BESM-6 computer was a real masterpiece - the first second-generation supercomputer, made by the scientific group of the Academy of Science of the USSR.
Lebedev initiated and took an active hand in the mathematical modeling of the future machine.
Finally, and quite importantly, on the initiative of S.A.Lebedev, all diagrams of BESM-6 were formulated with Boolean algebra.
The main features of the BESM-6 were: an address-bus control system or as Lebedev called it in 1964, "plumbing". According to this control principle, the flow of commands and operands was processed in parallel (up to 8 machine commands at each stage); the use of associative memory on superspeed registers reduced the number of retrieval calls to the ferric memory. This allowed for a localized optimization of calculation according to the dynamics: a stratification of operating memory into autonomous modules, which enabled simultaneous, multi-directional calls to memory units; a multi-program operational mode for simultaneous work on several problems with specified priorities; a hardware mechanism for transformation of mathematical addresses to physical ones, which made it possible for a dynamic distribution of the operating memory in the computational process by means of an operational system; a paged system of organizational memory which in its turn developed protection mechanisms for numbers and commands; an up-to-date system interrupt which facilitated the automatic transfer from one solution of a problem to another, accessing external units and controlling their operation.
The electronic circuits of BESM-6 consisted of 60 thousand transistors and 180 thousand semiconductor-diodes. The elemental base of BESM-6 was quite new at that time and laid the foundations of circuit engineering for third and fourth-generation computers. The principle of dividing complex machine logic built on diode blocks using a single transistor amplification guaranteed a simplified manufacturing process and a reliable operation. The computer was now achieving average speeds of up to one million operations per second.
The BESM-6 prototype was launched into trial operation in 1965, and by the middle of 1967, the first manufactured model was tested. Three additional models were made at the same time.
On the basis of BESM-6, centres of collective use were established which facilitated real-time control systems, coordination of data teleprocessing systems, and others. The machine was used for simulating complex physical processes and control processes, and also, for development of new computer software in designing systems. The principle technical design laid out during BESM-6's development gave the computer an enviable service life: BESM-6 was produced over the course of 17 years! The computer had a good reputation among users and in the 70's, became the model for high-speed computers.
During the Soviet-American space flight of "Apollo-Soyuz", the controls were carried out at a new computer complex which included the BESM-6 and other domestic high-speed computers which had been developed by S.A.Lebedev's pupils. Earlier, the call for telemetry data processing might have taken roughly half an hour. Now, using the new complex, the work was performed in a minute. All data processing was done by Soviet scientists, half an hour earlier than by their American colleagues.
The chief designers of BESM-6 (S.A.Lebedev, V.A.Melnikov, L.N.Koroliov, L.A.Zak, V.N.Laut, A.A.Sokolov, V.I.Smirnov, A.N.Tomilin and M.V.Tiapkin) won the State Prize.