The

The From the home of the codebreakers and the birthplace of modern computing, this is the Bletchley Park podcast.

Welcome to this additional episode of the Bletchley Park podcast.

Sixter.

The way in which the secrets of Bletchley Park were finally revealed to the world,

bit by bit, and now, over the course of nearly four decades,

has meant that many myths and misunderstandings have

become embedded in the story. One of our goals with these podcasts is to tell the full story

of the codebreakers and along the way hopefully correct some of those errors. So in this It

Happened Here episode we'll take a deep dive into traffic analysis, a topic that we've

mentioned in many episodes and for years has been thought of as just another step in

the path of breaking a message.

Our research officer, Dr Thomas Cheatham, will argue that in fact it was a fully-fledged

source of intelligence in its own right.

He'll guide us through not only the history and processes

of traffic analysis but also those of Sixta, the section at Bletchley Park, most famously

known for producing it. Very special thanks go to Dr Ben Thompson and Owen Mugan for

voicing our archival documents.

This is Bletchley Park.

It happened here.

We've spoken about traffic analysis, countless times in this podcast over the years, but generally only in passing.

So, Thomas, my first question to you is the easy one. What is traffic analysis?

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