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Plan 55-A

Automatic Telegraph Switching System Plan 55-A was one in a series of store and forward message switching systems developed by Western Union and used from 1948 to 1976 for processing telegrams. It is an automated successor to Plan 51, which commenced service in 1951 in a nationwide network of the U.S. Air Force, but required semi-automatic operation.

Technology, Operation & Overview

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Explore the main themes, entities and connections around Plan 55-A. Start with the topic map, then use the sections below for research and deeper semantic analysis.

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Overview

Operation

Queuing theory

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Map overview Semantic statistics

Plan 55-A

Nodes21
Edges20
Triples7
Avg. degree1.9
Density0.095238
Components1

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Plan 55-A

Top relations

related to External links · 4
Plan 55-A → America, Plan, Telegram, Western Union Telegraph Company
related to Queuing theory · 3
Plan 55-A → An, Leonard Kleinrock, Plan

Important terminology Word statistics

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Important terminology

message switching plan centers sending 55-a paper tape used console system western systems technology operation receiving reader sent cross-office telegram

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Plan 55-Arelated to External linksWestern Union Telegraph Company0.60section
Plan 55-Arelated to External linksTelegram0.60section
Plan 55-Arelated to External linksAmerica0.60section
Plan 55-Arelated to External linksPlan0.60section
Plan 55-Arelated to Queuing theoryAn0.60section
Plan 55-Arelated to Queuing theoryPlan0.60section
Plan 55-Arelated to Queuing theoryLeonard Kleinrock0.60section

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    Min side: 3
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