SIP Trunking Redux
Every Thanksgiving or so I hear someone ask the question, “Why does Butterball spend so much money teaching us to cook turkeys? Surely, everyone now knows how to do it by now!” Not really since every year is the first year for thousands of people to attempt to prepare their first turkey or they ruined it last year or they simply want to fix it differently. Therefore, every year thousands need assistance to make the Thanksgiving feast the best it can be and Butterball knows that. So, much like Butterball, I realize that there are legions of VARs and business owners who do not know why SIP Trunking saves money and improves communications services. Because of that, I intend to spend this week revisiting the subject.
First, SIP Trunking is not necessarily cheaper that using a PRI. A T1 can support 23 voice channels when configured as a PRI. SIP Trunking with a G.711 codec can support a maximum of 18 voice channels or concurrent call sessions (CCSs). The cost savings enjoyed by converting T1s from PRIs to SIP Trunks is due to the creation of a converged circuit or facility. A converged circuit can support voice and data simultaneously. By combining voice and data, a business can maximize its broadband utilization. This prevents businesses from maintaining separate circuits for voice and data which often result in underutilized bandwidth causing a business to over spend for its communications and data requirements. Additionally, voice capacity can be added a single voice channel or concurrent call at a time. In the case of PRIs, the addition of voice capacity is 23 channels (plus a data channel) at a time. Thus, the cost to add a single or a few voice channels can be quite expensive. Finally, with Ethernet over copper (EoC) a converged circuit can have bandwidth added in a broad array of increments from single to multiple megabits at a time.
The cost savings achieved through the conversion of PRIs to SIP Trunks is dependent upon the network architecture, circuit utilization, data requirements and, whether there is a plan to leverage Unified Communications, video conferencing or cloud computing. No single or average amount of savings can be declared just because a business transitions from PRIs to SIP Trunks. Moreover, if the business decides to use compression, a G.729a codec, then the same bandwidth that supports 18 CCSs can now support 48 CCSs, thus dramatically changing the cost analysis.
So, what justifies the Broadvox and ITSPs claim for up to 70% savings?
We’ll explore that on Wednesday.