Behavior of each interface

bool createCall(callerNum,calleeNum)

1.Description

• This is the normal message from client to our system
• Input arguments are the destination of telephone numbers.

2. Behavior

• After calling, our system will proceed to set up the call between a Caller and a Callee (setupCall interface and sendVoice) with destination number sequentially.
• The result of this interface is responded as return value after call setup scenario (1 -> 2 -> 3 -> 4 -> 5)
• Even if sever is crashed during the call setup transaction, the transaction should be completed successfully.

3. Exception case

• Received destNums are wrong.
• A Caller or a Callee can be busy.
• When a user is busy (a Caller or a Callee)

bool setupCall(destNum)

1.Description

• This is the normal message from client to our system
• Input arguments are the destination of telephone numbers.

2. Behavior

• After receiving createCall() from Client, our system proceeds to set up the call to a Caller and a Callee sequentially with the destNum. The setupCall() to a Callee is initiated after receiving successful return value from the a Caller.
• The return value responded to server after successful call setup scenario (2 -> 3)

3. Exception case

• Received destNums are wrong.

bool sendVoice(message)

1.Description

• This is the normal message from a Caller to a Callee or a Callee to a Caller to transfer voice to the opposite side.
• An input argument is the user data, voice.

2. Behavior

• After receiving createCall() from Client, Our system proceeds to set up the call to a Caller and a Callee sequentially. The setupCall() to a Callee is initiated after receiving successful return value from the caller.
• The return value responded to initiator after receiving the voice successfully.

3. Exception case

• None

bool ordReleaseCall(destNum)

1.Description

• This is the normal message from Caller or Callee to Server system when caller or callee releases the call after calling.
• An input argument is the destination telephone number.

2. Behavior

• After successful calling, a Caller or a Callee can request to release the call to the Server through this method.
• The return value will be responded to initiator.

3. Exception case

• Received destNums are wrong.

bool askReleaseCall()

1.Description

• This is the normal message from Server to a Caller or a Callee to release the pending call.
• There is no input argument.

2. Behavior

• After receiving releaseCall1() from a Caller or a Callee, server proceeds to request to release the related call to other side with the destNum.
• The return value responded to Server after releasing the pending call.

3. Exception case

• None