A Gateway For SIP Event Interworking

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A Gateway For SIP Event Interworking
- Sasu Tarkoma Thalainayar
Balasubramanian Ramya
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MOTIVATION

• Interworking of SIP event framework with the
  generic
• publish/subscribe system

Challenges

• SIP Event Framework does not support anonymous
  
• one-to-many event dissemination

• SIP Event Framework does not support
  expressive
• filtering

Proposed Solution

• Implementation of a gateway component enabling
  
• interworking between the SIP event framework,
  and
• publish/subscribe system

Application of the proposed Gateway

• Universal Data Access

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BACKGROUND INFORMATION
Session Initiation Protocol (SIP) a standard,
text-based, application layer, signaling
protocol developed by the Internet Engineering
Task Force (IETF). Described in RFC 3261
Purpose of SIP To establish, modify and
terminate multimedia sessions over the IP network
Acceptance as standard Selected by the 3rd
Generation Partnership Project (3GPP), as the
session establishment protocol for the 3GPP IP
Multimedia Core Network Subsystem (IMS)
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BACKGROUND INFORMATION
SIP Application Areas

• Internet Telephony

• Control Applications

• E-Commerce

• Multimedia Conferences

• Instant Messaging

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SIP EVENT FRAMEWORK
SIP Event Framework An extension of Session
Initiation Protocol, described in RFC 3265
Methods supported SUBSCRIBE, NOTIFY
SUBSCRIBER
NOTIFIER
Fig 1. SIP Event Subscription and Notification
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SIP DOMAIN
Fig 2. Working of SIP Domain
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COMPONENTS IN SIP DOMAIN
SIP Proxy Receives SIP requests/responses from
clients/ proxies, processes, and forwards
it to the next hop or final destination
SIP Client Receives/Sends SIP requests/responses
Registrar Maintains registered clients
information, queries and gets recent updates
from Location Server
Redirect Server (Redirect Mode) Provides the
contacted clients current address to the
contacting client
Location Server Stores updated client
information
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APPLICATION AREAS OF CONTENT BASED PUB/SUB
EVENT MODEL

• Active Badge Systems

• Proximity Sensors

• Information and Multimedia Delivery Services

• Positioning Systems

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WORKING OF PUBLISH/SUBSCRIBE EVENT MODEL
Publishers
Consumers
Event Service
Fig 3. Publish/Subscribe Event model
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GATEWAY DESIGN
Conversion, Mapping, State
Fig 4. Gateway Design
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IMPLEMENTATION ARCHITECTURE
subscribe/ notify
subscribe/ publish
Fig 5. Implementation Architecture
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GATEWAY FUNCTIONALITIES

• Receive SIP messages (requests/responses)

• Convert SIP message to pub/sub messages. Forward
  the
• converted messages to Fuego domain

• Receive pub/sub messages

• Convert pub/sub messages to SIP messages
  (requests/
• responses). Forward the converted messages to
  the
• SIP domain

• Associate the received messages using unique
  identifiers.
• Call Identifier of the SIP and subscription
  identifier of the
• Fuego message are used for association.

• Generate and send SIP provisional responses to
  the SIP
• domain

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SIP AND FUEGO SUBSCRIPTIONS/NOTIFICATIONS
Fig 6. SIP SUBSCRIBE and Fuego PUBLISH
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SIP AND FUEGO SUBSCRIPTIONS/NOTIFICATIONS
Fig 7. FUEGO SUBSCRIBE and SIP NOTIFY
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MOBILITY IN THE INTERWORKING ARCHITECTURE

• Intradomain mobility
• Intradomain terminal mobility is possible in
  both the SIP and
• Fuego domains
• Disconnected operation should be supported for
  user
• mobility

• Interdomain mobility
• Need buffering of messages at the gateway
• Roaming clients can send a signal to the
  gateway informing
• their location update, and get the buffered
  messages

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ADVANTAGES OF THE GATEWAY COMPONENT
Advantages
No modifications in the API of the interworked
domains
Supports extensibe implementation
Transparent architecture
Experimentatal observation

• Performed scalability and performance test for
  the gateway

• Used the presence event package

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Conclusion

• Under heterogenous environments interworking of
  different
• event standards is essential

Future Work

• Enhancing gateway functionality by providing
  filtering
• support, and load balancing

• Investigate the possibilities to provide
  various mobility support
• such as session mobility

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REFERENCES

• Java APIs for Integrated Network (JAIN)
  Session
• Initiation Protocol (SIP) API
• http//www.jcp.org/aboutJava/communityprocess/f
  inal/jsr032/

• National Institute of Standards and Technology
  (NIST)
• SIP (Session Initiation Protocol) Stack and
  Proxy
• http//snad.ncsl.nist.gov/proj/iptel/

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QUESTIONS ?
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THANK YOU !