Siemens Enterprise OpenStage 40 SIP IP-phone is a great solution for people working in the permanent place. This model features a large display and easy setup of various protocols such as TDM, HFA and SIP.
IXC Softwitch is a high performance scalable Class 4 VoIP Softswitch solution with user friendly GUI web interface, which enables secure large VoIP traffic flow over various IP networks.