Phil Hayes working on Colossus
Phil Hayes gave a talk about the history and development of ERNIE (Electronic Random Number Indicator Engine), a hardware random number generator used by Premium Bonds to distribute prizes to bondholders in a monthly lottery. Over the years there have been five generations of ERNIE. In the early days all winning numbers were held on index cards and had to be looked through manually. Today, 3 million numbers are generated in just 12 minutes per month.
The first ERNIE was built at the Post Office Research Station at Dollis Hill by a team led by Sidney Broadhurst. The designers were Tommy Flowers and Harry Fensom who were part of the original team who built the wartime Colossus, one of the world’s first digital computers, designed to break the Lorenz Cypher used by the German High Commander to send secret message.
An early example of ERNIE
It was introduced in 1957, with the first draw on 1 June, and generated bond numbers from the electronic noise created by neon tubes. ERNIE 1 is in the collections of the Science Museum in London.
ERNIE 2 replaced the first ERNIE in 1972.
ERNIE 3 in 1988 was the size of a personal computer; at the end of its life it took five and a half hours to complete its monthly draw.
ERNIE 4 was brought into service in August 2004 in anticipation of an increase in prizes each month from September 2004. It was 500 times faster than the original, generating million numbers an hour; these are checked against a list of valid bonds. By comparison, the original ERNIE generated 2,000 numbers an hour and consisted of five 7′ cabinets.
ERNIE 4 used thermal noise in transistors to generate true random numbers. It is now in Bletchley Park’s National Museum of Computing.
ERNIE 5, the latest model, was brought into service in March 2019. It uses quantum technology to produce random numbers through light, replacing the former ‘thermal noise’ method. Running at speeds 21,000 times faster than the first ERNIE, it can produce 3 million winners in just 12 minutes each month.
