Welcome to the IRT Website


The Internet Real-Time Lab (IRT) in the Computer Science Department at Columbia University conducts research in the areas of Internet and multimedia services: Internet telephony, wireless and mobile networks, streaming, quality of service, resource reservation, dynamic pricing for the Internet, network measurement and reliability, service location, network security, media on demand, content distribution networks, multicast networks and ubiquitous and context-aware computing and communication.

About twenty graduate students and visitors are exploring various research areas under the guidance of Prof. Henning Schulzrinne, and closely interacting with the larger networking community at Columbia Networking Research Center (CNRC) as well as other research labs. We design and analyze new protocols, perform prototyping and measurements, pursue their standardization in the IETF and transfer technology to companies.

Some of the projects that are currently being researched at the IRT Lab include:

  • Session Initiation Protocol (SIP)
  • Application and Desktop Sharing
  • 7DS - Information exchange in disconnected networks
  • VoIP for wireless networks
  • Emergency services -- NG911
  • GloServ: global service discovery architecture
  • QoS measurement for VoIP
  • Peer-to-peer IP telephony
  • Training FAA using SIP and RTP
  • Over-the-top (OTT) video streaming analysis

For more details, have a look at all our projects or our publications.