MGCP, MEGACO, and SIP VoIP Signaling Protocol Security Requirements
This document specifies the requirements that the MGCP, MEGACO, and SIP VoIP Signaling Protocols must satisfy in order to meet the needs for VoIP deployment in carrier class and large geographically distributed organization networks. These requirements were developed with a specific focus on network address translation (NAT), network through application layer packet filtering, signaling across multiple trust domains, and redundancy of call/controllers, media gateways, proxies and registrars.