Introducing VoIP Gateways
Gateways provide a number of ways to connect an IP telephony network to the PSTN, a
legacy PBX, key systems, or other TDM systems. Gateways range from specialized,
entry-level, and standalone voice gateways to high-end, integrated routers and Cisco IOS
gateways. This section introduces voice gateways and deployment models in an IP telephony
network.