Computer organization and architecture by william stallings pdf

Network computer devices that originate, route and terminate the data are called network nodes. Two such devices can be said to be networked together when one device is able to exchange information with the other device, whether or not computer organization and architecture by william stallings pdf have a direct connection to each other.

The best-known computer network is the Internet. In the late 1950s, early networks of computers included the U. In 1979, Robert Metcalfe pursued making Ethernet an open standard. By 1998, Ethernet supported transmission speeds of a Gigabit. A network allows sharing of network and computing resources. Users may access and use resources provided by devices on the network, such as printing a document on a shared network printer or use of a shared storage device. A network allows sharing of files, data, and other types of information giving authorized users the ability to access information stored on other computers on the network.

Packets are sent through the network to their destination. Once the packets arrive they are reassembled into their original message. When one user is not sending packets, the link can be filled with packets from other users, and so the cost can be shared, with relatively little interference, provided the link isn’t overused. Often the route a packet needs to take through a network is not immediately available. The physical layout of a network is usually less important than the topology that connects network nodes.

Most diagrams that describe a physical network are therefore topological, rather than geographic. The symbols on these diagrams usually denote network links and network nodes. 1 and 2 — the physical layer and the data link layer. Ethernet transmits data over both copper and fiber cables. The orders of the following wired technologies are, roughly, from slowest to fastest transmission speed. The insulation helps minimize interference and distortion. Transmission speed ranges from 200 million bits per second to more than 500 million bits per second.