Lead Inventor: Henning Schulzrinne, Ph.D.

Problem or Unmet Need:
As the Internet has grown, so too has use of the Internet for telephony. Compared to conventional circuit-switched telephony, Internet telephony offers a number of advantages. Using internet telephony, one can select how to encode and compress his/her calls to ensure an optimal quality/price ratio. Because calls could be placed with varying qualities, Internet telephony would not be as burdened by network overloads as conventional telephony.

Currently internet telephony is beset by a number of unintegrated protocols, such as the Wireless Applications Protocol for internet access form wireless devices, the Short Message Standard for text messaging, and Bluetooth for wireless communication between nearby devices. A need also exists for a low-cost internet telephony appliance that uses simple protocols, unlike the H.323 signaling and control protocol currently in use. This technology details a low-cost internet telephony appliance and a simple set of signaling protocols it can use.

Details of the Invention:
The technology consists of a packet-based voice communication system that may be used over Internet and intranet telecommunications networks. The network telephony appliance includes a network controller coupled to a data network for providing and receiving data packets to and from the network, a digital signal processing subsystem for detecting incoming calls and initiate call sessions, a signal conversion subsystem for converting between digital and analog signals, and a user interface subsystem. The network telephony device would optimally use the Session Initiation Protocol (SIP).

Applications:
• Low-cost Internet and intranet communications
• Appliance can also support continuous or streaming media such as Internet radio or television

Advantages:
• The telephone may be made completely wireless
• Call packets may be encoded and compressed according to the user's needs
• High-level telephony functions such as call-forwarding, multiparty calling, and voice mail may be readily integrated

Patent Status: Patents issued and Pending (US 7,610,384; US 6,970,909; WO/2002/031669; WO/2000/076158; US20100002690A1; US20090290695A1) ~ see links below.

Licensing Status: Available for Licensing (CA, CN, & IL rights) and Sponsored Research Support

Publications: Rosenberg, J., Lennox, J., and H. Schulzrinne. Programming Internet telephony services. IEEE Internet Computing. 3:63 (1999).

Schulzrinne, H. and L. Rosenberg. The Session Initiation Protocol: Internet-centric signaling. IEEE Communications Magazine. 38: 134-141 (2000).


Other Links:

• WIPO_1 - WO/2000/076158
• WIPO_2 - WO/2002/031669
• USPTO_3 - US20090290695A1
• USPTO_4 - US20100002690A1
• USPTO_1 - US 6,970,909
• USPTO_2 - US 7,610,384

Further Information
Calvin Chu
Email: TechTransfer@columbia.edu

File Number: MS98/04/16