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

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

Point to point call SIP “forking” proxy sip:wenyu@cs.columbia.edu +1 212 9397040 IP endpoint Telephone subscriber Telephone network SIP/PSTN gateway SIP server sip:7141@cs.columbia.edu SIP “forking” proxy Cisco phone dials 7040 to PSTN PSTN dials to 7141 to Grandstream phone Cisco phone dials 7141, forks to both Grandstream and Sipc/laptop. Sipc accepts the call. Sipc connects to another Sipc for IM, audio, video, VNC, white board, shared browsing Cinema/demo Sep 25, 2003

Multimedia conferencing Department PBX SIP/PSTN Gateway Video encoder Telephone 7040 IP phones (cisco, grandstream) sipconf Conference server SQL database Web server Web based configuration Soft phones (sipc, jsipc, messenger) NetMeeting H.323 siph323: SIP-H.323 translator PSTN dials 7149 to conference. Sipc dials 7149@sip2.cs.columbia.edu for audio/video. Another sipc, jsipc or messenger dials 7149@sip2.cs.columbia.edu for audio/video Ncast joins the conference for video. Cisco phone joins the conference, through auto-attendent (dial 2000). Grandstream phone joins through auto-attendent. Yi Qin joins using audio/video on sipc. Cinema/demo Sep 25, 2003

Non real-time collaboration Voicemail Answering machine on no-answer or busy Auto-attendant to access Inbox Web interface Configuration and profile Show leaving a voice mail on no answer and accessing using auto-attendant (need to test this?) Show web pages configuration for contacts, user list, message board, voice mail. Cinema/demo Sep 25, 2003

Messaging and device control X10 device SIP lamp Sipc does the device control for the lamps. DO sip:stereo@cs.columbia.edu SIP/2.0 ….. <Control> <Action>tune AM 103K</Action> </Control> MESSAGE sip:lamp@cs.columbia.edu SIP/2.0 ….. turn on Cinema/demo Sep 25, 2003

Ubiquitous computing sipd Cinema/demo Sep 25, 2003

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

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 Cinema/demo Sep 25, 2003