Editing Traffic analysis (section)

===World War I===
* British analysts during [[World War I]] noticed that the [[call sign]] of German Vice Admiral [[Reinhard Scheer]], commanding the hostile fleet, had been transferred to a land station. [[Admiral of the Fleet (Royal Navy)|Admiral of the Fleet]] [[David Beatty, 1st Earl Beatty|Beatty]], ignorant of Scheer's practice of changing call signs upon leaving harbour, dismissed its importance and disregarded [[Room 40]] analysts' attempts to make the point. The German fleet sortied, and the British were late in meeting them at the [[Battle of Jutland]].<ref name="Kahn">{{cite book
 | title = The Codebreakers: The Story of Secret Writing
 | url = https://archive.org/details/codebreakerssto00kahn
 | url-access = registration
 | author = Kahn, David
 | year = 1974
 | id = Kahn-1974
 | publisher = Macmillan 
 | isbn = 0-02-560460-0
 }}</ref> If traffic analysis had been taken more seriously, the British might have done better than a "draw".{{original research inline|date=August 2009}}
* French military intelligence, shaped by [[Auguste Kerckhoffs]]'s legacy, had erected a network of intercept stations at the Western Front in pre-war times. When the Germans crossed the frontier, the French worked out crude means for direction-finding based on intercepted signal intensity. The recording of call signs and of traffic volumes further enabled the French to identify German combat groups and to distinguish fast-moving cavalry from slower infantry.<ref name="Kahn"/>