SIP/ SIMPLE : A control architecture for the wired and wireless Internet?

(1)

SIP/ SIMPLE : A control architecture for the wired

and wireless Internet ?

Arup Acharya

Network Server Systems Software

Advanced Networking Services (On-Demand Innovation Services)

IBM T J Watson Research Center

(2)

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 signaling Dynamic negotiation of device capabilities, media type Message 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

What is SIP (Session Initiation Protocol) ?

(Overview)

SIP server SIP server

V V V V SIP server SIP signaling RTP/UDP voice packets Protocols & Technologies SIP/SIMPLE SIP/SIMPLE Subscription & Notifications Session Negotiation Registration

Real time media protocols (RTP)

And codecs

Real time media protocols (RTP) And codecs Push Push To To Talk Talk IMS (3G) IMS (3G) VOIP VOIP

Telephony & Voice Mail

Unified Messaging

Find

Find--MeMe--FollowFollow--MeMe Call Center Call Center HTTP XML HTTP XML Presence Presence Instant Instant Messaging Messaging Collaboration Collaboration Video Video IP TV IP TV Integration Integration with with Web

Web--portalsportals

Client Desktop Client Desktop Devices Devices Servers Servers

Internet Protocol (IP) Network

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3

IBM Global Services

Widespread adoption of SIP/SIMPLE

Wireline

providers [consumer/ business]

--

AT&T, MCI, Earthlink, [Vonage, Packet8, …

AT&T, MCI, Earthlink, [Vonage, Packet8,

…..]

..]

--

Time Warner, Comcast

--

(Hosted) Covad

(Hosted)

Covad,

, Verizon

Verizon,

,…

…

Wireless providers

--

Sprint/Nextel,

Sprint/Nextel, Verizon

Verizon

Wireless,..

[Push

[Push-

-to

to-

-talk]

talk]

--

3G (IMS)

Web portals : Yahoo, MSN, AOL

Application Service Providers :

Webex

Corporate Enterprise IT/networks

Enterprise Software vendors

--

Microsoft, IBM, Oracle, BEA,…

Microsoft, IBM, Oracle, BEA,

….

.

“

Networking

”

vendors

--

Cisco, Nortel, Nokia, Lucent,…

Cisco, Nortel, Nokia, Lucent,

….

.

Emerging Infrastructure

vendors

--

Sonus

, NexTone

,

NexTone,

, Antepo

Antepo,..

,..

--

Open Source : SIPFoundry

Open Source :

SIPFoundry

Peer

-

to

-

peer SIP

--

Earthlink SIPshare

Earthlink

SIPshare

--

SOSIMPLE

--

Skype

(proprietary)

Gaming Consoles

--

Sony Playstation

Sony

Playstation

announced

support for VoIP

An

In

ter

ne

t-w

ide

ov

er

lay

/co

nt

ro

l n

etw

or

k is

un

de

r c

on

str

uc

tio

n ?

(4)

Impact of SIP in the enterprise IT/ network infrastructure

Enterprise communication now runs on a common infrastructure of servers and data network

SIP servers adjunct to web servers / directories

Integrate web & SIP applications on (a) client desktops and (b) servers

►Web browsers can be expected to recognise SIP URIs

Communication applications are desktop based : voice/video, presence, instant messaging

IP Network (routers, switches..) Ethernet / 802.11

HTTP

Enterprise Enterprise directory directory Web Web server server IP-PSTN Media gw SIP Infrastructure SIP Infrastructure Proxy Proxy Conferencing Server PSTN PSTN gateway gateway Registrar Registrar

SIP

Application

Enablement

IM Server IM Server

(5)

5 Click here to call me (SIP recognised as a first-class protocol like HTTP or mailto without any change to browser code)

Demo scenario : Web page with

(6)

Impact of SIP : server

-

based networking

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 softwa

Control (session, call) implemented as server application softwa

re

M O N O L I T H I C

Circuit-Switched

SIP-based IP

Communications

Common IP Network for both

voice and data

Session Control : SIP servers

Services, Applications & Features

(integration with business

processes) processes) APIs APIs Call Control integrated with switching hardware Services & Applications Voice Transport

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7

Role of SIP in 3

rd

_{Generation mobile networks : IMS}

GPRS/EDGE/

WCDMA

Push-to-talk

SIP

GGSN

SIP enabled

devices

IM

Any SIP AS

Presence

IP transport

Application

Servers

Call Session

ControlFunction

(CSCF)

IP Multimedia Core

Service enablers/

applications

IP Multimedia subsystem (IMS) in 3GPP is based on SIP

Call/session control and roaming via SIP

(8)

SIP 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/2.0

Via: SIP/2.0/UDP sip-proxy.watson.ibm.com

From: Arup Acharya <sip:[email protected]> To: Gordon Kerr <sip:[email protected]>

Call-ID: [email protected] CSeq: 1 INVITE

Expires: 180

User-Agent: Cisco IP Phone/ Rev. 1/ SIP enabled Accept: application/sdp Contact: sip:[email protected]: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

SIP BODY

SIP HEADER

UDP Header IP Header

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9

Possible impact on Internet

-based services / architecture

-

based services / architecture

A new de-facto control layer

based on SIP

Server-based networking

“Interesting” services are derived

from this overlay network

Location Location based based Services Services SIP SIP Media Media PSTN SIP server SIP server (control overlay) (control overlay)

TCP/IP Network : Connectivity / Routing / Transport

Registrar

Server

Server Proxy ServerProxy Server

Presence Presence Server Server Integration Integration with with DNS/ ENUM DNS/ ENUM SIP

SIP--based Convergence layerbased Convergence layer Media Sessions Media Sessions (voice, video,..) (voice, video,..) Session Session Border Border Control Control (firewalls) (firewalls) Instant Instant messaging

messaging PresencePresence Event NotificationEvent Notification(pub/ sub)(pub/ sub) Naming/Naming/ addressing addressing

IM Server SIP

SIP--based Primitives / Base Servicesbased Primitives / Base Services

IM IM Server Server Mobility Mobility Control Control

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Ongoing 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 proxy SIP proxy Session Session setup setup RTP/UDP packets (media) Application Server Redirect/ location server Registration server Registration Registration Session Session setup setup RTP/UDP packets (media) Application (Conference) Server Media

mixer InstantInstant Message Message

Presence server

SUBSCRIBE

SUBSCRIBE NOTIFYNOTIFY Presence Information -SIP registrar -Network login (e.g. 3G) - .. IM Server

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SIP on Wearable Devices (Linux

WatchPad)

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

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Conclusions

Adoption 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 7481

http://www.research.ibm.com/people/a/arup

Further details on SIP work in IBM Research:

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13

Research SIP Pilot + new components (application integration,

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 connection connection))

SIP

control

CONVEDIA

conferencing

hardware

SIP Conference

Manager

Client Laptop

SIP

service

transfer

SIP

SIP+App

integration

Application

protocol

Application

Server (IM,

email, web,..)

PSTN phone

RTP/UDP RTP/UDP Voice packets Voice packets (point

(point--point point connection) connection)

SIP/ SIMPLE : A control architecture for the wired and wireless Internet?