CE LR Coupling Express LR z14/z13/z13s to  z14/z13/z13s 10 Gbps 10 km unrepeated (6.2 miles) 100 km repeated (62 miles) 64 ICA SR Integrated Coupling  Adapter z14/z13/z13s to  z14/z13/z13s 8 GBps 150 meters  (492 feet) 80 IC Integrated Coupling  Adapter Internal communication Internal  speeds N/A 40 Type Description Use for connecting Link rate Distance z14  maximum  number of  ports a. 12x IFB3 protocol supports a maximum of four CHPIDs and connects to the other HCA3-O port. When connected  to a HCA2-O port, 12x IFB protocol is used. The protocol is auto-configured when conditions are met for IFB3.  The maximum number of combined external coupling links (active CE LR, ICA SR links, and  IFB LR) is 144 per IBM z14™ server. IBM z14™ servers support up to 256 coupling CHPIDs  per CPC. A z14 coupling link support summary for z14 is shown in Figure 4-6. For more information, see 4.5.3, “HCA3- O (12x IFB) fanout (FC 0171)” on page 156. When defining IFB coupling links (CHPID type CIB), HCD defaults to seven subchannels. A  total of 32 subchannels are supported on only HCA2-O LR (1xIFB) and HCA3-O LR (1xIFB)  on zEC12 and later when both sides of the connection use IFB protocol. Sysplex Coupling and Timing Connectivity:  IBM z14 M0x (M/T 3906) supports N-2  sysplex connectivity (z14M0x, z14 ZR1, z13, z13s, zEC12, and zBC12),  while IBM z14  ZR1 supports only N-1 sysplex connectivity  (z14 M0x, z14 ZR1, z134, and z13s). In a Parallel Sysplex configuration, z/OS and CF images can run on the same or on separate  servers. There must be at least one CF that is connected to all z/OS images, even though  other CFs can be connected only to selected z/OS images.  186  IBM z14 (3906) Technical Guide Figure 4-6 z14 Parallel Sysplex coupling connectivity