Cascaded Configuration, Two Switches; Cascaded Configuration, Three Switches - HP A7533A - Brocade 4Gb SAN Switch Base Administrator's Manual

there are only 2 domains in a path from a FICON Channel interface to a FICON Control Unit interface.
Channel
A
Figure 56

Cascaded configuration, two switches

Channel
A
Figure 57

Cascaded configuration, three switches

428 FICON fabrics
Switch Switch
Domain ID = 21 Domain ID = 22
Switch Switch
Domain ID = 21 Domain ID = 22
Switch
Domain ID = 23
Control
Unit
B
Control
Unit
C
Control
Unit
D