Draft Document for Review April 7, 2004 6:15 pm

 

6947ch03.fm

 

 

 

 

 

 

 

Feature code

Feature name

Connector type

Cable type

 

 

 

 

 

 

 

 

2366 4

OSA-E Fast Ethernet 6

RJ-45

Category 5 UTP

 

 

2367

OSA-E Token Ring

RJ-45

UTP or STP 8

 

 

Table notes:

 

 

 

 

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.

3.4.2ESCON 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.

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.

Chapter 3. I/O system structure

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Image 107
IBM manual Escon channel, Z990 16-port Escon feature

990 specifications

The IBM 990 series, often referred to in the context of IBM's pioneering efforts in the realm of mainframe computing, represents a unique chapter in the history of information technology. Introduced in the late 1960s, the IBM 990 series was designed as a powerful tool for enterprise-level data processing and scientific calculations, showcasing the company's commitment to advancing computing capabilities.

One of the main features of the IBM 990 was its architecture, which was built to support a wide range of applications, from business processing to complex scientific computations. The system employed a 32-bit word length, which was advanced for its time, allowing for more flexible and efficient data handling. CPUs in the IBM 990 series supported multiple instructions per cycle, which contributed significantly to the overall efficiency and processing power of the machines.

The technology behind the IBM 990 was also notable for its use of solid-state technology. This provided a shift away from vacuum tube systems that were prevalent in earlier computing systems, enhancing the reliability and longevity of the hardware. The IBM 990 series utilized core memory, which was faster and more reliable than the magnetic drum memory systems that had been standard up to that point.

Another defining characteristic of the IBM 990 was its extensibility. Organizations could configure the machine to suit their specific needs by adding memory, storage, and peripheral devices as required. This modular approach facilitated the growth of systems alongside the technological and operational demands of the business environments they served.

In terms of software, the IBM 990 series was compatible with a variety of operating systems and programming environments, including FORTRAN and COBOL, enabling users to access a broader array of applications. This versatility was a significant advantage, making the IBM 990 an appealing choice for educational institutions, research facilities, and enterprises alike.

Moreover, the IBM 990 was engineered to support multiprocessing, which allowed multiple processes to run simultaneously, further increasing its effectiveness in tackling complex computing tasks.

In summary, the IBM 990 series represents a significant advancement in computing technology during the late 20th century. With a robust architecture, versatile configuration options, and a focus on solid-state technology, the IBM 990 facilitated substantial improvements in data processing capabilities, making it a cornerstone for many businesses and academic institutions of its time. Its impact can still be seen today in the continued evolution of mainframe computing.