https://rs-485.com/index.php?action=history&feed=atom&title=ESCONESCON - Revision history2026-05-04T14:31:40ZRevision history for this page on the wikiMediaWiki 1.42.3https://rs-485.com/index.php?title=ESCON&diff=514&oldid=prevRS-485: Imported from Wikipedia (overwrite)2026-05-02T18:04:19Z<p>Imported from Wikipedia (overwrite)</p>
<p><b>New page</b></p><div>{{Short description|IBM data connection}}<br />
{{Refimprove|date=December 2009}}<br />
{{Use dmy dates|date=July 2020}}<br />
[[Image:ESCON cable.JPG|thumb|280px|ESCON cable with connectors]]<br />
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'''ESCON''' (Enterprise Systems Connection) is a data connection created by [[IBM]], and is commonly used to connect their [[mainframe computer]]s to peripheral devices such as [[disk storage]], [[tape drive]]s and [[IBM 3270]] display controllers. ESCON is an [[optical fiber]], [[half-duplex]], [[Serial communications|serial]] interface. It originally operated at a rate of 10{{nbsp}}MB/s, which was later increased to 17{{nbsp}}MB/s. The current maximum distance is 43 kilometers.{{Citation needed|date=December 2021}}<br />
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IBM introduced ESCON<ref>{{cite web<br />
| title = IBM ENTERPRISE SYSTEMS CONNECTION ARCHITECTURE OVERVIEW<br />
| id = 190-134<br />
| date = September 5, 1990<br />
| url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/4/897/ENUS190-134/index.html<br />
| work = Announcement Letters<br />
| publisher = IBM<br />
}}<br />
</ref> in September 1990 as part of its System/390 announcement.<ref><br />
{{cite book<br />
|date=September 5, 1990<br />
|title=System/390 processors, systems, functions designed to meet customer needs in the '90s<br />
|publisher=IBM<br />
|pages= 13–14<br />
}}</ref><ref>{{cite web<br />
| title = IBM SYSTEM/390 OVERVIEW: A NEW ERA BEGINS<br />
| id = 190-123<br />
| date = September 5, 1990<br />
| url = https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/3/897/ENUS190-123/index.html<br />
| work = Announcement Letters<br />
| publisher = IBM<br />
}}<br />
</ref> It replaced the older, slower (4.5{{nbsp}}MB/s), copper-based, parallel, [[IBM System/360]] [[Bus and Tag]] channels technology of 1960-1990 era mainframes. Optical fiber is smaller in diameter and weight, and hence could save installation costs. Space and labor could also be reduced when fewer physical links were required - due to ESCON's switching features. ESCON is being supplanted by the substantially faster [[FICON]], which runs over [[Fibre Channel]].<br />
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ESCON allows the establishment and reconfiguration of channel connections dynamically, without having to take equipment off-line and manually move the cables. ESCON supports channel connections using serial transmission over a pair of fibers. The ESCON Director supports dynamic switching (which could be achieved prior to ESCON, but not with IBM-only products). It also allows the distance between units to be extended up to 60&nbsp;km over a dedicated fiber. "Permanent virtual circuits" are supported through the switch.<br />
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ESCON switching has advantages over a collection of point-to-point links. A peripheral previously capable of accessing a single mainframe can now be connected simultaneously to up to eight mainframes, providing peripheral sharing.<br />
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The ESCON interface specifications were adopted as ANSI X3.296:1997 by the [[ANSI]] X3T11 committee.<ref>{{cite web |url=http://dptgw01.dpt.com/t11/stat.nsf/a7ccfb30e1e61c76852566dc004c7fae/d67c187a33adcf638525660b0071c1b2?OpenDocument |url-status=dead |archive-url=https://web.archive.org/web/20000411125033/http://dptgw01.dpt.com/t11/stat.nsf/a7ccfb30e1e61c76852566dc004c7fae/d67c187a33adcf638525660b0071c1b2?OpenDocument |archive-date=2000-04-11 |title=SBCON}}</ref><ref>{{cite book |url=https://webstore.ansi.org/standards/incits/ansiincits2961997r2002 |title=ANSI INCITS 296-1997 (R2002) - Information Technology--Single-Byte Command Code Sets CONnection (SBCON) Architecture (Formerly ANSI X3.296-1997)}}</ref><ref name="DeCusatisDeCusatis2006">{{cite book|author1=Casimer DeCusatis|author2=Carolyn J. Sher DeCusatis|title=Fiber optic essentials|url=https://books.google.com/books?id=c-B990MwuPkC&pg=PA154|year=2006|publisher=Academic Press|isbn=978-0-12-208431-7|pages=154–155}}</ref><br />
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==See also==<br />
* [[Direct access storage device]] (DASD)<br />
* Most important DASD ([[disk arrays]]) with ESCON interfaces:<br />
** [[EMC Symmetrix]], DMX and VMAX families.<br />
** [[Hewlett Packard Enterprise]] [[HP XP|XP Storage]] family.<br />
** [[Hitachi Data Systems]] Lightning<br />
** [[IBM Enterprise Storage Server]] (Shark)<br />
** IBM [[IBM Storage|Storage DS8000]]<br />
** [[Sun StorageTek]] SVA<br />
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==References==<br />
{{Reflist}}<br />
<br />
{{DEFAULTSORT:Escon}}<br />
[[Category:Computer storage devices]]<br />
[[Category:Fiber-optic connectors]]<br />
[[Category:Mainframe computers]]<br />
[[Category:IBM System/360 mainframe line]]</div>RS-485