Cabletron Systems CSX1000 - Manual (Page 309)

Workgroup Remote Access Switch 309
C ONFIGURING A PPLE T ALK R OUTING
AppleTalk Ports
T HE Z ONE C ONCEPT
A zone is a logical group of nodes on an internet, much like the concept of subnetting with the
world of IP. Within the framework of Phase 2 the logical assignment of zones is limited to 255 zone
names for a network. Each name can be configured to represent a logical group within that
respective internet. An example would be zone 1=Marketing, zone 2=Engineering etc. By
configuring an AppleTalk router with logical zones you establish a mode of efficient data transport
that acts much the same as IP with multiple subnets.
Although the concept of zones are the same as IP subnets, zone names do not have to be configured
to encompass nodes with one physical location. Zones can be configured to incorporate nodes that
are geographically diverse. Within this framework the dynamic address assignment allows the
user to view all zones that are configured, and have been set up to give that particular user access
to these zones. Thus, with this framework, a user can select the zone in which they want to be a part
of for that particular task. Later, at a user’s discretion, they may choose to be part of a different zone.
If a user does not choose to associate with a respective zone, in a multi-zone internet a default zone
is configured and all non-selective nodes will be associated with the default zone until a choice is
made.
With the above in mind, continuing on with the ability to set up zones with non-local nodes, the
network has an associated zone multicast address. When a device chooses a zone, it registers itself to
receive packets sent to the specific zone-multicast address associated with that zone. Zone-
multicast addresses are used to significantly reduce the overhead associated with dynamic naming.
A PPLE T ALK R EMOTE LAN
Overview
An AppleTalk WAN (Remote LAN) port connects remote bridge devices to other AppleTalk router
ports. The AppleTalk router treats all bridge devices connected to the Remote LAN as if they were
on an Ethernet LAN segment. That is, the CyberSWITCH emulates an Ethernet medium over the
series of ISDN point-to-point connections. The AppleTalk router encapsulates AppleTalk data for
the Remote LAN port in Ethernet packets and forwards the data to the remote bridges.
If the Remote LAN only has Macs connected to it, these Macs assume the AppleTalk network number/
range assigned to the Remote LAN port. For these simple remote networks, you are not required
to configure an AppleTalk network number for the remote bridge device. When the remote bridge
connects, it is associated with the first configured AppleTalk Remote LAN port.
If the Remote LAN has both AppleTalk routers and Macs connected to it, the Macs assume the AppleTalk
network number/range of the remote AppleTalk routers. For these remote networks, the
AppleTalk Remote LAN network number/range must correspond to that of the remote AppleTalk
router. In this case, you should configure an explicit AppleTalk network number for the remote
bridge device so that the same network number is applied to the Remote LAN each time it connects.
When the remote bridge connects, it is explicitly associated with the AppleTalk Remote LAN port
that corresponds to the AppleTalk network number in the
bridge device table entry .
Remote LAN ports differ from LAN ports on the handling of a configured network number/range
versus a learned network number/range. LAN ports are by default soft seeds when a network
number/range is configured. This means that if an RTMP packet is received with a different
network number/range than configured, the LAN port assumes the RTMP packet contains the