26
Larry Amiot Northwestern University [email protected] Internet2 Commons Site Coordinator Train September 27, 2004 Austin, Texas Introduction to SIP

Larry Amiot Northwestern University amiot@northwestern

Embed Size (px)

DESCRIPTION

Introduction to SIP. Larry Amiot Northwestern University [email protected]. Internet2 Commons Site Coordinator Training September 27, 2004 Austin, Texas. How Do We Communicate?. Telephone (home, work, & cell phone) Email Text messaging - PowerPoint PPT Presentation

Citation preview

Page 1: Larry Amiot Northwestern University amiot@northwestern

Larry AmiotNorthwestern [email protected]

Internet2 Commons Site Coordinator TrainingSeptember 27, 2004Austin, Texas

Introduction to SIP

Page 2: Larry Amiot Northwestern University amiot@northwestern

2

How Do We Communicate?

Telephone (home, work, & cell phone) Email Text messaging Data sharing (PowerPoint, applications,

white board, desktop, etc.) Audio/video File transfer Ink- tablet PC

Page 3: Larry Amiot Northwestern University amiot@northwestern

3

Questions?

…but how do we know where to find the person we want to communicate with

...and given the availability of my resources, which of the persons devices do I want to communicate with

..and what is the address of that device ..and how does the person control his

active/inactive devices ..and how do we authenticate people ..and how do we bridge this between

organizations

Page 4: Larry Amiot Northwestern University amiot@northwestern

4

Enter the Session Initiation Protocol (SIP)

An emerging signaling protocol for: • Initiating,• Managing, and • Terminating messaging, voice, and video sessions

Internet Engineering Task Force (IETF)• Developed by the SIP Working Group• Published as IETF RFC 3261

Connectivity using IP May be extended for services such as:

• call control services, • mobility,• interoperability with telephony systems, and more

Page 5: Larry Amiot Northwestern University amiot@northwestern

5

SIP and its Extensions

Presence• The willingness and ability of a user and their devices to communicate with other users on the network

• SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE)

AuthenticationOffice integration

Page 6: Larry Amiot Northwestern University amiot@northwestern

6

SIP Entities

User Agent• User Agent Client (UAC)• User Agent Server (UAS)

Redirect ServerProxy Server Registrar

Page 7: Larry Amiot Northwestern University amiot@northwestern

7SIP Session Establishment and Call Termination

Figure courtesy of Radvision Ltd

Application

Page 8: Larry Amiot Northwestern University amiot@northwestern

8

Session Description Protocol (SDP)

SDP is the protocol used to describe multimedia session announcement, multimedia session invitation and other forms of multimedia session initiation.

A multimedia session is defined, for these purposes, as a set of media streams that exist for a duration of time.

RFP 2327

Page 9: Larry Amiot Northwestern University amiot@northwestern

9Figure courtesy of Radvision Ltd

Call Redirection Using a Redirect Server

Page 10: Larry Amiot Northwestern University amiot@northwestern

10Figure courtesy of Radvision Ltd

Call Proxy Scenario

Page 11: Larry Amiot Northwestern University amiot@northwestern

11

Authentication- RFC 3261

Any time that a proxy server or UA receives a request, it MAY challenge the initiator of the request to provide assurance of its identity.

No authorization systems are recommended or discussed in this document.

The "Digest" authentication mechanism described in this section provides message authentication and replay protection only, without message integrity or confidentiality.

Basic should not be usedMicrosoft LCS supports Kerberos and NTLM

Page 12: Larry Amiot Northwestern University amiot@northwestern

12

A Few Multipoint SIP Implementation Examples

There is considerable point-to-point SIP-based videoconferencing going on

The following examples concentrate on multipoint videoconferencing

• Microsoft Live Communications Server• Wave3 Sessions• Radvision ViaIP

Page 13: Larry Amiot Northwestern University amiot@northwestern

13

Windows Messenger- The Microsoft Approach

Page 14: Larry Amiot Northwestern University amiot@northwestern

14

Windows Messenger

SIP-based Runs on Windows XP systems (sorry no

Macs) Core Features:

– Presence and contact list management– Instant Messaging– Voice and Video– Data collaboration and File transfer– PC to Phone– Administrative Policies to enable/disable features– Acoustic Echo Cancellation in software

Page 15: Larry Amiot Northwestern University amiot@northwestern

15

Windows Messenger

Microsoft .Net SIP server or enterprise SIP server

Can not go point-to-point using IP addressing- needs proxy server

Microsoft Live Communications Server (LCS) is their proxy server

Page 16: Larry Amiot Northwestern University amiot@northwestern

Internet

Windows Messenger Clients

Microsoft Live Communication

Server

SIP Point-to-Point Interoperability Using the Microsoft LCS

Microsoft Active Directory

Page 17: Larry Amiot Northwestern University amiot@northwestern

Radvision MCU

SIP

H.323

Internet

H.323 ClientsWindows Messenger

Clients

Microsoft Live Communication

Server

SIP/H.323 Interoperability Using the Radvision MCU

Microsoft Active Directory

Page 18: Larry Amiot Northwestern University amiot@northwestern

Radvision MCU

SIP

H.323

Internet

H.323 ClientsWindows Messenger

Clients

Microsoft Live Communication

Server

SIP/H.323 Interoperability Using the Radvision MCU

IMfirst

Microsoft Active Directory

Page 19: Larry Amiot Northwestern University amiot@northwestern
Page 20: Larry Amiot Northwestern University amiot@northwestern

20

Wave3’s Sessions SIP Client

Page 21: Larry Amiot Northwestern University amiot@northwestern

21

SessionsSip-basedWorks on/between PCs and

MACs IM, Audio/video, & data

sharingPoint-to-point using IP

addressing, or work with a SIP server

Wave3 has a server for multipoint video

WAVELETS codec Not compatible with

Windows Messenger data sharing

No echo cancellation

Session 3.0 beta• h.261 cif/qcif• h.263 cif/qcif• additional audio codecs

• Presence• IM• DTMF• Symmetric signaling and symmetric RTP to support NAT traversal solutions.

Page 22: Larry Amiot Northwestern University amiot@northwestern

Radvision MCU

SIP

H.323

Internet

H.323 ClientsSession Clients

Your Favorite SIP Server

SIP/H.323 Interoperability Using the Radvision MCU

Page 23: Larry Amiot Northwestern University amiot@northwestern

Radvision MCU

SIP

H.323

Internet

H.323 ClientsWave3 Session Clients

IPtel SIP Server

SIP Evaluation at Northwestern University

H.350 LDAP Server

Authentication

Not yet working

Page 24: Larry Amiot Northwestern University amiot@northwestern

24

A Few SIP Clients

Microsoft Windows MessengereCONF (Radvision resale)Wave3 Sessions (www.wave3software.com)

Network Convergence Laboratory at Claremont Graduate University (ncl.cug.edu)

Page 25: Larry Amiot Northwestern University amiot@northwestern

25

A Few SIP Proxy ServersMicrosoft Live Communications ServerHCL Technologies (www.hcltech.com) IndigoUbiquitySNOMVOCAL IptelDynamicSoftSiemensNorteleCONF

Page 26: Larry Amiot Northwestern University amiot@northwestern

26

Summary

SIP is an emerging TechnologyStaying with single a vender solution is currently workable

Interoperability between vender products is still in early stages

Multipoint conferencing is possibleData Sharing is still an interoperability problem

Selection of a SIP Proxy Server is critical as is its method of authentication