Understanding PRI (Primary Rate Interface) and Upcoming Changes to this Technology

business phone

What Is Primary Rate Interface?

Primary Rate Interface — PRI — is an end-to-end connection for delivering commercial telecom services, including voice, data and video traffic. PRI is a subset of the ISDN standard, supporting 23 concurrent inbound/outbound bearer channels and one signaling channel, with CLID and DID service.

Delivered over T1 transmissions, PRI became the office standard once adopted by TelCo carriers and providers of PBX technology. In use since the 1980s, PRI may be nearing the end of its lifetime.

Changes With PRI

Looking forward, Primary Rate Interface may have peaked, as many current users are receiving notice from their carriers signaling an intent to discontinue service. By the last date of service, customers must migrate to a new service or system but may still be under contract with their carrier.

Additionally, many businesses have PBX systems designed and equipped to support PRI cards and licenses, representing a significant investment in company infrastructure.

What Is Happening to PRI?

PRI and the ISDN standard were introduced 34 years ago — ancient history by today’s standards. In this era, cable TV was still relatively new, and internet access remained limited to university campuses. Back then, 23 bundled channels across a PtP network were a more affordable alternative than running POTS lines across the same connection.

Today, users can transmit voice, television and internet signals over a single PtP connection to a business or their home. The simplicity of use and ease of integration is putting pressure on the PRI standard, and it’s getting more expensive to update the equipment and infrastructure to compete.

At the same time, revenue from landline telephone services is on the decline, and on-premise telephone companies are being phased out in favor of hosted systems and cloud-based services. On-premise systems rely on PRI service, but with fewer in use, demand for PRI service is down.

Options for Overcoming Changes in PRI

Whether responding to a letter from a service provider or taking proactive steps to maintain control over the transition, companies and organizations are switching to SIP (Session Initiation Protocol). SIP delivers all the same services as PRI, including CLID, DID and concurrent calling.

SIP supports a higher number of concurrent calls than PRI, and organizations can easily increase their call capacity in increments of one for their desired total. SIP is available as a bundled service from a single carrier for ease of integration or over an internet connection from an independent provider.

The Benefits of Switching to SIP

Switching to SIP offers more than an alternative to PRI, with benefits that include:

  • Redundancy: Users can take advantage of multiple circuits for voice delivery.
  • Bursting: You can exceed your maximum concurrent calls to accommodate peak calling.
  • Disaster attendant: If a disaster interrupts your business, SIP answers calls in the cloud and offers options to connect.
  • Out-of-market numbers: If you need to expand or accommodate new users, SIP trunking delivers out-of-market telephone numbers to your local corporate system.

Say Farewell to PRI

New phone systems are engineered to accept SIP, and for older systems, SIP migration projects leverage managed gateways to translate the new standard, keeping the phone system as-is and eliminating the need for significant upgrades. Another alternative is to replace an on-premises system with a hosted offering. Hosted systems include carrier services, eliminating the need for third-party SIP or PRI.

At Morefield Communications, we use smart technology solutions to help your organization grow, offering custom SIP services and more from a single provider. We offer the latest advancements in technology with the small-town feel of a neighborhood service provider. For over 70 years, we’ve built our reputation throughout Pennsylvania for expert service and care for our community.

To learn more about our services for businesses, organizations, nonprofits and more, connect with us online or call (717) 761-6170.

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