PRI Lines: The Advantages and Limitations

In 2018, your customers still want to call your business.

The most common reason people pick up the phone is to get a question answered quickly or to talk to a real human, according to a recent Google study. Understanding that phone calls still matter for customer service and employee collaboration is a pretty simple idea.

What’s less straightforward is choosing the right type of phone system for your business. With options like PRI Lines, SIP Trunking, and VoIP, simply keeping all of the acronyms straight is difficult. Selecting the option that will offer the most value for your business is even more complex.

If you’re trying to understand the advantages and limitations of PRI Lines, you're in the right place. PRI technology has some distinct pros and cons, each of which can impact companies in different ways. Read on to determine if PRI or an alternative is the best choice for your organization.

What are PRI Lines? What are My Alternatives to PRI?

Primary Rate Interface (PRI) is a telecommunications standard which has been used to support voice communications among businesses and consumers for over 40 years. PRI is used by telecommunications providers to transmit voice communications and data as electrical pulses over copper cable infrastructure and networks.

PRI Lines generally refer to a PRI circuit, a business technology used in conjunction with private branch exchange (PBX) systems. A single PRI circuit has 24 lines, which support 23 concurrent voice calls and one data channel for caller ID and other call-related data.

To install, add new lines, or upgrade existing PRI lines organizations must coordinate with a PRI technician or telecommunications carrier for on-site servicing of equipment and upgrades to the copper cabling infrastructure in the building.

Alternatives to PRI Technology

PRI Lines are an alternative to IP (internet) phone systems, including SIP Trunking, voice-over-IP (VoIP) or Cloud-Based PBX phones. PRI Lines may also be an alternative to an investment in Unified Communications as a Service (UCaaS).

To learn more, we recommend PRI vs. SIP Trunking: What’s the Difference and Which is Best?

The Advantages and Limitations of PRI Lines

PRI Lines have both advantages and disadvantages for business communications. As a widely-used standard for transporting voice communications for over 40 years, PRI phone systems are generally reliable and low-risk.

However, there are also fewer and fewer options for hardware and support due to the increased popularity of cloud-based phone systems for business. In an increasingly app and cloud-driven world, PRI isn’t an internet-compatible technology which can blend into a business technology ecosystem. Compared to cloud-based phone systems, scaling up PRI Lines can be expensive.

The relative impact of these pros and cons can vary depending on your company, vision, budget, and desire to switch to cloud-based communications.

The Advantages of PRI Lines

• Does not rely on IP data connectivity to support voice communications.
• Voice communications quality are not sensitive to shared data bandwidth.
• Can offer improved reliability with the installation of a redundant PRI circuit for failover.
• May align with IP-based phones to support legacy technologies such as fax machines, elevators, or alarm systems in a hybrid implementation.
• Could be the most reliable option for voice communications for businesses with limited access to Fiber-Optic Internet or high-speed data connectivity.
• PRI calls are not exposed to internet security risks since data is transmitted over physical infrastructure.

The Limitations of PRI Lines

• Require dedicated capacity. Adding one may require purchasing a 23-line circuit.
• Scaling and adding lines to PRI phone systems is much costlier to upgrade than cloud-based phone systems.
• Relies on physical infrastructure, which is expensive and slow to upgrade.
• Monthly service is likely to exceed the cost of IP-based phone service significantly, especially for long-distance and international calling.
• Subject to security risks, including call interception and interference.
• Not fail-safe and do not offer mobile failover in case of emergency or disaster.
• Expert PRI technicians, hardware, and support are becoming increasingly rare due to increased enterprise adoption of SIP and cloud phones.
• Does not offer technological interoperability for UCaaS.

Should You Consider Moving to SIP Trunking?

If your organization is trying to decide whether PRI or SIP is the right choice, there are many factors which should influence your decision. Ultimately, the correct answer depends on your company, your goals, and your current satisfaction and investment with existing phone systems.

What is your current phone system?

If your legacy PBX is reaching end-of-life and you're facing a lack of ongoing support or help with your phones, it may make sense to transition to SIP or UCaaS.

Alternatively, if your organization has recently purchased a new PBX system, it may make the most sense to maximize your existing investment in a costly technology before switching entirely to SIP.

What are your goals for Unified Communications and mobile transformation?

Organizations with a need for employee mobility, global collaboration, multimedia communications, or other benefits of UCaaS may benefit from an immediate switch to a SIP solution.

You can upgrade SIP with multimedia communication features, including mobility, screen-sharing, video-conferencing, and applications to merge voice, data, and collaboration. A PRI system only supports voice communications and cannot be integrated.

How much scalability do you need?

With PRI lines, organizations may need to wait weeks for upgrades. Adding lines can only be implemented in units of 23 lines by purchasing a PRI circuit.

In contrast, IP-based phone systems allow companies to add and subtract phone lines on demand without having to perform any significant modifications to infrastructure. Generally, billing is flexible and determined on a monthly basis by the features and number of lines in use.

To learn more, read into 6 Things to Know About Migrating From PRI to SIP.

Is Investing in PRI Lines the Right Choice?

A business phone system is a significant investment, and ideally, one which will serve your company for years. Before you purchase new PRI Lines, it’s important to understand the advantages and limitations of this technology compared to alternatives such as SIP trunking and Unified Communications in the cloud. While every company is different, most organizations find that PRI is both costlier and more limited than other options.

For many organizations, SIP Trunking as a primary mode of voice communications is less expensive over time. It’s easier to scale IP-based phone lines in the cloud, and it doesn’t require weeks of waiting or extensive upgrades to physical infrastructure. Switching to cloud-based business phone systems offers many businesses flexibility and the ability to scale technology on demand.

Before you choose a phone system or provider, it’s important to know the right questions to ask to make sure you’re selecting the right technology and vendor. For expert insight, download the free eBook: 10 Questions to Ask Before You Buy Phone Service for Your Business.