A session-layer protocol used to help find a node; for example, in a large internetwork.
A session-layer protocol used to help find a node; for example, in a large internetwork.
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=Networks, Nodes, Zones=
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In AppleTalk networks, every node has an official numerical address. In addition, a node may be part of a named group of nodes, which somehow belong together.
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Each AppleTalk network is assigned a unique network number, and each node in that network is assigned this number. Packets addressed to a node on the network must include the network number. In addition to a network number, each node has a node number that is unique within that network. This is an 8-bit number and can be any value between 1 and 254, inclusive (0 and 255 are reserved as node numbers). However, servers must have node numbers within the range of 128 to 254, and workstations must have numbers in the 1 to 127 range.
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A zone is a logical grouping of nodes. By restricting routing or searches to machines in a particular zone, network traffic and work can be reduced considerably. Accessing resources by zones also makes it easier to determine what is available for specific needs. A node may belong to more than one zone at the same time, or not be part of any zone. A zone can cross network boundaries; that is, a zone can consist of parts of two or more different networks or include multiple networks.