Resource Sharing: programs (O.S., applications), data, equipment (printers, disks) are available to all users of the network regardless of location.
Many organizations have a substantial number of computers in operation, often located far apart. A company with many factories may have a computer at each location to keep track of inventories, monitor productivity, and do the local payroll. That is Resource sharing, and the goal is to make all programs, equipment, and especially data available to anyone on the network without regard to the physical location of the resource and the user.
High reliability: By replicating files on different machines and having spare CPUs; users are more immune from hardware/software failure.
A second goal is to provide high reliability by having alternative sources of supply. In addition having multiple CPU’s means that if one goes down, the others may be able to take over its work, although reduced performance. Military, banking, air traffic Control, Nuclear reactor safety, and many other applications.
Less cost: Small machines have about 1/10 the power of a mainframe but 1/1000 the cost. By using such machines with file server machine(s), a local area network LAN can be cheaply installed. It is easy to increase the capacity by adding new machines.
Another goal is to save money. Small computers have a much better price/performance ratio than large ones. In this model, the users are called clients, and the whole arrangement is called the client-server model. Another networking goal is scalability, the ability to increase system performance gradually as the workload grows just by adding more processors. With centralized mainframes, when the system is full, it must be replaced by a larger one, usually at great expense and even greater disruption to the users. A computer network can provide a powerful Communication medium among widely separated employees.
Many organizations have a substantial number of computers in operation, often located far apart. A company with many factories may have a computer at each location to keep track of inventories, monitor productivity, and do the local payroll. That is Resource sharing, and the goal is to make all programs, equipment, and especially data available to anyone on the network without regard to the physical location of the resource and the user.
High reliability: By replicating files on different machines and having spare CPUs; users are more immune from hardware/software failure.
A second goal is to provide high reliability by having alternative sources of supply. In addition having multiple CPU’s means that if one goes down, the others may be able to take over its work, although reduced performance. Military, banking, air traffic Control, Nuclear reactor safety, and many other applications.
Less cost: Small machines have about 1/10 the power of a mainframe but 1/1000 the cost. By using such machines with file server machine(s), a local area network LAN can be cheaply installed. It is easy to increase the capacity by adding new machines.
Another goal is to save money. Small computers have a much better price/performance ratio than large ones. In this model, the users are called clients, and the whole arrangement is called the client-server model. Another networking goal is scalability, the ability to increase system performance gradually as the workload grows just by adding more processors. With centralized mainframes, when the system is full, it must be replaced by a larger one, usually at great expense and even greater disruption to the users. A computer network can provide a powerful Communication medium among widely separated employees.
No comments:
Post a Comment