IBM Z9, Planning Manual

Page: 80 / 274

ESCON CTC Configurations: Figure 2-11 shows how shared ESCON channels
can reduce the ESCON channel requirements for ESCON CTC configurations. In
this example, the CPC requires CTC communications among all its LPs.
By using two shared ESCON CTC/CNC pairs (4 shared ESCON channels), you
can:
v Replace five unshared ESCON CTC/CNC pairs (10 unshared ESCON channels)
and the ESCD used to connect them
v
Provide full redundancy
I/O connectivity is maintained while hardware requirements (channels and an
ESCD) are reduced.
LP1
LP1
C
C
T
T
C
C
C
C
T
T
C
C
C
T
C C
T
C C
T
C C
C
N
N
C
C
C
C
N
N
C
C
C
N
C C
N
C C
N
C
LP2
LP2
LP3
LP3
LP4
LP4
LP5 LP5
Without shared
ESCON channels
With shared
ESCON channels
Two channel pairs (CTC to CNC)
provide redundancy to enhance
availability.
Similar channel savings can be
achieved with multiple MIF
processors.
LP5
ESCD
LPAR
Figure 2-11. Consolidating ESCON Channels Used for ESCON CTC Communications
2-26
PR/SM Planning Guide