Message Sequence Chart

A message sequence chart ( MSC, Eng. Message Sequence Chart) is used (eg in support of the modeling with SDL) to represent uniformly exemplary message sequences between communicating objects.

MSC is a standard of the ITU -T, the telecommunication standardization sector of the International Telecommunication Union and recognizes two forms of representation: textual and graphical MSC MSC.

When using the Unified Modeling Language, the sequence diagram fulfills the role of the MSC.

Standards

• Z.120: Message Sequence Chart (MSC )
• Z.121: Specification and Description Language (SDL ) databinding to Message Sequence Charts (MSC )

Example

An MSC that represents a connection between the client and server can be specified in MSC / PR as follows:

Msc ExampleMSC;    inst client, server;    Idle condition shared all;      Instance client;        env in ConReq from;        out connect to server;      endinstance;      Server instance;        supplied to connect from client;        out conInd to env;      endinstance;    condition Connecting shared all;      Instance client;        in accepted from server;        out conCnf to env;      endinstance;      Server instance;        in conAcc from env;        out accepted to client;      endinstance;    condition Connected shared all; endmsc; Significantly more frequently than MSC / PR but you meet the more comprehensible MSC / GR, the graphical expression of MSC on. The above example scenario would see in MSC / GR as follows: