By adding this capability, the MSO's business services arm will be able to provide the scalability and centralized management many enterprises are seeking as they move away from PBXs based on time division multiplexing (TDM) and toward those that support IP technologies. This number is on the rise. According to research by OneVoice, 65% of businesses are using SIP, and the number of SIP trunking users is expected to grow more than five times by 2017.
"The good news is that the way we built our voice portfolio, we are not necessarily religious about SIP or PRI or otherwise," said John Guillaume, VP product management for Comcast Business. "Depending on the customer's needs, we have a solution that slots in and solves the problem for them, whatever they are trying to achieve."
The business cycle for a PBX has historically been between 8-12 years, but this is shrinking. Companies looking to replace their existing systems might choose to outsource to a cloud-based solution, which involves no capital expenditure, because they do not purchase a PBX. However, if they want a physical asset, they most likely will use an IP-based PBX with SIP trunking to connect to the network, Guillaume said. "It is the best choice. It is more efficient and scales better .... Businesses are able to centralize (the PBX) and take the benefit of economics that comes along with that."
If a company is headquartered in Chicago, for example, but has 15 locations spread out across the United States, the PBX utilizing SIP trunking could be in Chicago and all handsets connected over a wide-area Ethernet solution. Cost savings come from not having to purchase 15 separate PBXs. The PBX can also be oversubscribed and, therefore, the business can buy fewer call paths, Guillaume said.
The addition of SIP trunking to the Comcast Business portfolio was "fairly easy," since the company had already built an all-IP network for its phone solutions. "SIP has been a protocol in the network for the better part of a decade," Guillaume said. "It was a matter of the right edge device and certifying newer PBXs that could support SIP."
Comcast serves both small and large businesses by allowing as few as six call paths to be purchased and can scale up to 800 call paths. "You could see that serving a location with 5,000-7,000 people in it," Guillaume said.