User guide

A-32 Cisco 2500 Series Access Server User Guide
Desktop Protocols
AppleTalk Network Numbering
AppleTalk uses a 16-bit number to uniquely identify networks. There are two kinds of
AppleTalk networks, extended and nonextended. Extended networks are used for all LANs
and most WANs.
A single network number, such as 200, identifies a nonextended AppleTalk network.
Nonextended networks can have a maximum of 253 nodes and a single zone name. See the
section “AppleTalk Directory Services” later in this appendix for information on zones.
Nonextended networks are rarely used unless they are required for such support as a
Phase 1 Ethernet (which is now obsolete), X.25, or LocalTalk.
Extended networks allow a cable range that consists of one or more network numbers, such
as 200-201, to be defined and used by nodes on that network.
The access server plays no role in routing packets between network numbers in a range as
all the nodes know the full range of numbers that define the local data link.
Timesaver A good rule of thumb is to have one number in the range for every 50
AppleTalk devices on the LAN. For example, to support 300 devices, use a cable range of
six (such as 201-206).
Figure A-13 shows a sample AppleTalk network numbering and zone naming plan. Zones
are described in the section “AppleTalk Directory Services” later in this appendix.