Voice Over Internet Protocol (VOIP)

Interoperability

Standards are still emerging that ensure VOIP features work with different vendor solutions. The H.323 standard is the one most widely deployed and is the only approved protocol adopted by the International Telecommunications Union (ITU). The H.323 standard provides support for audio calls to other H.323 clients, gateways, gatekeepers and conference servers. Another emerging standard is the Session Initiation Protocol, or SIP. Look for products that are adopting these two standards.