Queueing Theory Cloud Computing

Most capacity planning is based around queueing theory, which is the mathematical study of waiting lines. Agner Krarup Erlang, a Danish engineer working for the Copenhagen Telephone Exchange, published the first paper on queueing theory in 1909. It explains (among other things) the powerful relationship between resource utilization and response time. Queueing theory was used to develop modern packet-switching networks that became the basis for developing the Internet. Important work was performed by Leonard Kleinrock in the early 1960s.

Queueing means standing in line waiting for resources to become available. Aside from being the British national pastime (David can say that, as he was born one of Her Majesty’s loyal subjects, by “facts of birth” as the passport says), it is the only word in the English language with five consecutive vowels (in its British spelling queueingwhich we adopt here as this spelling was adopted by the leading journal in the field, Queueing Systems). In the next few paragraphs we explain everything you need to know about queueing but didn’t know you needed to ask.