The Open Systems Interconnection Model

The early need for network computers was born out of the desire to share resources, specifically, printer resources. During the mid-1980s to early 1990s, very few systems were networked. This was due in large part to incompatible technologies. Companies started to recognize that they needed to buy a printer for each employee, even though each employee typically used the printer infrequently. Simply put, it was bad business. Companies decided it would make sense to share the printer among multiple users, thereby reducing costs and overhead. The early corporate networks were largely glorified methods to share printer resources.

As time progressed though, companies started to consider sharing other resources. ...

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