A Quick Definition of SIP
SIP stands for Session Initiation Protocol and is the most popular protocol used to handle multimedia sessions over networks and the internet. Telephony companies commonly refer to SIP lines as SIP Trunks. These are offered by many providers with different levels of service and experience. There are many options for SIP compatible phone systems , PC phones, device softphones, and IP handsets. SIP Trunks can be bought wholesale, they can be bought one off, or they can be part of a service. An open IP PBX should be able to use multiple SIP service providers, PRI’s, and other telephony related services at the same time, allowing companies the ability to protect themselves from service failures, or route calls along the most inexpensive provider.