The Internet Real-Time Laboratory

Size: px

Start display at page:

Download "The Internet Real-Time Laboratory"

Alexina Maxwell
5 years ago
Views:

1 IRT 1 The Internet Real-Time Laboratory Henning Schulzrinne Dept. of Computer Science Internet Real-Time Laboratory (IRT) Columbia University New York, New York schulzrinne@cs.columbia.edu November,

2 IRT 2 Overview 13 PhD students, 2 visitors, 5 MS students, 14 project students goal: design & build network protocols, algorithms and software for enabling new services on the Internet themes: Internet multimedia and telephony wireless services service location and directories content distribution security

3 IRT 3 What is Internet Telephony? carriage of real-time voice and multimedia IP: private networks or public Internet interconnected to existing phone network low latency, high availability likely to start replacing existing phone system in ß ten years landline and mobile ( third-generation wireless )

4 IRT 4 Columbia Efforts in Internet Telephony signaling protocols: SIP + extensions (QoS, mobility, events, caller preferences,...) programming languages and interfaces: CPL and sip-cgi software and hardware VoIP platforms million calls/hour locating services and servers statistical packet voice characterization combining forward error correction (FEC) and playout delay adaptation

5 IRT 5 Events: SIP for Appliances SUBSCRIBE door@alice.home.net SIP user agent NOTIFY alice@work.com DO light@alice.home.net INVITE camera@alice.home.net SIP proxy (RGW) (Work with Telcordia)

IRT 6 Columbia Internet Extensible Multimedia Architecture

media server NMS analog FXO PC NT sipgw RTP SIP Sun Solaris

messaging server sipum NMS T1/E1 RTP SIP sipgw MySQL user

6 IRT 6 Columbia Internet Extensible Multimedia Architecture LDAP server sipconf conferencing server (MCU) rtspd RTSP media server NMS analog FXO PC NT sipgw RTP SIP Sun Solaris PC Linux/FreeBSD/NT sipd proxy/redirect server RTSP unified messaging server sipum NMS T1/E1 RTP SIP sipgw MySQL user database PhoneJack interface e*phone sipc SIP H.323 converter sip h323

7 IRT 7 Columbia e*phone DSP-based, single-processor Ethernet phone; being commercialized

8 IRT 8 Ad-Hoc Wireless Networks meet people walking subway airports, train stations,... and exchange data wirelessly web pages, music, images, applets,... Napster without wires information spreads rapidly in dense urban areas searchable by type, URL and content

9 IRT 9 files, glimpe index get request for data search engine return summaries store incoming web pages web browser search request request URL deliver from proxy cache or from network automatically request new "interesting" URLs proxy server request for data not in cache response from network request from other users response from cache display page listing all available information, dynamically generated by proxy server requestor periodic request for data summaries from network UDP multicast UDP HTTP over TCP

10 IRT 10 Quality of Service make sure important Internet traffic get through need resource reservation protocols YESSIR, BGRP, RNAP QoS pricing for adaptive multimedia services need management infrastructure

11 IRT 11 Examples of Spring 2001 Projects Linux device driver enhancements for wireless networks; speech recognition for Internet telephony; shared web browsing; mobility proxy; virtual reality conferencing system; audio delay and quality measurements; anonymizer for Internet telephone calls; pricing network resources; Internet radio station; hgs/teaching/project/spring01.html

The Columbia University SIP Suite: CINEMA

CINEMA 1 The Columbia University SIP Suite: CINEMA Henning Schulzrinne Internet Real-Time Lab Dept. of Computer Science Columbia University New York, New York http://www.cs.columbia.edu/irt schulzrinne@cs.columbia.edu