Session Initiation Protocol (SIP) trunking is the next generation of telecommunications technology. Instead of using the conventional telephone trunk, SIP Trunk facilitates connections to the Public Switched Telephone Network (PSTN) over the Internet.

SIP is an internationally standardized way of initiating interactive multimedia user sessions on a trunk (a line or link that can carry simultaneous signals at once).

Advantages of SIP Trunk.

• Convergence of voice, data, and video on a common IP connection.
• Allows companies local points of presence in multiple cities rather than 1-800 numbers.
• Flexible call control with each employee having their own phone number or direct extension.
• Scalability without large capital expense or investment in on-premise infrastructure.
• Enhanced security if the enterprise selects audio encryption options.
• Significant cost saving

• Eliminates need for expensive gateway (Basic Rate or Primary Rate interface) subscriptions or desktop equipment.
• Reduces hardware support and maintenance costs.
• Curtails over subscription to voice channels

What does SIP Trunk require?

To install SIP trunks, the enterprise must have three things:

1. Voice over Internet Protocol (VoIP) private branch exchange systems (PBX)
2. Enterprise edge component (either a firewall or device connected to the firewall) understanding SIP
3. Internet telephony service provider (ITSP)

With SIP trunking your enterprise can communicate with fixed and mobile telephone subscribers while enjoying increased reliability and reduced costs thanks to, among other attributes, user-based pricing models.

Adopt SIP trunk technology and you’ll also gain new productivity enhancing features as realtime communications takes on a deeper meaning without geographical or technological constraints.