Selsius Systems

Selsius Systems was a telecommunications company in Dallas, Texas that developed and marketed some of the first IP telephony gear. It was co-founded by Richard Platt and David Tucker. Selsius was incorporated in 1997 and acquired by Cisco Systems in November, 1998.
Selsius designed an IP PBX system consisting of a line of IP phones, a server-based call control application - the Selsius-CallManager, a line of voice over IP gateways and voice applications including voicemail, an automated attendant console and a softphone.