Up to 80 FICON Express2 Channels

long wavelength (LX) and short wavelength (SX) features, though the LX and SX cannot be intermixed on a single feature. Note, the maximum quantity of FICON Express, OSA-Express, PCICA, and PCIXCC features in combina- tion cannot exceed 20 features per server.

Up to 80 FICON Express2 channels are supported on the z890. This offers a 100% increase in FICON channels over the z800. FICON Express2 is available in long wavelength (LX) and short wavelength (SX) features. Each FICON Express2 feature has four independent ports which support four channels per card. The LX and SX cannot be intermixed on a single feature. The maximum number of FICON Express2 features that can be installed in the I/O cage is 20.

The z890 supports up to 80 FCP channels for attachment to Small Computer System Interface (SCSI) disks in a Linux environment. The same four-port FICON Express2 feature card used for FICON Express2 channels can also be used for Fibre Channel Protocol (FCP) channels. FCP channels are enabled on these existing features via a Licensed Inter- nal Code (LIC) with a unique mode of operation and CHPID deﬁ nition (FCP). FCP is available in long wavelength (LX) and short wavelength (SX) features, though the LX and SX cannot be intermixed on a single feature. Note, the maxi- mum quantity of FICON Express, FICON Express2, OSA- Express, OSA-Express2, PCICA, and PCIXCC features in combination cannot exceed 20 features per server.

InterSystem Channel-3 (ISC-3)

A four link ISC-3 feature is provided on the z890 family of servers. It consists of a mother card with two daughter cards each with two links. Each link is capable of operating 1 giga- bits per second (Gbps) in Compatibility Mode or 2 Gbps in

peer mode up to an unrepeated distance of 10 km (6.2 miles). The mode is selected for each link via the CHPID type in the IOCDS. ISC-3 links are ordered in increments of one. It is rec- ommended that an initial order for ISC-3 include two links.

ISC-3 links in Compatibility Mode must be used for connec- tivity to 9672s (ICB-2 links are not supported on the z890).

An RPQ card (8P2197) is available to allow ISC-3 dis- tances up to 20 km. This card runs in Peer Mode at 1 Gbps and/or Compatibility Mode at 1 Gbps. A unique daughter card with two links per card is shipped.

Integrated Cluster Bus-3 (ICB-3)

The ICB-3 feature is a coupling link used to provide high- speed communication between z990 and z890 servers and z900 and z800 General Purpose Servers and Cou- pling Facilities over a short distance (less than 7 meters). The ICB-3 is supported via an STI-3 card which resides in the I/O cage and converts the 2.0 GBps input into two 1 GBps ICB-3s.

Integrated Cluster Bus-4 (ICB-4)

The ICB-4 feature is a coupling link used to provide high-speed communication between a z990 and/or z890 servers over a short distance (less than 7 meters). The ICB-4 consists of one link that attaches directly to a 2.0 GBps STI port on the server and does not require connec- tivity to an I/O cage.

Internal Coupling Channel (IC)

IC links emulate the coupling links between images within a single server. IC links are deﬁ ned in the IOCP. There is no physical channel involved. A z/OS image can connect to a Coupling Facility on the same server using IC capabilities.