SIP trunking is a service offered by network operators that provides enterprises with VoIP communications over a broadband connection to an on-premises PBX IP interface, all-IP PBX or IAD.
Session Initiation Protocol (SIP) is used to signal and control interactive communication sessions. The uses for such sessions include voice, video, chat and instant messaging, as well as interactive games and virtual reality. The SIP protocol is increasingly being used to provide Voice over IP, Presence and Instant Messaging in Next Generation Networks, and being mandated for many new applications, including 3G telephony. SIP can be used to control Internet multimedia conferences, Internet telephone calls and multimedia distribution, in both the core and the periphery of the communications network.
SIP trunks replace the older PSTN (Public Switched Telephone Network) trunks that network operators use to provide dedicated voice calling functionality to enterprises with an on-premises PBX (Public Branch Exchange).
Whereas PSTN trunks use circuit switched network infrastructure to deliver voice calls only, SIP trunks use a broadband IP connection to deliver voice calling based on VoIP (Voice over IP) along with data access and enhanced communications services.
SIP trunking is separated from entirely cloud hosted services like hosted PBX by the requirement for the enterprise customer to have an on-premises PBX with IP interfaces, an all-IP PBX or an IAD (Internet Access Device). SIP trunking is a helpful transitional technology that allows enterprises to benefit from enhanced communications services while continuing to draw value from existing investment in on-premesis equipment.
SIP trunking has many benefits over PSTN trunking, including:
- SIP trunks aren't limited to delivering voice calls. Network operators can also deliver unified communications and collaboration services over the same connection.
- PSTN trunk capacity is typically expensive and inflexible in periods of high demand. SIP trunks are much cheaper to maintain and much more flexible to accomodate changing demand.
- SIP trunks rely on broadband connections rather than on managed PSTN infrastructure so SIP trunking providers can enter geographic regions where they do not own and control the infrastructure.
To find out more about how CT CloudSIP trunking could work for your organization, contact CallTower for a demo today: