The IBM System z10 BC also takes advantage of

Infi niBand as a higher-bandwidth replacement for the Self- Timed Interconnect (STI) I/O interface features found in prior System z servers.

Infi niBand coupling links are CHPID type CIB.

Coupling Connectivity for Parallel Sysplex

Five coupling link options: The z10 BC supports Internal Coupling channels (ICs), Integrated Cluster Bus-4 (ICB-4), InterSystem Channel-3 (ISC-3) (peer mode), and 12x and 1x Infi niBand (IFB) links for communication in a Parallel Sysplex environment.

1)Internal Coupling Channels (ICs) can be used for inter- nal communication between Coupling Facilities (CFs) defi ned in LPARs and z/OS images on the same server.

2)Integrated Cluster Bus-4 (ICB-4) links are for short distances. ICB-4 links use 10 meter (33 feet) copper cables, of which 3 meters (10 feet) is used for internal routing and strain relief. ICB-4 is used to connect z10 BC-to-z10 BC, z10 EC, z9 EC, z9 BC, z990, and z890. Note: If connecting to a z9 BC or a z10 BC with ICB-4, those servers cannot be installed with the non-raised

oor feature. Also, if the z10 BC is ordered with the non- raised fl oor feature, ICB-4 cannot be ordered.

3)InterSystem Channel-3 (ISC-3) supports communi- cation over unrepeated distances of up to 10 km (6.2 miles) using 9 micron single mode fi ber optic cables and even greater distances with System z qualifi ed opti- cal networking solutions. ISC-3s are supported exclu- sively in peer mode (CHPID type CFP).

4)12x InfiniBand coupling links (12x IB-SDR or 12x

IB-DDR)offer an alternative to ISC-3 in the data center and facilitate coupling link consolidation; physical links can be shared by multiple systems or CF images on a single system. The 12x IB links support distances up to 150 meters (492 feet) using industry-standard OM3 50 micron fi ber optic cables.

System z now supports 12x Infi niBand single data rate (12x IB-SDR) coupling link attachment between System z10 and System z9 general purpose (no longer limited to standalone coupling facility)

5)Long Reach 1x InfiniBand coupling links (1x IB- SDR or 1x IB-DDR) are an alternative to ISC-3 and offer greater distances with support for point-to-point unrepeated connections of up to 10 km (6.2 miles) using 9 micron single mode fi ber optic cables. Greater distances can be supported with System z qualifi ed optical networking solutions. Long reach 1x Infi niBand coupling links support the same sharing capability as the 12x Infi niBand version allowing one physical link to be shared across multiple CF images on a system.

Note: The Infi niBand link data rates do not represent the performance of the link. The actual performance is depen- dent upon many factors including latency through the adapters, cable lengths, and the type of workload. Specifi - cally, with 12x Infi niBand coupling links, while the link data rate can be higher than that of ICB, the service times of coupling operations are greater, and the actual throughput is less.

Refer to the Coupling Facility Confi guration Options white- paper for a more specifi c explanation of when to continue using the current ICB or ISC-3 technology versus migrat- ing to Infi niBand coupling links.

The whitepaper is available at: http://www.ibm.com/ systems/z/advantages/pso/whitepaper.html.

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IBM Z10 BC manual Coupling Connectivity for Parallel Sysplex