Avaya, IBM

The two other significant players in the UC&C market are IBM and Avaya.

IBM ranked No. 3 for total UC&C market share for Q4, pulling in around $360 million in sales. In comparing IBM to the broader UC&C market, Duke said: "We see IBM's trend as being minimal growth, but satisfying in servicing its large installed customer base."

Avaya, who recently filed for chapter 11 bankruptcy, came in third for premise-based market share, grabbing a solid 8.5 percent share. "While Avaya has certainly stacked up its challenges, we do not believe their potential or the power of their installed base should be under played," said Duke.