The National Crime Agency believes he may have assaulted many more youngsters he had contact with through his 25-year career in schools and as a senior Scouts volunteer.
Prosecutor Ruona Iguyovwe said: ‘This ranks as one of the most serious I have dealt with as a prosecutor.
A prolific paedophile has admitted 45 sex offences against children in Britain and abroad in one of the worst cases to come court.
He has developed tools for downloading and analysing Web sites, blogs and social networking sites, including the research Web crawler Soc Sci Bot and software for statistical and topological analyses of site structures (through links) and site content (through text).
He has published 152 refereed journal articles, seven book chapters, and two books including Introduction to Webometrics, is an associate editor of the Journal of the American Society for Information Science and Technology and sits on eight other editorial boards.
Indeed, having interviewed many veterans over the years, the overwhelming impression was that they looked back on their service in the First World War with a mixture of nostalgia and affection, tinged with sadness at the loss of friends.
Above all else, the one emotion that helped them keep their sense of perspective and enabled them to endure the bad times was their uniquely British sense of humour, which appeared in even the grimmest situations, and it was the funny stories that they most often regaled us with.