Developing A Sip User Agent Using The Jain Sip Stack.

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• Developing A Sip User Agent Using The Jain Sip
  Stack.
• Robert.V Masango
• Supervisors Alfredo Terzoli , Ming Hsieh

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Introduction (1)

• What Are User Agents In A
• Telecommunications Context ?
• These are Internet endpoints,that exchange
  information,in the form of video,text messages
  and voice .
  
  
  

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Introduction (2)

• What Is Sip ?
• - Sip stands for session initiation protocol
• - Based on a response-request paradigm,sip
• initiates sessions between users on the
  internet.

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What Are (Multimedia) Sessions?

• - From the Session Description Protocol
  specification "A multimedia session is a set of
  multimedia senders and receivers and the data
  streams flowing from senders to receivers.

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How Sip Works (1)

• A caller sends an INVITE request to a callee
  either
• 1) Via a proxy server.
• 2) Point -to -Point.

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How Sip Works (2)

• - After the session has been established
  audio,video and text messages are
  exchanged,depending on the agreement between the
  user agents.

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How Sip Works (3)
 
Model of the SIP environment
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Most Important Sip Methods

• - Invite
• - Ack
• - Bye
• - Cancel
• - Registers
• - Options

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Establishing Communication (1)

• - Registering,initiating and locating the user.
• - Determining the media to use.
• - Determining the willingness of the called party
  to communicate.
• - Setup the media streams.

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Establishing Communication(2)

• - Call modification or handling.
• - Call termination.

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What Im going to do?

• - Develop a user agent using the jain sip stack.
• - And if there is time develop a simple proxy
  server.

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Example Of An Invite Request (1)

• - INVITE sipRobert_at_cs.ru.ac.za
• - To sipRobert_at_cs.ru.ac.za
• - From sipMing_at_cs.ru.ac.za
• - Call-ID Rhodes_CompSci_at_10.0.0.1
• - CSeq 8 INVITE

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Example Of An Invite Request (2)

• - Content-Type application/new format
• ltaudiogt
• ltpcmu port"443"/gt
• lt/audiogt

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Example Of A Register Request

• - REGISTER cs.ru.ac.za SIP/2.0
• - To Robert_at_cs.ru.ac.za
• - From Robert_at_cs.ru.ac.za
• - Call-ID Fort_Hare_at_10.0.2.2
• - Contact Robert _at_cs.ru.ac.za
• - CSeq 8 REGISTER
• - Content-Length 0

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Resources Available (1)

• - http//www.ietf.org/rfc/rfc2543.txt
• - Papers from various Universities/Companies
  working with sip,including Rhodes.

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Resources Available (2)

• - The jain sip stack is open source and freely
  available.Its targeted towards telephony over
  networks.

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Expected Output

• A platform independent sip user agent.

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Questions

• Are There Any Questions?

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Thank You Very Much