Shipments of Internet Protocol lines in the second quarter were up 30% from a year earlier, according to Dell’Oro Group.

That growth was driven largely by small businesses, which picked IP for a quarter of all voice line shipments during the quarter.

That migration will accelerate thanks to the efforts of vendors such as Avaya, Cisco Systems and Nortel Networks, Dell’Oro said.

Nortel led worldwide shipments during the quarter, followed by Avaya. But despite a record quarter for Avaya in Europe, Cisco beat Avaya in North America in the quarter.