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SIP Trunking Should Be a No Brainer

SIP trunking is popular, cost effective, and it has beneficial features compared to T1 and PRI access. Large numbers of SIP installations continue to take place year after year from many different VARs, providers, and PBX and SBC vendors. Yet, four out of five installations have one or more problems, according to The SIP School's 2016 SIP Survey.

SIP Trunking is Attractive

SIP trunking attracts a lot of attention. In some cases, you cannot connect to new T1 or PRI trunks so SIP trunking is your only choice. But often, businesses choose to implement SIP trunking to receive a number of benefits. SIP trunking usually:

  • Lowers costs compared to T1/PRI trunks
  • Creates a flexible service
  • Offers new services such as free on-net (SIP to SIP) calling
  • Delivers flexible business continuity

While these goals are valid, SIP Trunking is not as "plug-and-play" as the traditional T1 and PRI trunks, so enterprises should expect more trouble tickets along the way.

Implementation Best Practices

In the end, the responsibility for a successful SIP trunk implementation rests with you and your IT and network staff. These best practices can help to ensure a smooth implementation:

  • Be clear about your objectives and the key indicators that will demonstrate you have met the objectives.
  • Ask, ask, ask questions! If you make assumptions, you are responsible for them, not the vendors and providers.
  • Coordinate with the vendor(s) and provider(s). Have them all meet together with the enterprise staff tasked with the implementation.
  • The problems discussed in the "SIP Survey 2016" are the most common challenges that will be encountered, so anticipate them. Do not be surprised if they occur during the implementation.
  • It is a good idea to trial the SIP trunk service first. Work out the kinks then, not when you go live. Unfortunately not everyone does according to The SIP Survey 2016. Just take a look at the graphic below from The SIP School's report.


There are a few other things that you should keep in mind throughout the SIP implementation process. The following tips should help you stay on track:

  1. Have a good test plan. Assume your implementation is unique no matter what the vendors and providers state.
  2. There can be differences in SIP protocol headers, in error codes, and DTMF signaling requirements, even blockage of 911 calls.
  3. Verify the software releases to be used.
  4. Fax works differently with nearly every SIP trunk provider. Plan extra time for interoperability testing.
  5. Ensure you have current and adequate documentation and configuration guides from all parties involved in the implementation.
  6. Look for management tools from the vendors and providers that support reporting for capacity planning, voice quality, service levels, and security.
  7. Do not expect the time allocated will be enough. Budget some time for unanticipated issues.

Are You Ready for SIP Trunks?

If you're not sure if you're ready or are in the planning stages of a SIP trunking implementation, I'll be leading a case studies session at the upcoming Enterprise Connect Orlando that you won't want to miss, "SIP Trunking Case Studies: Current Challenges and Opportunities." I'll be moderating a panel discussion that includes Larry Riba, Lead Voice Engineer, TIAA and Mark Reynolds, Associate Director, IT Department, University of New Mexico.

We'll be addressing some key questions, including:

  • What are the most important issues to be aware of in SIP Trunking procurement in 2017? Which carriers are leading the way in cost-effective offers and (relative) ease of implementation?
  • What new issues have arisen over the generations of technology, service, and regulatory issues since SIP Trunks first emerged?
  • How do you make sure your enterprise has staff with the skills to run a UC service that borrows heavily from legacy PSTN concepts?
  • What should your plan for SIP Trunking rollout look like, depending on your architecture, traffic patterns, and resiliency/disaster recovery needs?

Previous Enterprise Connect SIP Trunking sessions have been highly interactive, drawing a large audience, so I do hope you'll come and attend the panel discussion.

To prep yourself as you head into Enterprise Connect, read my other blogs that provide more details from "The SIP Survey 2016:" "SIP Trunk Providers Still Learning" and "SIP Trunk Equipment Still Needs Work."

Learn more about SIP and SIP trunking at Enterprise Connect 2017, March 27 to 30, in Orlando, Fla. View the SIP/SIP Trunking track, and register now using the code NOJITTER to receive $300 off an Entire Event pass or a free Expo Plus pass.