CellStack Systems
Design and manufacture the ATM CellStack, product family, for high quality audio, video and data to be used on any ATM infrastructure.
Newbridge Networks
http://www.newbridge.com/solutions/technologysummary.jhtml?%2Falcatel%2Femk%2FUser.technology=ATM&am
Newbridge manufacturer of ATM switches and are now owned by Alcatel.