3dmentat - Fotolia
Verizon is the top SIP trunking provider for the seventh year in a row, while CenturyLink claimed the number two spot for the first time, according to the latest SIP trunking provider scorecard from IHS Infonetics Research.
IHS research director Diane Myers said Verizon claimed the top spot due to its large installed user base and strong financial stability. The provider has maintained its top ranking for the past seven years as it led development of enhanced capabilities, like bursting, she said.
The scorecard ranks the top 10 providers in the North American SIP trunking space using measurements including installed user base, financial stability, market strategy, service development and support options.
CenturyLink saw the biggest jump in the rankings, moving from the bottom of the pack to take the number two spot. Myers said CenturyLink has made a concerted effort to grow its VoIP business by making improvements to its financial stability, working with different partners and growing its user base.
"It gives them the ability to be more successful in the market to a broader base of companies," she said.
Other providers in the ranking are: XO Communications, AT&T, Cox Communications, Fusion, IntelePeer, Level 3 Communications, Sprint and Windstream.
The right SIP trunking provider is key to successful adoption
SIP trunking adoption in the enterprise continues to rise, according to the 2015-2016 Nemertes Research unified communications and collaboration benchmark. More than half of enterprises adopted SIP trunking this year and nearly 70% of enterprises will adopt SIP trunking by 2016, according to the report.
Cost savings was the leading driver for SIP trunking adoption, followed by the ability to burst, flexibility to scale up or down and more efficient use of bandwidth, according to the report.
For organizations looking to evaluate potential SIP trunking providers, Myers said to be sure to compare providers' apples to apples. The top six providers do not vary much, she said, but they differentiate on their services with pricing and packages.
Myers said enterprises should consider providers' services, cost, whether they can service any location, if they can support on-premises equipment and if they can use a session border controller (SBC) to support SIP compatibility.
Enterprises must also evaluate a SIP trunking provider's security offerings. Enterprises should question the security of a provider's network and whether that security translates to their own network.
"This is a big area businesses don't think about," Myers said. "They put firewalls and security on the data side, but they aren't thinking about it enough in the IP world -- not for voice."
Myers said SIP trunking roadmaps are also important in any evaluation. Enterprises should determine where they see their voice infrastructure in five years and question whether a potential SIP trunking provider can meet changing needs.
How well do you know SIP trunking?
Choosing between SIP trunking and PRI
The advantages of adopting SIP trunking