History of Network Operating Systems

Nowadays, practically every personal computer is connected in one form or another to a network. There exists of course the biggest network of all —the Internet— but several other types of smaller networks like LANs (local area networks) and enterprise networks also exist. Network operating systems (NOS) serve as gatekeepers to data and applications on all manner of these networks. Network operating systems don't differ too much from the single-processor operating systems almost every computer user is familiar with, says Andrew Tannenbaum in his book "A History of Operating Systems", but they have their own unique, fascinating history.

Birth of Networks
The concept of data communications between computers began in the late 1960s and early 1970s, when researchers began developing a way of connecting computers and exchanging information by way of packets of data. Soon, the concept of a local area network (LAN) took hold, replacing the previous model of a central computing node and so-called "dumb" terminals connected to it, as in IBM's proprietary Systems Network Architecture (SNA) model. The development later on of TCP/IP (Transmission Control Protocol/Internet Protocol) and Ethernet fostered the networking concept even further. The need soon came for operating systems to not only deal with the inter-connectivity of the networks but also the security aspect, according to a research paper from the American University Computing History Museum.

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