Allied Telesis AT-S39 User Manual

Page 131

AT-S39 User’s Guide

131

The port assignments for the VLANs are as follows:

This example is similar to the Port-based Example 2 on page 126.
Tagged ports have been added to simplify network implementation and
management.

Port 8 is a tagged port on the top switch. This port has been made a
tagged member of the three VLANs. It is connected to an IEEE 802.1Q-
compliant server, meaning the server can handle frames from multiple
VLANs. Now all three VLANs can access the server without having to
access a router or other interconnection device.

It is important to note that even though the server is receiving and
transmitting frames between more than one VLAN, data remains
separated and secure.

In the example, Port 16 on the top switch and Port 15 on the bottom
switch are tagged ports used to simplify network design. These ports are
tagged members of the Sales and Engineering VLANs. These ports
provide a connection between the different parts of the two VLANs.

In the Port-based Example 2 on page 126, each VLAN required its own
data link between the switches to connect the different parts of the
VLANs. With tagged ports, you can use one data link to carry data traffic
from several VLANs, while still maintaining data separation and security.
The tagged frames, when received by the switch, are delivered only to
those ports that belong to the VLAN from which the tagged frame
originated.

Procedures for user-configured VLANs can be found in Creating Port-
based and Tagged VLANs on page 134.

Switch

Sales VLAN (VID 2)

Engineering VLAN (VID 3)

Production VLAN (VID 4)

Untagged Ports Tagged Ports

AT-8024
(top)

1 to 5, 18
(PVID 2)

8, 16

9 to 11, 20
(PVID 3)

8, 16

21 to 24 (PVID 4) 8

AT-8024
(bottom)

1 to 5 (PVID 2)

19 to 24
(PVID 3)

none