User`s guide

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Introduction
1.8.7 Appletalk Routing
AppleTalk routing allows end-nodes to send packets to and receive
packets from other end-nodes through the use of AppleTalk Phase
2 protocol. The ATX stores a table of routing information it learns
through Routing Table Maintenance Protocol (RTMP) packets sent
out by other routers. The ATX also sends out RTMP packets to let
other routers know of the routes it has learned. By storing the
RTMP packets, the ATX knows where to forward packets it
receives.
AppleTalk addressing
An AppleTalk address consists of 16 bits of network number, 8 bits
of host number, and a zone name.
In AppleTalk routing, a logical network is defined by a contiguous
set of network numbers. Routes are therefore generated for a
network range instead of to a single network number. Macintoshes
know both their address (network number/host number pair) and
their network range. A router is not needed to send a packet to a
different network number in the same range.
AppleTalk zones
The concept of AppleTalk zones allows Macintoshes to be grouped
together logically, independent of network address. Each
AppleTalk device such as a Macintosh or a printer belongs only to
one zone. There may be more than one zone on a network and a
zone may be available on many networks.
In order to establish a session with a network device such as a file
server or a printer, a user selects a zone name from the list under
their network connection in the Network dialog box in the Control
Panel. They would then go to the Chooser on their Macintosh
desktop and select a device from the list available. For example,
you might select the zone Engineering and the device Laser Printer.
Underlying protocols then map this Network Visible Entity name