Chapter 3. I/O system structure 93
Draft Document for Review April 7, 2004 6:15 pm 6947ch03.fm
Tabl e no tes :
1. SM is single mode fiber.
2. MM is multimode fiber.
3. OSA-E refers to OSA-Express.
4. Brought forward to z990 on an upgrade only.
5. The OSA-Express GbE features brought forward from an upgrade have a different connector (SC
Duplex) than the new OSA-E GbE features.
6. 1000BASE-T is the new Ethernet feature.
7. UTP is Unshielded Twisted Pair.
8. STP is Shielded Twisted Pair.
3.4.2 ESCON channel
Following are z990 connectivity options in the ESCON I/O interface environment.

z990 16-port ESCON feature

The z990 16-port ESCON feature (feature code 2323) occupies one I/O slot in the z990 I/O
cage. Each port on the feature uses a 1300 nanometer (nm) light-emitting diode (LED)
transceiver, designed to be connected to 62.5 micron multimode fiber optic cables only.
The feature has 16 ports with one PCHID associated with each port, up to a maximum of 15
active ESCON channels per feature. There is a minimum of one spare port per feature, to
allow for channel sparing in the event of a failure of one of the other ports.
The16-port ESCON feature port utilizes a small form factor optical transceiver that supports a
new fiber optic connector called MT-RJ. The MT-RJ is an industry standard connector which
has a much smaller profile compared with the original ESCON Duplex connector. The MT-RJ
connector, combined with technology consolidation, allows for the much higher density
packaging implemented with the 16-port ESCON feature.
2366 4OSA-E Fast Ethernet 6RJ-45 Category 5 UTP
2367 OSA-E Token Ring RJ-45 UTP or STP 8
Feature code Feature name Connector type Cable type
Note: The z990 16-port ESCON feature does not support a multimode fiber optic cable
terminated with an ESCON Duplex connector. However, 62.5 micron multimode ESCON
Duplex jumper cables can be reused to connect to the 16-port ESCON feature. This is
done by installing an MT-RJ/ESCON Conversion kit between the 16-port ESCON
feature MT-RJ port and the ESCON Duplex jumper cable. This protects the investment
in the existing ESCON Duplex cabling plant.
Fiber optic conversion kits and Mode Conditioning Patch (MCP) cables are not
orderable as features on z990. Fiber optic cables, cable planning, labeling, and
installation are all customer responsibilities for new z990 installations and upgrades.
As mentioned, IBM Fiber Cabling Services offer a total cable solution service to help with
your cable ordering needs, and is highly recommended.