SIP/ SIMPLE : A control architecture for the wired SIP/ SIMPLE : A control architecture for the wired and wireless Internet ?and wireless Internet ?
Arup AcharyaNetwork Server Systems Software Advanced Networking Services (On-Demand Innovation Services)IBM T J Watson Research Center
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Session Initiation Protocol• An Internet signaling protocol for setting up multimedia sessions
Mobility support – call control in 3G networks
o Terminal / service mobility
• Uses (overlay) control network of SIP servers independent of media type (voice, video)Media Path (RTP/UDP) decoupled from signalingDynamic negotiation of device capabilities, media typeMessage routing is application specific
o DNS-based
• name@domain addressing Dynamic resolution of SIP URIs to device(s)
o Location-based DNS enhancements for SIP service records & ENUM
• Message syntax similar to HTTP
SIMPLE : SIP extensions to support Presence and IM• Pub/Sub mechanism
• IM carried as signaling message payload Push-to-talk on cell-phones
SIP : an end-to-end control protocol not so far present in the Internet ?
What is SIP (Session Initiation Protocol) ? (Overview) SIP server SIP server
V V V V
SIP server
SIP signaling
RTP/UDP voice packets
Protocols&
TechnologiesSIP/SIMPLE
SIP/SIMPLE
Subscription &Notifications
SessionNegotiationRegistrationReal time media
protocols (RTP)And codecs
Real time media protocols (RTP)
And codecs
PushPushToTo
TalkTalk
IMS (3G)IMS (3G)
VOIPVOIPTelephony & Voice MailTelephony & Voice Mail
Unified MessagingUnified MessagingFindFind--MeMe--FollowFollow--MeMe
Call CenterCall Center
HTTP
XMLHTTP
XML
PresencePresenceInstantInstant
MessagingMessaging
CollaborationCollaboration
VideoVideo
IP TVIP TV
IntegrationIntegrationwithwith
WebWeb--portalsportalsClient DesktopClient Desktop
DevicesDevicesServersServers
Internet Protocol (IP)
Network
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IBM Global Services
© Copyright IBM Corporation 2005
Widespread adoption of SIP/SIMPLE
WirelineWireline providers [consumer/ business]providers [consumer/ business]-- AT&T, MCI, Earthlink, [Vonage, Packet8, AT&T, MCI, Earthlink, [Vonage, Packet8, ……..]..]--Time Warner, Comcast Time Warner, Comcast -- (Hosted) (Hosted) CovadCovad, , VerizonVerizon,,……
Wireless providersWireless providers--Sprint/Nextel, Sprint/Nextel, VerizonVerizon Wireless,..Wireless,..[Push[Push--toto--talk]talk]--3G (IMS)3G (IMS)
Web portals : Yahoo, MSN, AOLWeb portals : Yahoo, MSN, AOL
Application Service Providers : Application Service Providers : WebexWebex
Corporate Enterprise IT/networksCorporate Enterprise IT/networks
Enterprise Software vendorsEnterprise Software vendors--Microsoft, IBM, Oracle, BEA,Microsoft, IBM, Oracle, BEA,……..
““NetworkingNetworking”” vendorsvendors--Cisco, Nortel, Nokia, Lucent,Cisco, Nortel, Nokia, Lucent,……..
Emerging Infrastructure Emerging Infrastructure vendorsvendors
--SonusSonus, , NexToneNexTone, , AntepoAntepo,..,..--Open Source : Open Source : SIPFoundrySIPFoundry
PeerPeer--toto--peer SIPpeer SIP-- Earthlink Earthlink SIPshareSIPshare-- SOSIMPLESOSIMPLE-- SkypeSkype (proprietary)(proprietary)
Gaming ConsolesGaming Consoles-- Sony Sony PlaystationPlaystation announced announced support for VoIPsupport for VoIP
An Internet-wide overlay/control network is
under construction ?
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Impact of SIP in the enterprise IT/ network infrastructureImpact of SIP in the enterprise IT/ network infrastructureEnterprise communication now runs on a common infrastructure of servers and data networkSIP servers adjunct to web servers / directoriesIntegrate web & SIP applications on (a) client desktops and (b) servers
►Web browsers can be expected to recognise SIP URIsCommunication applications are desktop based : voice/video, presence, instant messaging
IP Network (routers, switches..)
