ESCON CTC with shared channels

A fully redundant any-to-any CTC configuration consists of two sets of CTC minimum configurations, each associated with a separate ESCON Director. CTC communication workload between System A and System B is balanced between four CTC connections. All the channel paths are shared. See Figure 1. For recommendations for numbering CTC control units and devices to simplify CTC configurations, see the ESCON and FICON Channel-to-Channel Reference, SB10-7034.
Note: All shared CTC examples within a single CPC exclude an LP from communicating with itself. This exclusion is required for some subsystems (for example, XCF). Other subsystems might not have this restriction and might support the communication of an LP with itself.
Figure 1. ESCON CTC with shared channels
this graphic displays the ESCON CTC with shared channels