Table Of Contents

Z

Z

zero code suppression

Line coding scheme used for transmission clocking. Zero line suppression substitutes a 1 in the 7th bit of a string of eight consecutive zeros. See also ones density.

ZIP

Zone Information Protocol. AppleTalk session layer protocol that maps network numbers to zone names. ZIP is used by NBP to determine which networks contain nodes that belong to a zone. See also ZIP storm and zone.

ZIP storm

Broadcast storm that occurs when a router running AppleTalk propagates a route for which it currently has no corresponding zone name. The route is then forwarded by downstream routers, and a ZIP storm ensues. See also ZIP.

zone

1. Collection of all terminals, gateways, and multipoint control units (MCUs) managed by a single gatekeeper. A zone includes at least one terminal, and can include gateways or MCUs. A zone has only one gatekeeper. A zone can be independent of LAN topology and can be comprised of multiple LAN segments connected using routers or other devices.

2. In AppleTalk, a logical group of network devices. See also ZIP.

Zone Information Protocol

See ZIP.

zone multicast address

Data-link-dependent multicast address at which a node receives the NBP broadcasts directed to its zone. See also NBNS.

zone prefix

A prefix that identifies the addresses to be serviced by a given gatekeeper. Zone prefixes are typically area codes and serve the same purpose as the domain names in the H.323-ID address space.

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