and the second network is a broadband fixed network such as a DSL or a cable modem network.