CGU SIP VC Client: Design, Architecture & Demo

Dr. Samir ChatterjeeNetwork Convergence Laboratory

School of Information Science

Claremont Graduate University

Claremont, CA 91711

909-607-4651; sip:samir.chatterjee@cgu.edu

Acknowledgments

• Network Convergence Lab at CGU– Bengisu Tulu, Tarun Abhichandani, Haiqing Li, Jongbok Byun

• National Science Foundation Grant (NMI Proposal 0222710)

• Internet2 and ViDe Net Folks– Jill Gemmill (UAB, Birmingham)– Tyler Johnson (UNC, Chapel Hill)– Egon Verharen (SURFNET)– Ken Klingenstein (Internet2)– Dynamicsoft Inc (SIP partner)

SIP (The IETF Standard)

• Session Initiation Protocol is a signaling standard approved by IETF for real-time multimedia session establishment.

• Sessions can be voice, video or instant messaging and is described by SDP.

• Basic components:– User Agent (UA): works on behalf of users to set up calls– Proxy Servers (PS): keeps track of location of end-points– Registrar: Each UA registers to inform current location and

preferred reachability information

• SIP also has been approved for 3G wireless systems.

SIP Operation

Sip:samir@cgu.edu

Cgu.eduProxy/registrar

Unc.eduProxy/registrar

Sip:alice@unc.edu

LS LS

REGISTER sip:registrar.cgu.edu SIP/2.0 Via: SIP/2.0/UDP samirspc.cgu.edu:5060;branch=z9hG4bKnashds7 Max-Forwards: 70 To: Samir <sip:samir@cgu.edu> From: Samir <sip:samir@cgu.edu>;tag=456248 Call-ID: 843817637684230@998sdasdh09 CSeq: 1826 REGISTER Contact: <sip:samir@192.0.2.4> Expires: 7200 Content-Length: 0

INVITE sip:Samir@cgu.edu SIP/2.0Via: SIP/2.0/UDP pc33.atlanta.com;branch=z9hG4bKnashds8Max-Forwards: 70To: Samir <sip:samir@cgu.edu>From: Alice <sip:alice@unc.edu>;tag=1928301774Call-ID: a84b4c76e66710CSeq: 314159 INVITEContact: <sip:alice@pc33.unc.edu>Content-Type: application/sdpContent-Length: 142

Dynamicsoft SIP Stack Architecture

DsUtil Library

SIPMessage

API

Low-level API State Machine

Mid-level API State Machine

High-level API

SDPMessageAPI

Optionalfor low-Level, Mid-level And JAIN API

JAIN API

Source: Dynamicsoft SIP User Agent Manual Java Version 5.4 and C++ Version 5.2

JMF Architecture

Source: Java Media Framework API Guide, November 1999.TM: Sun Microsystems Inc.

CGU SIPClient v1.1 Architecture

• We use two packages– Utils package maintains existing SIP calls– CGU Client package that handles SIP calls,

media and GUI part

• These packages interact with Dynamcisoft SIP libraries, SDP and JMF for media handling.

Audio/Video Codecs

• Audio– G.723– GSM– DVI law

• Video– H.261– H.263– JPEG

User Registration Process

http://ncl.cgu.edu/sipclient/index.php

• Bengisu (in DC) calls Liha (in Claremont)– Audio connection established– Video connection established

• Liha calls Bengisu– CallerID explained

• Bengisu calls Liha– Liha redirects to Nadim– Bengisu receives redirect and calls Nadim– Redirect to a web page

• Show ED and commobject

CGUsipClientv1.1 Demo

Future Directions• Client’s Next Release

– Authentication with password stored in LDAP– Enabling Firewall/NAT support

• Plan to use STUN, UPnP – Click to dial from commObject directory– Getting away from commercial SIP

• Client built on open source (Vovida), open source proxy

• Performance Enhancements– Load measurements– Media performance

• Use wavelet codecs• Test against SIP-based MCUs

– Further Integration with LDAP• Federated Security

– Role-based authorization using OpenSAML– Experimenting with digital certs (KX.509)