Bletchley's code-breaking effort shortened the war by many months

A closer look at the Colossus computer

An amateur cryptographer who beat the British World War II computer Colossus in a code-cracking challenge has been honoured for his skills.

Joachim Schueth solved a German cipher in just 46 seconds, more than three hours quicker than the 60 year old PC.

He received a prize from the National Museum of Computing, which included a valve from the Colossus machine.

Mr Schueth deciphered the code using a laptop and a program he wrote specifically for the challenge.

Joachim Schueth (L) and Tony Sale (R) Colossus loses challenge

"It was unfair because I was using a modern PC, while Colossus was created more than 60 years ago," he said. "It really is astonishing and humbling that the world's first programmable, digital computer was created in the 1940s."

The Cipher Challenge took place in November 2007 at Bletchley Park, the home of early UK computing efforts, and marked the end of a project to rebuild Colossus.

Tony Sale, who has spent the last 14 years rebuilding the machine said: "Joachim really showed how things have advanced from the days of Colossus."

"As well as recapturing the excitement that the Bletchley Park code breakers must have felt, the Cipher Challenge has more importantly highlighted the magnitude of their achievement, their tenacity and their ingenuity."

Secret workings

Mr Schueth competed against other code breakers and a Colossus Mark II machine last November.

The target messages were encoded with a Lorenz S42 machine - as used by the German high command - and were transmitted by a team of radio enthusiasts in Paderborn, Germany.

The re-built Colossus Enlarge Image

Colossus, the size of a bus and widely recognised as being one of the first recognisably modern computers, took three hours and fifteen minutes to unravel the code.

Mr Schueth and his machine took just 46 seconds.

"My laptop digested ciphertext at a speed of 1.2 million characters per second - 240 times faster than Colossus," he said.

"If you scale the CPU frequency by that factor, you get an equivalent clock of 5.8 MHz for Colossus. That is a remarkable speed for a computer built in 1944.

"Even 40 years later many computers did not reach that speed."

There were 10 Colossus machines built in the 1940s.

They were key in shortening the war by revealing troop movements to the UK armed forces.

All of the machines they were broken up after the war in a bid to keep their workings secret.