SIP trunking or Unified Communications: Which should you deploy first?

Posted on December 5, 2014 by Andrea Mocherman

It’s time to streamline your communications and collaboration processes, and take control of your connections. You’re evaluating Unified Communications platforms, and researching the most cost effective way to replace your legacy switch and PRI-based voice connection. You’ve learned that UC and SIP trunking go hand in hand, and the business case is crystal clear. But when it comes to choosing a priority, you’re wondering which transition to roll-out first. It’s an important question to ask because the answer reveals the right way to implement UC.


The match made in heaven:

I won’t waste time selling the virtues of UC or SIP trunking, we’re beyond that. You know as well as everyone else paying any amount of attention that the future favors IP-based voice and collaboration. Cisco calls SIP “the dominant rich communications protocol for IP networks” such as Unified Communications systems. They go together like Macs and black turtleneck sweaters – destiny.

It’s not surprising that companies that are deploying, or have deployed, Unified Communications are much more interested in SIP trunking than those that have no investment in UC. Talk to any UC consultant and they’ll tell you that conversations about implementation inevitably lead to SIP trunking. But that doesn’t mean Unified communications should come first.

The deciding factors:

What we need to look at is what the implications are of deploying one first over the other. In a post on, industry analyst Jon Arnold, ranked the benefits of the two as this, “VoIP is primarily about cost savings, UC’s validation comes from improving productivity.” He added, “You should be thinking about Unified Communications as Act II for VoIP.”

What it comes down to is the role. In a 2010 post on No Jitter that still holds weight, Lisa Pierce said, “SIP Trunk services act as the glue to support multi-location VOIP, IM, web or IP video conferencing applications.”

Paul Desmond echoed Lisa’s sentiment in an article for PCWorld last month when he wrote, “SIP is crucial for enabling UC applications including presence and advanced features such as the ability to transfer a call from a mobile phone to a laptop-based soft phone without dropping it.” The fact is, SIP trunking enables the transport of many media types (voice, video, text, file sharing,…) which makes it ideal for businesses implementing a unified collaboration solution.

The winner:

It’s a question of preparedness and ROI. SIP trunking is relatively easy to implement, and the payoff is usually very quick, and very tangible. While UC builds the requirement for a SIP trunking connection, SIP trunking actually lays the foundation for key UC functionality. Any savvy IT manager will tell you to focus on one big technology shift at a time. Putting UC first means you either have to defer the significant benefits afforded by SIP trunking, or endure the pain (and risk) of concurrent technology roll-outs. By setting up a SIP trunking service first, you’ll see immediate cost benefit and set the stage for a smooth transition to Unified Communications.