Let us consider the following Web services: 1. WS1: with messages M11 (input), M12 (output), and M13 (output) 2. WS2: with messages M21 (input), M22 (output), and M23 (output) 3. WS3: with messages M31 (input), M32 (output), and M33 (output 4. WS4: messages M41 (input) and M42 (output) and M45 (output) 5. WS5: with messages M51 (input), M52 (output), and M53 (output) 6. WS6: with messages M61 (input), M62 (output), and M63 (output)

The invocation of the services is done according to the following coordination protocol: The first service to be invoked is WS1, WS2, or WS3. If WS2 returns M22, then the client should invoke WS4. Otherwise it should invoke WS5. If WS1 returns M12, then the client should invoke WS4. Otherwise it should invoke WS3. After invoking WS3 the client invokes WS5. After invoking WS4, the client invokes WS5. After invoking WS5, if the returned message is M52 then the client invokes WS6 then terminates. If the returned message is M53 then the client invokes WS2. After invoking WS6, if the returned message is M62 then the client invokes WS3. If the returned message is M63 then the client terminates.

1) Give the state diagram depicting the coordination protocol.

2) Give one example of valid conversation.

3)Give one example of invalid conversation