Cisco, HP join to open up voice networks.(Company Business and Marketing)

The giants of data networking, and at least one start-up, now are gearing up to take on the mighty public switched telephone network.

Hewlett-Packard and Cisco Systems last week kicked off a partnership designed to bring an open systems model to telephone services, and this week start-up Castle Networks will unveil an architecture to do largely the same.

The aim of both is to bring the open systems model of the data world to a voice network that has thus far been based on proprietary switches and software.

"Vertical integration in the telecom industry is a thing of the past," said Cisco President John Chambers.

HP and Cisco officials …