Ethernet / 802.11
HTTPHTTP
EnterpriseEnterprisedirectorydirectory
Web Web serverserver
IP-PSTNMedia gw
SIP InfrastructureSIP Infrastructure
ProxyProxyConferencingServer
PSTNPSTNgatewaygateway
RegistrarRegistrar
SIPSIP
Application
Enablement
IM ServerIM Server
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Click hereto call me
(SIP recognised as a first-class protocol like HTTP or mailtowithout any change to browser code)
Demo scenario : Web page with Demo scenario : Web page with ‘‘clickableclickable’’ SIP SIP URIsURIs
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Impact of SIP : serverImpact of SIP : server--based networkingbased networkingTelecom morphs to IT Telecom morphs to IT
►► Server platforms (instead of dedicated switching PSTN hardware)Server platforms (instead of dedicated switching PSTN hardware)►► Control (session, call) implemented as server application softwaControl (session, call) implemented as server application softwarere
MONOLITHIC
Circuit-Switched SIP-based IP Communications
Common IP Network for both Common IP Network for both voice and datavoice and data
Session Control : SIP serversSession Control : SIP servers
Services, Applications & FeaturesServices, Applications & Features(integration with business (integration with business
processes)processes)
APIs
APIs
Call Control integrated with
switchinghardware
Services & Applications
VoiceTransport
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Role of SIP in 3Role of SIP in 3rdrd Generation mobile networks : IMSGeneration mobile networks : IMS
GPRS/EDGE/GPRS/EDGE/WCDMAWCDMA
Push-to-talkSIP
GGSN
SIP enableddevices
IM
Any SIP AS
Presence
IP transport
ApplicationServers
Call SessionControlFunction
(CSCF)
IP Multimedia Core
Service enablers/applications
IP Multimedia subsystem (IMS) in 3GPP is based on SIP
Call/session control and roaming via SIP
SIP client on cell-phones : SMS replaced by SIP-based IM
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SIP Messages : Header + BodySIP Messages : Header + Body►SIP Headers
– Used for routing at SIP 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 Application-layer
messages
INVITE sip:[email protected] SIP/2.0Via: SIP/2.0/UDP sip-proxy.watson.ibm.comFrom: Arup Acharya <sip:[email protected]>To: Gordon Kerr <sip:[email protected]>Call-ID: [email protected]: 1 INVITEExpires: 180User-Agent: Cisco IP Phone/ Rev. 1/ SIP enabledAccept: application/sdpContact: sip:[email protected]:5060Content-Type: application/sdpContent-Length : 124
v=1o=-V=-C=IN IP4 9.2.91.243t=-m=video 4004 RTP/AVP 13 26a=rtpmap:14 MPA/90000
SIP BO
DY
SIP HEA
DER
UDP Header
IP Header
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Possible impact on InternetPossible impact on Internet--based services / architecturebased services / architecture
A new de-facto control layer based on SIP
Server-based networking
“Interesting” services are derived from this overlay network
Location Location basedbasedServicesServices
SIP SIP
MediaMedia
PSTN
SIP serverSIP server(control overlay)(control overlay)
TCP/IP Network : Connectivity / Routing / Transport TCP/IP Network : Connectivity / Routing / Transport
Registrar Registrar ServerServer
Proxy Proxy ServerServer
PresencePresenceServerServer
IntegrationIntegrationwithwithDNS/ ENUMDNS/ ENUM
SIPSIP--based Convergence layerbased Convergence layer
Media SessionsMedia Sessions(voice, video,..)(voice, video,..)
Session Session Border Border ControlControl(firewalls)(firewalls)
InstantInstantmessagingmessaging PresencePresence Event NotificationEvent Notification
(pub/ sub)(pub/ sub) Naming/Naming/addressingaddressing
IMServer
SIPSIP--based Primitives / Base Servicesbased Primitives / Base Services
IMIMServerServer
MobilityMobilityControlControl
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Ongoing Research Project : Scaling SIP serversOngoing Research Project : Scaling SIP servers
Session Setup (voice/ video)
Collaboration, e.g. conferencing
Presence►Rate of subscription / notification requests
►Updates in presence information, including non-SIP sources
Instant Messaging►Number of messages
►Size of messages
SIP proxySIP proxy
SessionSessionsetup setup
RTP/UDP packets (media)
ApplicationServer
Redirect/ location server
Registrationserver
RegistrationRegistration
SessionSessionsetup setup
RTP/UDP packets (media)
Application(Conference)
Server
Mediamixer InstantInstant
Message Message
Presence server
SUBSCRIBESUBSCRIBENOTIFYNOTIFY
PresenceInformation
-SIP registrar-Network login(e.g. 3G)- ..
IM Server
SIP is multi-faceted; thus, potentially multiple server performance bottlenecks
Joint work with E. Nahum, J.M. Tracey, Z.Y. Shae, X. Wang (IBM Research)
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SIP on Wearable Devices (Linux SIP on Wearable Devices (Linux WatchPadWatchPad))
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
Joint work with Wearable Computing Group (Stefan Berger, Chandra Narayanaswami)
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ConclusionsConclusionsAdoption of SIP across enterprise, service provider and mobile providers effectively creating an Internet-wide overlay control network
Servers 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
[email protected] / +1 914 784 7481http://www.research.ibm.com/people/a/arup
Further details on SIP work in IBM Research:http://www.research.ibm.com/people/a/arup/custom2.html
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Research SIP Pilot + new components (application integration, Research SIP Pilot + new components (application integration, conferencing service)conferencing service)
Cisco 3640 SIP gateway Siemens
PBX
PSTN
POTS phone
SIP phone
SIP Proxy Server
RTP/UDP RTP/UDP Voice packets Voice packets ((multimulti--party party connectionconnection))
SIPSIP
controlcontrol
CONVEDIA CONVEDIA conferencing conferencing hardwarehardware
SIP ConferenceManager
Client Laptop
SIP SIP serviceservice
transfer
SIPSIP
SIP+AppSIP+Appintegrationintegration
Application
Application protocol
Application Server (IM,
email, web,..)
PSTN phone
RTP/UDP RTP/UDP Voice packets Voice packets (point(point--point point connection)connection)
SIPSIP
