1. IP telephony @ Columbia Prof. Henning Schulzrinne Internet Real-Time Laboratory Department of Computer Science Columbia University

2. Sep 25, 2003 Cinema/demo2 Overview Multimedia communication Audio, video, text, screen sharing, … PSTN interworking, IVR, … Multi-devices IP-phone, telephone, X10, Ncast, … Collaboration Voicemail, discussion forum, …

3. Sep 25, 2003 Cinema/demo3 Point to point call Telephone network SIP/PSTN gateway SIP server IP endpoint Telephone subscriber +1 212 9397040 sip:wenyu@cs.columbia.edu sip:7141@cs.columbia.edu SIP “forking” proxy

4. Sep 25, 2003 Cinema/demo4 Multimedia conferencing Telephone 7040 SIP/PSTN Gateway Department PBX Web based configuration Web server SQL database sipconf Conference server NetMeeting H.323 siph323: SIP-H.323 translator Video encoder IP phones (cisco, grandstream) Soft phones (sipc, jsipc, messenger)

5. Sep 25, 2003 Cinema/demo5 Non real-time collaboration Voicemail Answering machine on no-answer or busy Auto-attendant to access Inbox Web interface Configuration and profile

6. Sep 25, 2003 Cinema/demo6 Messaging and device control DO sip:stereo@cs.columbia.edu SIP/2.0 ….. tune AM 103K lamp X10 device SIP MESSAGE sip:lamp@cs.columbia.edu SIP/2.0 ….. turn on

7. Sep 25, 2003 Cinema/demo7 sipd Ubiquitous computing

8. Sep 25, 2003 Cinema/demo8 Emergency service E-911 calls Location of the caller Audio, video, text Notification

9. Sep 25, 2003 Cinema/demo9 Summary SIP-based architecture Heterogeneous endpoints Telephone, SIP phone, H.323 Devices like lamp, video encoder Advanced services Programmable call routing, voice mail, interactive voice response Multimedia collaboration Synchronous: conference, IM Offline: discussion board, voicemail, file sharing