1. SIP – A look under the hood OR “What’s the best way to make my cutting edge product?” Jacob Bridger VP Marketing, TBU October, 14 th 2003

2. “So you want to build a product that happens to support SIP”

3. SIP D evelopment C hallenges–Complexity TCP/IP, OS SIP TransportSIP Message Transaction Dialog, Registration, User Agent Behavior Proxy/Reg Application (Features, services, UI …) SIP Extensions SIP is No Longer a Simple Protocol… Location DB Registration Spirals Loops REFER SIP-T… PRACK INFO SUBSCRIBE NOTIFY 3GPP others… REFER SIP-T… PRACK INFO State Machine Authentication REFER Record Routing re-INVITE Loose Routing State Machine Mapping fragmentation SCTP IPv6 Conn Mgmt SCTP DNS UDP TCP Whitespaces Multipart MIME compact form SDP Encoding Parsing MIME ID Mapping branch CANCEL Timers State Machine UDP Reliability Authentication 100Rel

4. Evolving SIP Standard  Inconsistencies in REFER  Changes in retransmission timers  Changes in CANCEL  Response code for INVITE inside INVITE has changed  MaxForward has become mandatory  Transaction key identifier rules was changed  CallLeg identifier was changed  Prefix added to Via Branch  LR was added to Route for Loose Routing support  CANCEL became invalid for general transactions The Evolving Baseline SIP RFC 2543 Established –Aug 99 bis 00 – July 00 bis 00 – Aug 00 bis 01 – Aug 00 bis 02 – Sept 00 bis 02 – Nov 00 bis 03 – May 01 bis 04 – July 01 bis 05 – Oct 01 bis 06 – Jan 02 bis 07 – Feb 02 bis 09 – Feb 02 RFC3261 – June 02 Additionally hundreds of Drafts that constantly change New Changes Are Not Always Backwards Compatible Developers Need to Ensure Their Products Comply With New Version of Standard

5. A Family of SIP Development Solutions SIP Server Toolkit IP Phone Toolkit SIP Toolkit SIP Development Solutions ProLab TM Test Management Suite

6. Development Solutions A Family of SIP Development Solutions SIP Server Toolkit IP Phone Toolkit SIP Toolkit ProLab TM Test Management Suite SIP SIP Toolkit For development of GWs, Softswitches, IP Phones, Cellular phones, PDAs, Presence and IM clients and any type of User Agent

7. A Family of SIP Development Solutions SIP Server Toolkit IP Phone Toolkit SIP Toolkit SIP Development Solutions ProLab TM Test Management Suite SIP Server Toolkit  Proxy Server  Registrar Server  Redirect Server  B2BUA & Presence (coming version)

8. A Family of SIP Development Solutions SIP Server Toolkit IP Phone Toolkit SIP Toolkit SIP Development Solutions ProLab TM Test Management Suite IP Phone Toolkit  Framework for developing IP phones/residential GW  DSP integration

9. A Family of SIP Development Solutions SIP Server Toolkit IP Phone Toolkit SIP Toolkit SIP Development Solutions ProLab TM Test Management Suite ProLab TM Test Management Suite  Automated, script- driven testing (signaling and media)  Can simulate different network topologies

10. A Family of SIP Development Solutions SIP Server Toolkit IP Phone Toolkit SIP Toolkit SIP Development Solutions ProLab TM Test Management Suite

11. SIP Toolkit

12. Toolkit Applications  Enables development of all kinds of SIP applications: High density, high performance servers Medium, enterprise scale applications Terminals (including compact embedded devices)  Softswitches  Gateways  SIP Servers – Proxy, Redirect, Registrar  Application Servers  Conference Bridges  Load Balancers  SIP FW/NAT solutions  IP Phones  Soft Phones  2.5-3G Cellular Phones  Connected PDAs  Multimedia Terminals

13. TCP/IP, OS SIP TransportSIP Message Transaction Dialog, Registration, User Agent Behavior Proxy/Reg Application (Features, services, UI …) SIP Extensions SIP Tool Layering Model Application code STANDARD: RFC 3261 (SIP) SIP Extensions RFC 2327 (SDP) Platform 3 rd Party

14. SIP Toolkit Architecture OS/Network OS abstraction layer (core) RTP/RTCP Application SIPSDP  RFC 3261 (SIP) Compliant  Baseline protocol functionality + extensions  Full RFC 2327 (SDP)Support  Parser and Encoder  Comparison Functions  RFC 1889/1890 Compliant  RTCP reports  Standalone, replaceable module  Allows for enhanced portability  Keeps rest of the Toolkit OS agnostic

15. SIP Server Toolkit

16.  A typical SIP Server application has 3 parts: SIP Server Development Challenges  SIP stack standard  SIP Server core engine standard Proxy Registrar Redirect B2BUA Presence  Application implementation-specific

17. Media Server Example: Load Balancing SIP Server (B2BUA) SIP Media Server Farm SIP SIP Server IP Network

18. Media Server Load Balancing SIP Server IP Network (B2BUA) SIP Media Server Farm SIP SIP Server

19. Media Server Load Balancing SIP Server IP Network (B2BUA) SIP Media Server Farm SIP Server SIP

20. Load Balancing SIP Server B2BUA Presence Server SIP Server High-Level Proxy Core SIP Stack SIP Server Manager SIP Server Low- Level Load Balancing Application Presence Agent Location DB Security SIP Server Toolkit

21. Call Proxying Using Location DB Location DB SIP Server Toolkit OS/Network Application Location DB Server Components LDAP_Lookup (bob) Proxy Core Object Event (REQ_RCVD) Proxy() Policy INVITE bob@example.com INVITE bob@acme.com Lookup (bob) Bob@acme.com

22. SIP IP Phone/IAD Toolkit

23. IP Phone/IAD Toolkit Architecture Customer SuppliedAdditional RTP/RTCP Toolkit Operating System Configuration and Initialization Integration Layer DSP Services Telephony Services OS Abstraction Layer RTP/RTCP Toolkit Media Device Manager (MDM) API SIP Stack H.323 Stack Megaco Stack MGCP Stack SIP Call Control H.323 Call Control Call Control Managers MEGACO Termination Manager MGCP Endpoint Manager Media Control Managers RADVISION Standards Implementation Media Device Manager (MDM) API OS Abstraction Layer RTP/RTCP Toolkit SIP Call Control H.323 Call Control Call Control Managers MEGACO Termination Manager MGCP Endpoint Manager Media Control Managers SIP Stack H.323 Stack MEGACO Stack MGCP Stack

24. General Features  Initiate Basic Call  Receive Basic Call  Multiple Line Appearances  Caller ID  Hold  Transfer  (3-way) Conference  In-call DTMF relay  Customizable Man/Machine Interfaces to allow developers to precisely define their own look and feel

25. SIP Testing & Validation

26. ProLab VoIP Testing Environment IP H.323 Test Agent RTP Testing Device Under Test Gatekeeper H.323 Device Under Test SIP Test Agent SIP Server Agent RTP Testing SIP Test Management Test Scheduling Tester

27. Summary  Engineering resources are constrained  Re-inventing the IETF wheel makes little sense  Advanced tools exist today  SIP Stack  SIP Server  SIP IP Phone/IAD  SIP Testing (ProLab)  Focus should be on features, application, innovation, differentiation  Focus should be on what benefits the customers, not the “cool” technology beneath

28. www.radvision.com jacob@radvision.com Thank-You