The Devil is in the Details of Large-Scale SIP Trunking

By Amanda Ciccatelli, TMCnet Web Editor

Did you know that sales of IP Communication are expected to grow significantly over the next few years? In fact, according to Gartner (News - Alert), 1/3 of North American enterprises use SIP trunking today, and that number is expected to grow to 40 percent by 2014.

One business in particular recently deployed an outbound dialer for its contact center operations using SIP Trunks. It needed more calls pushed out and the current service couldn’t handle the required calls per second ratio. So, with the help of NACR, an independent integrator of communications solutions and services, the business decided to install a larger Ingate SBC to handle higher call rate.

However, there were some challenges that occurred while deploying the SIP solution. The trunk groups couldn’t handle more than two calls per second and the dialer required 25 calls per second, so NACR added more trunk groups to load balance across these groups to accommodate the call requirements.

“But, the outbound dialer could not load balance. It would slam the first trunk group and not across all of them. Everything went into chaos and it couldn’t accommodate calls,” explained Thomas Roel of NACR in the Ingate SIP Trunking-UC Seminar, this afternoon in Miami.

So, Roel and NACR put a session management platform in place to perform load balancing and added a new SBC to handle increased call flows.  “We achieved success by taking the using a new Ingate box, which handled the calls perfectly,” he said.

The bottom line is NACR’s customer spent millions of dollars on an outbound dialer product that they thought would work immediately, but the contact center ended up having some problems to overcome.

Overall, SIP trunking is a great medium for high volume of traffic, according to Roel, but you have to know what you are doing from start to finish when deploying a complete solution.

NACR and Roel learned a few things after successfully overcoming the deployment solution including:

• You can efficiently share trunk services with other traffic types like PBX (News - Alert)
• More traffic reports are needed in terms of call rate on all vendor participants
• SIP deployments of all types are a process, not a plug and play
• Know the specific goals and capabilities end-to-end

According to Roel, today NACR’s customer is highly satisfied with the SIP trunking solution’s easy administration. “The customer says the solution is very cut and dry, user friendly, and easy to work with.”

Edited by Brooke Neuman