-[[!if test="enabled(mscgen)" then="""
-And here's the resulting graph.
-
-[[!msc src="""
- arcgradient = 8;
-
- a [label="Client"],b [label="Server"];
-
- a=>b [label="data1"];
- a-xb [label="data2"];
- a=>b [label="data3"];
- a<=b [label="ack1, nack2"];
- a=>b [label="data2", arcskip="1"];
- |||;
- a<=b [label="ack3"];
- |||;
-"""]]