English: The diagram shows three entities. At start the phone is disconnected. A user tries to establish a connection. A connection request is sent to the switch and a timer is started.
An alternative deals with two possibles responses:
1 - The timer goes off because the switch did not reply and the phone goes back to the disconnected state.
2 - The switch grants the connection and the call is established.
to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.