What is VoIP?

Voice over Internet Protocol (VoIP) is a protocol optimized for the transmission of voice through the Internet or other packet switched networks. VoIP is often used abstractly to refer to the actual transmission of voice (rather than the protocol implementing it). VoIP is also known as IP Telephony, Internet telephony, Broadband telephony, Broadband Phone and Voice over Broadband. "VoIP" is pronounced voyp. SIP, short for Session Initiation Protocol is an IP telephony signaling protocol used to establish, modify and terminate VOIP telephone calls. A VOIP gateway is a device which converts telephony traffic into IP for transmission over a data network. They are used in 2 ways: 1. To convert incoming PSTN/telephone lines to VOIP/SIP: In this manner, the VOIP gateway allows calls to be received & placed on the regular telephony (PSTN) network. 2. To connect a traditional PBX/Phone system to the IP network: In this manner the VOIP gateway allows calls to be made via VOIP. Calls can then be placed via a VOIP service provider, or in the case of a company with multiple offices, inter office calling costs can be reduced by routing the calls via the Internet. VOIP gateways are available as external units or as PCI cards. The vast majority of devices are external units. A VOIP gateway will have a connector for the IP network and one or more ports to connect the phone lines to it.