History Of LANs
History of LANs
Data Communications began in the 1960s with an emphasis on communication over long distances — at least between different cities and often over much greater distances — but at relatively slow data transfer rates. At that time, that was what was needed. Most computing was done in batch mode, and companies needed an efficient way to transmit data processing files between computer sites. In the 1970s, interactive terminals began to proliferate, but most data communications took place over long distances. For example, transaction-processing between a computer center in the suburbs and interactive terminals downtown.
LANs have flourished over the past decade to become an integral part of the office environment. Many LAN technologies have been introduced, but only a few have proven themselves and become readily accepted.
In this section, some of the more popular LAN technologies will be examined. Each one will be described according to its history, features and traditional configuration. The features of each will be described according to the LAN architecture features described in Chapter 1— transmission medium, topology, access control, transmission technique and speed.
Under the heading of traditional LAN technologies, the following will be examined:
• ARCnet.
• Ethernet.
• Token-ring.
• AppleTalk.
The world of LANs is dynamic, and while certain technologies have earned wide acceptance in the marketplace, newer ones are always being introduced.
ARCnet (Attached Resource Computing Network) was developed by John Murphy at
Datapoint Corporation in 1977. At that time, it was introduced as a LAN solution for owners of Datapoint computers. The company began licensing its technology to other manufacturers in the early 1980’s, which led to PC-based ARCnet LANs.
ARCnet’s initial popularity was due to its use of the same type of coax cabling as IBM 3270 terminals. Customers could purchase PCs, place them on users’ desks, remove the cable from the terminal,
Data Communications began in the 1960s with an emphasis on communication over long distances — at least between different cities and often over much greater distances — but at relatively slow data transfer rates. At that time, that was what was needed. Most computing was done in batch mode, and companies needed an efficient way to transmit data processing files between computer sites. In the 1970s, interactive terminals began to proliferate, but most data communications took place over long distances. For example, transaction-processing between a computer center in the suburbs and interactive terminals downtown.
LANs have flourished over the past decade to become an integral part of the office environment. Many LAN technologies have been introduced, but only a few have proven themselves and become readily accepted.
In this section, some of the more popular LAN technologies will be examined. Each one will be described according to its history, features and traditional configuration. The features of each will be described according to the LAN architecture features described in Chapter 1— transmission medium, topology, access control, transmission technique and speed.
Under the heading of traditional LAN technologies, the following will be examined:
• ARCnet.
• Ethernet.
• Token-ring.
• AppleTalk.
The world of LANs is dynamic, and while certain technologies have earned wide acceptance in the marketplace, newer ones are always being introduced.
ARCnet (Attached Resource Computing Network) was developed by John Murphy at
Datapoint Corporation in 1977. At that time, it was introduced as a LAN solution for owners of Datapoint computers. The company began licensing its technology to other manufacturers in the early 1980’s, which led to PC-based ARCnet LANs.
ARCnet’s initial popularity was due to its use of the same type of coax cabling as IBM 3270 terminals. Customers could purchase PCs, place them on users’ desks, remove the cable from the terminal,