Enterasys atx Betriebsanweisung

Introduction

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to an address. In the ATX implementation, the maximum number 
of zones that a router may be configured is 22 ports. Each 
configured zone may be available on any subset of ports.

A Macintosh learns its network address automatically; you don’t 
have to assign addresses. This process is called address acquisition 
and is performed every time a Macintosh enables its datalink, 
either automatically at start-up or using the network control panel. 
This process involves determining a network range from a router 
(or using network 0 if no router is present) and then choosing a 
host number on that range.

If the Macintosh had chosen a host number the last time it was 
rebooted, it tries to use that number again. If it never had a number 
assigned, it picks any unused number. To determine if a number is 
available, the Macintosh sends out AARP probes. If a device 
responds to the probe, a different number is tried until the 
Macintosh finds an unassigned number.

Once the Macintosh has its address, it sends a request to a router to 
determine if a previously used zone name is valid. The router may 
either respond affirmatively or provide the Macintosh with a 
default zone to use. The Macintosh may later change its zone 
residence from the network control panel by asking the router for a 
list of available zones. If no router is present, no zone name is 
assigned.

Routers must also go through the address acquisition process, but 
in a slightly different manner. The process begins each time a link 
becomes active. The router first chooses an address in the start-up 
network range (ff00-fffe) so that it has an address that other routers 
may respond to before it learns its real network range. The ATX 
probes to find its network range; it picks a network range and 
sends out probes to see if it can use that range. Once the router