AutoTracker VLANs
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Devices that Generate a Secondary Traffic Type

Source devices sometimes generate more than one traffic type; for example, a device could

generate IP traffic primarily but also generate a secondary stream of AppleTalk. When a

device generates secondary traffic that does not match any existing VLAN policy, that traffic is

grouped into the primary VLAN of which the device is a member.

To continue the example, if a device generates both IP and AppleTalk, and both an IP VLAN

and an AppleTalk VLAN exist, that device is made a member of both VLANs and no problem

occurs. If, however, an AppleTalk VLAN does not exist, all traffic from that device is grouped

into the existing VLAN of which the device is a member – in this example, the IP VLAN. This

can cause communication problems, as explained below. For this reason, it is advisable to
create VLANs that accommodate all known network traffic.
Omni Switch/Router
12345678
123456
In this example Device A is
assigned to default VLAN #1
because it does not match any
existing VLAN policy.
Devices B and C are assigned to
VLAN 2 because they generate IP
traffic. The secondary AppleTalk
traffic Device C generates is also
grouped into VLAN 2, since the
AppleTalk traffic does not match
any existing VLAN policy.
The result is that Devices A and
C are unable to communicate.
Creation of an AppleTalk proto-
col VLAN solves this problem. If
an AppleTalk VLAN exists,
Device A will be assigned to it
and removed from Default VLAN
#1. Device C will be assigned to
both the IP VLAN and the Apple-
Talk VLAN. Devices A and C can
then communicate.
VLAN 1
(default VLAN #1)
no policies allowed
VLAN 2
IP protocol VLAN
Group 2
Assignment of devices to
default VLAN when they do not
match any policies is enabled.
Device B
IP traffic only
Device A
AppleTalk traffic only
Device C
IP and AppleTalk
traffic