What is SIP Trunking

SIP, or Session Initiation Protocol, is a communications standard that allows multiple endpoints to communicate with one another over Internet Protocol (IP). SIP is a powerful tool for businesses across the globe as they transition from traditional telephony products to Voice over IP (VoIP). By utilizing Primus' SIP Trunking, organizations benefit from scalability, flexibility, reliability and cost savings that traditional telephony does not offer.

Primus SIP Trunking is used to connect your IP PBX to Primus' managed cloud communications network for your voice communication. For businesses that don't have a SIP capable IP PBX, you can still leverage the powerful benefits of SIP by using a SIP Media Gateway device to convert the SIP protocol to a standard phone line or PRI that would connect to your existing equipment.

Our SIP Trunking service is fully scalable and flexible, allowing businesses to fully customize the service to meet their budget and business needs. This drives huge cost savings over traditional telephony, like a PRI, since you are no longer bound to a specified number of channels.

How It Works

Diagram of how SIP Trunking Works

The 3 requirements for SIP Trunking:

  • IP PBX or SIP Media Gateway
  • Data Network Access
  • Primus SIP Trunking

Primus SIP Trunking works over IP, meaning you are required to have a data network access that you can use to connect your IP PBX or SIP Media Gateway. SIP is a cloud-based service with no physical line delivered to your premise.

Primus offers you the choice of how to connect your SIP Trunking service to help better meet your budget and your business needs. As a full service provider of both data and voice services, we can also help you enhance your network as your business needs change.

You can choose one of the following ways to connect SIP Trunking within your network:

  1. Leverage an existing Internet access connection; it must have latent capacity you can leverage, for the lowest cost and fastest implementation. The existing connection can be provided by Primus or a 3rd party carrier.
  2. Use a dedicated Internet access connection supplied by a 3rd party that will only be used for SIP Trunking to minimize the effects of heavy data usage from other platforms.
  3. Use a dedicated Internet access connection supplied by Primus that terminates directly on Primus' network. This direct connection between your network and ours will help to minimize any impacts to voice quality due to heavy Internet usage between providers, while still allowing you to leverage powerful SIP failover and overflow options to further enhance availability.

To find out if you have a compatible IP PBX or SIP Media Gateway, see our list of Compatible Hardware.

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