SIP Trunking

Take advantage of VoIP without replacing your current PBX

SIP: Session Initiation Protocol

SIP is the technology used to carry voice calls over a data network. A SIP Trunk is a virtual line based on Voice over IP technology (VoIP) that uses your internet connection to manage incoming and outgoing calls when connected to a local phone system (PBX). These phone lines are “software” based, and not delivered physically but through your internet connection.

In summary, SIP Trunking is a great option for organizations who want to take advantage of VoIP’s features such as unlimited calling and lower costs, but are not yet ready to take their phone system entirely to the cloud. Instead, they only replace the traditional phone lines with VoIP, moving one step toward the cloud.


Say goodbye to toll and long distance charges with GreenLink SIP plans!


With GreenLink, your existing PBX is able to take advantage of VoIP technology, using an internet connection to transmit calls instead of physical phone lines. This means you don’t have to pay the ever increasing cost of traditional phone service.

Instead, your existing PBX is hooked into the almost free internet highway. The benefits are instant:

  • Unlimited calling within the U.S., Canada and Puerto Rico
  • Ability to add phone numbers in any U.S. area code
  • Add trunks as your business grows, without waiting for installers to run new lines
  • Up to two open channels per SIP trunk, potentially doubling your call capacity
  • Ability to add SIP even if your PBX is not SIP compatible

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