Simplified Internet Phone System

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Simplified Internet Phone System

• Prepared by Dr. Tony K. C. Chan.

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Learning Objectives

• Simplified Internet phone system
• Signaling protocol
• State diagram
• Programming design

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1. Overview
Standby
Calling
Chatting
Standby
Standby
Ringing
Connecting
Chatting
Disconnecting
Standby
INVITE 4000
Your media port 4000
Your media port 5000
RINGING
OK 5000
10.10.10.1
ACK
Media Channel
BYE
I want to call user B.
OK
I accept the call.
I want to terminate the call.
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2. Transition of Phone State

• Six states
• Standby (User, INVITE)
• Calling (RINGING, OK)
• Ringing (User)
• Connecting (ACK)
• Chatting (User)
• Disconnecting (OK)

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3. Programming Design
Send receive messages
Implement the GUI
Store the target Info.
Core object
Play ringing sound
Setting up media Communication.
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Exercise 1.1
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Solution
receiveCall
inviteCall
Calling
Ringing
startChatting
acceptCall
Calling
Ringing
startChatting
Chatting
Connecting
disconnectCall
disconnectCall
Chatting
Chatting
Standby
Disconnecting
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THE END