Level 3 Communications claims the top spot in IHS Markit’s 2016 Session Initiation Protocol (SIP) Trunking North America Service Provider Scorecard.

Listed in the scorecard, in alphabetical order, were AT&T, CenturyLink, Fusion, IntelePeer, Level 3, Sprint, Twilio, Verizon, Windstream and XO Communications. The scorecard identified companies best positioned to succeed long term.

Rankings are based on criteria such as the number of IP-connectivity trunks, financial stability, market strategy, service capabilities and support options.

“For the first time, Level 3 leads the SIP trunking market in this year’s scorecard with the largest installed base of trunks,” said Diane Myers, IHS Markit’s senior research director for VolP, UC and IMS. “Following Level 3 are Verizon and CenturyLink in a tie, with only a small difference in installed base. AT&T and XO round out the top five.”

Although the installed base of SIP trunks is important to the overall leadership score, financial stability also has a measurable impact on the standings, according to IHS Markit.{ad}

“Level 3 rose to the top this year, in part due to consolidated growth including the tw telecom assets along with an improved financial position,” Myers said.

Innovations in the SIP trunking market over the past year include new wireless capabilities, SIP connections over Long-Term Evolution (LTE) and SIP connections optimized for specific cloud-collaboration services, such as Cisco Spark.

“The top providers in our scorecard are consistent mainstays in this market, steadily growing their installed bases of trunks,” Myers said. “One new addition this year is Twilio, widely known for its communication application programming interface (API) enablement. Twilio has steadily built a SIP trunking business with no legacy services to cannibalize and a unique go-to-market strategy.”