The first, the Succession Communications Server for Enterprise (CSE) 1000 server, is an evolution of the company's Meridian PBX line and is intended for large enterprises.
For branch offices and smaller offices, Nortel has also released version 2.5 of its Business Communications Manager system. The release will let enterprises run IP phones directly on user desktops.
Consisting of both hardware and software, Business Communications Manager includes IP telephones, a Lan switch to provide quality of service, and a software component to provide advanced call centre and unified messaging applications.
The Lan switch, which works by prioritising voice traffic and monitoring and correcting latency, will let companies provide IP telephony services without expanding bandwidth.
Users will be able to install telephone features on their laptop computers for mobile phone access.
Some analysts believe that VoIP adoption is slow because companies do not perceive any qualitative advantage over conventional phone systems.