/ SIMPLE : A control architecture for the wired and wireless Internet? Arup Acharya Network Systems Software Advanced Networking Services (On-Demand Innovation Services) IBM T J Watson Research Center sip:arup@research.ibm.com
What is (Session Initiation Protocol)? server (Overview) Session Initiation Protocol An Internet signaling protocol for setting up multimedia sessions signaling server server Mobility support call control in 3G networks o Terminal / service mobility Uses (overlay) control network of servers V RTP/UDP voice packets V independent of media type (voice, video) Media Path (RTP/UDP) decoupled from signaling Dynamic negotiation of device capabilities, media type Message routing is application specific o DNS-based name@domain addressing Dynamic resolution of URIs to device(s) o Location-based DNS enhancements for service records & ENUM VOIP Telephony & Voice Mail Unified Messaging Find-Me Me-Follow-Me Call Center Instant Messaging Collaboration Presence Push To Talk IMS (3G) Video IP TV Integration with Web-portals Client Desktop Devices s 2 Message syntax similar to HTTP SIMPLE : extensions to support Presence and IM Pub/Sub mechanism IM carried as signaling message payload Push-to-talk on cell-phones : an end-to-end control protocol not so far present in the Internet? Protocols & Technologies Network Real time media Real protocols time media (RTP) protocols And codecs (RTP) And codecs HTTP HTTP XML XML Registration Internet Protocol (IP) Subscription & Notifications /SIMPLE /SIMPLE Session Negotiation
IBM Global Services Widespread adoption of /SIMPLE Wireline providers [consumer/ business] - AT&T, MCI, Earthlink, [Vonage, Packet8,..] -Time Warner, Comcast - (Hosted) Covad, Verizon, Wireless providers -Sprint/Nextel, Verizon Wireless,.. [Push-to to-talk] talk] -3G (IMS) Web portals : Yahoo, MSN, AOL Service Providers : Webex Corporate Enterprise IT/networks Enterprise Software vendors -Microsoft, IBM, Oracle, BEA,. Networking vendors -Cisco, Nortel, Nokia, Lucent,. Emerging Infrastructure vendors -Sonus, NexTone, Antepo,.. -Open Source : Foundry Peer-to to-peer - Earthlink share - SOSIMPLE - Skype (proprietary) An Internet-wide overlay/control network is under construction? Gaming Consoles - Sony Playstation announced support for VoIP 3 Copyright IBM Corporation 2005
Impact of in the enterprise IT/ network infrastructure Enterprise communication now runs on a common infrastructure of servers and data network servers adjunct to web servers / directories Integrate web & applications on (a) client desktops and (b) servers Web browsers can be expected to recognise URIs Communication applications are desktop based : voice/video, presence, instant messaging Proxy Web server Conferencing IM Enablement HTTP Registrar Enterprise directory PSTN gateway Infrastructure Ethernet / 802.11 IP-PSTN Media gw IP Network (routers, switches..) 4
Demo scenario : Web page with clickable URIs Click here to call me ( recognised as a first-class protocol like HTTP or mailto without any change to browser code) 5
Impact of : server-based networking Telecom morphs to IT Circuit-Switched -based IP Communications M O N O L I T H I C Services & s Call Control integrated with switching hardware Voice Transport Services, s & Features (integration with business processes) APIs Session Control : servers APIs Common IP Network for both voice and data platforms (instead of dedicated switching PSTN hardware) Control (session, call) implemented as server application software 6
Role of in 3rd Generation mobile networks : IMS IP Multimedia subsystem (IMS) in 3GPP is based on Call/session control and roaming via client on cell-phones : SMS replaced by -based IM Call Session ControlFunction (CSCF) enabled devices Presence Push-to-talk IP Multimedia Core IM GPRS/EDGE/ WCDMA GGSN IP transport Any AS Service enablers/ applications 7 s
Messages : Header + Body Headers 8 Used for routing at servers Could be modified hop-by-hop Routing is application-specific Ok not to recognize a (new) field Message Body Could be XML / SDP / text/.. (e.g Presence Subscriptions) Not (required to be) interpreted hop-by-hop Captures best of both worlds? Efficiency of IP headers Flexibility of -layer messages IP Header UDP Header INVITE sip:gordon@ca.ibm.com /2.0 Via: /2.0/UDP sip-proxy.watson.ibm.com From: Arup Acharya <sip:arup@research.ibm.com> To: Gordon Kerr <sip:gordon@ca.ibm.com> Call-ID: c2943000-e0563-2a1ce-2e323931@9.2.91.243 CSeq: 1 INVITE Expires: 180 User-Agent: Cisco IP Phone/ Rev. 1/ enabled Accept: application/sdp Contact: sip:arup@9.2.91.243:5060 Content-Type: application/sdp Content-Length : 124 v=1 o=- V=- C=IN IP4 9.2.91.243 t=m=video 4004 RTP/AVP 13 26 a=rtpmap:14 MPA/90000 BODY HEADER
Possible impact on Internet-based services / architecture A new de-facto control layer based on -based networking Media server (control overlay) Interesting services are derived from this overlay network PSTN Media Sessions (voice, video,..) Instant messaging Presence Event Notification (pub/ sub) Naming/ addressing Location based Services Mobility Control -based Primitives / Base Services Registrar Proxy IM IM Presence Integration with DNS/ ENUM Session Border Control (firewalls) -based Convergence layer TCP/IP Network : Connectivity / Routing / Transport 9
Ongoing Research Project : Scaling servers is multi-faceted; thus, potentially multiple server performance bottlenecks Session Setup (voice/ video) Presence Rate of subscription / notification requests Registration server Registration Session setup proxy Redirect/ location server Updates in presence information, including non- sources SUBSCRIBE NOTIFY RTP/UDP packets (media) Collaboration, e.g. conferencing (Conference) Presence Information - registrar -Network login (e.g. 3G) -.. Instant Messaging Number of messages Size of messages Presence server Session setup Media mixer Instant Message IM RTP/UDP packets (media) 10 Joint work with E. Nahum, J.M. Tracey, Z.Y. Shae, X. Wang (IBM Research)
on Wearable Devices (Linux WatchPad) Linux WatchPad as a wearable control device Interface always visible/ easily accessible Receive phone calls on watch and decide how to respond Move an ongoing call from a PSTN phone to cell phone Receive IMs with yes/no responses Subscription notifications : display as icons Prototype completed, patent filed 11 Joint work with Wearable Computing Group (Stefan Berger, Chandra Narayanaswami)
Conclusions Adoption of across enterprise, service provider and mobile providers effectively creating an Internet-wide overlay control network s and software have a transformational role to play Shift from router-based networking to server-based networking Is this the next step in the architectural evolution of the Internet? THANK YOU! More information: Contact : Arup Acharya, IBM TJ Watson Research Ctr arup@us.ibm.com / +1 914 784 7481 http://www.research.ibm.com/people/a/arup 12 Further details on work in IBM Research: http://www.research.ibm.com/people/a/arup/custom2.html
Research Pilot + new components (application integration, conferencing service) Conference Manager control CONVEDIA conferencing hardware (IM, email, web,..) protocol Client Laptop +App service integration Proxy transfer phone PSTN phone RTP/UDP Voice packets (multi-party connection) Cisco 3640 gateway RTP/UDP Voice packets (point-point connection) Siemens PBX PSTN POTS phone 13