Driven by competitive pressure and the desire for new service generating opportunities, major service providers have begun rolling out Voice over Internet Protocol (VoIP) services to business and consumer markets.

Some of the key components of network design for supporting VoIP are:

• Topological design: Core network topology, softswitch and router placement, and backhaul designed for reliability and scalability
• Capacity design: Softswitches, routers, facilities, servers, and other network elements to support voice traffic and signaling
• Signaling network design: Interconnecting voice end points independent of their access arrangements and corresponding signaling protocols (e.g., SIP, SS7, H.323, H.248/MEGACO, MGCP)
• QoS design: For end-to-end quality of service objectives for latency, jitter and packet loss, plus traffic policing, queuing, and shaping

In a few cases, the addition of VoIP traffic may not require significant modifications to the existing data network topology or router capacities; but signaling networking design and QoS designs represent new elements in traditional data network design.