/FIRST AND FINAL ADD NY010 -- IBM ESCON FACT SHEET/
/FIRST AND FINAL ADD NY010 -- IBM ESCON FACT SHEET/
EXTENDING THE REACH OF ESCON
IBM CUSTOMERS TO BENEFIT FROM NEW AMERITECH OFFERING
WHITE PLAINS, N.Y., June 16 /PRNewswire/ -- IBM (NYSE: IBM) today welcomed an announcement by Ameritech that it plans to provide Host Interconnect Service for ESCON (See Note) to its customers. This service will provide transmission of Enterprise Systems Connection Architecture (See Note) protocol data between customers' mainframe processors and peripherals such as disk and tape drives or communications front-end processors, beyond the boundaries of customer premises.
"IBM is delighted Ameritech plans to introduce this service," said David M. Thomas, IBM vice president and general manager, marketing, IBM United States. "Our ES/9000 (See Note) customers in the Great Lakes area will be able to order ESCON connections to buildings across the street or miles away as easily as they order telephone lines today."
"As ESCON users ourselves, it's easy for us to see our customers' need for long-distance channel connections in designing enterprise-wide computing systems," said David M. Friedman, vice president and general manager of product development and data strategy implementation for the five Ameritech Bell companies. "Host Interconnect Service is an important part of the portfolio of enhanced data services Ameritech is developing to meet our customers' increasingly complex data connectivity needs."
Ameritech is the Chicago-based parent company of the Bell companies serving Illinois, Indiana, Michigan, Ohio and Wisconsin, as well as several other information-related subsidiaries.
ESCON is a channel architecture for connecting IBM's System/390 (See Note) computers to peripherals at distances up to 60 kilometers, or approximately 37 miles. (See ESCON fact sheet below.) The published protocol also may be used by non-IBM vendors either to connect processors and I/O devices or to interconnect processors.
Ameritech said its Host Interconnect Service will provide a dedicated optical fiber circuit enabling customers to extend their ESCON channel connections outside a campus environment. The service will link two customer sites in a point-to-point configuration with a dedicated connection supporting transmission rates of 200 megabits per second.
Ameritech said it plans to make Host Interconnect Service available beginning first quarter, 1993.
ESCON FACT SHEET
IBM announced Enterprise Systems Connection Architecture (ESCON) in September 1990. It was the most extensive change IBM had made to its mainframe input/output (I/O) channels since System/360 was introduced in 1964.
Channels are paths along which data is sent from the processor to its I/O devices -- disk drives, tape drives, printers or the displays used by end-users. Before the introduction of ESCON, IBM large systems provided only parallel channels, which require two copper cables (known as bus and tag) to connect each I/O device or its control unit to a channel.
ESCON combines the latest technology in hardware, software and protocols to provide customers many advantages over parallel channels without requiring any changes in customer applications. ESCON includes the following elements.
-- Fiber optic cables transmit data serially for longer distances and with greater speed, accuracy and security than is possible on parallel channels with copper cable.
-- ESCON Directors are hardware dynamic switching devices to which all ESCON channels and I/O devices can be attached.
-- ESCON Manager is software that provides a single point of control for managing a data center in an ESCON environment.
-- ESCON extended distance feature (ESCON XDF -- See Note --) allows I/O devices to be placed farther from the processor.
-- ESCON Multiple Image Facility (EMIF) allows sharing of ESCON channels among Processor Resource/Systems Manager (PR/SM -- See Note --) logical partitions of selected ES/9000 processors.
With ESCON, data can be transmitted at up to 10 megabytes (MB) per second with less disruption than the 4.5 MB-per-second rate possible on parallel channels. (Speeds of up to 17 MB per second are possible on ES/9000 520-based processors.)
Equally important, ESCON brings dramatic changes to a customer's traditional "glass house" or data center by making it easier to connect and reconnect processors and their I/O devices.
As businesses reorganize, decentralize and merge, end users may suddenly need access to new data bases and applications, requiring I/S departments to reconfigure their computer systems. Business cycles, such as special promotions, seasonal peaks, and end-of-year closings may require reconfigurations as well.
ESCON makes it easy to connect all the processors in a data center to all the storage control units and display control units using the ESCON Director as a central connecting device. The Director serves as a dynamic switch. Using ESCON Manager, operators can "look at" the I/O configurations of an entire data center from one console, issue a command to the ESCON Director, and reconfigure systems easily.
ESCON also makes it possible to disconnect or connect new I/O devices without stopping the whole computer system, which was necessary when connecting devices to parallel channels.
The physical characteristics of fiber also make ESCON channels far easier to install than parallel channels. ESCON uses a glass fiber about one tenth the diameter of a human hair. ESCON supports trunk cables containing 144 fibers, providing links for 72 channels in a cable a half-inch in diameter that weighs about l.3 ounces per foot.
A single copper cable is about 1 and 1/4 inches in diameter. Two copper cables provide the connection for only one channel and weigh about a pound per foot, giving ESCON almost a thousand-fold weight saving over bus and tag cables.
And the high reliability of fiber optics and serial transmission means I/O devices connected to ESCON channels can be located at great distances from the processor. (I/O devices connected to parallel channels are limited to a maximum of 400 feet from the processor.) Maximum distances for ESCON channels with ESCON XDF are:
-- 37.2 miles (60 km) for channel-to-channel (CTC) connections between processors;
-- 26.7 miles (43 km) for 3172 Interconnect (LAN) controllers, 3174 subsystem (display) controllers, and 9343 direct access storage device (DASD) subsystems;
-- 14.3 miles (23 km) for 3490 tape drives and the 3495 Tape Library Dataserver;
-- 9.3 miles (15 km) for 3990/3390 DASD subsystems using Model 2 and 3 storage controls.
Note: Trademark or registered trademark of IBM Corporation.
/CONTACT: Diane E. Whitehead of IBM, 914-642-4668, or Jeffrey Smith of Ameritech, 708-248-2138/
(IBM AIT) CO: International Business Machines Corp.; Ameritech ST: New York, Illinois IN: CPR SU: PDT SH -- NY010A -- 0517 06/16/92 09:20 EDT