EDS-518A Series User’s Manual
Featured Functions
3-36
y
Access Port:
The port connects to a single device that is not tagged. The user must define the
default port PVID that determines to which VLAN the device belongs. Once the ingress
packet of this Access Port egresses to another Trunk Port (the port needs all packets to carry
tag information), EDS-518A will insert this PVID into this packet to help the next 802.1Q
VLAN switch recognize it.
y
Trunk Port:
The port connects to a LAN that consists of untagged devices/tagged devices
and/or switches and hubs. In general, the traffic of the Trunk Port must have a Tag. Users can
also assign PVID to a Trunk Port. The untagged packet on the Trunk Port will be assigned the
port default PVID as its VID.
The following section illustrates how to use these ports to set up different applications.
Sample Applications of VLANs using MOXA EDS-518A
Port 3 (Trunk Port, PVID 1)
VLAN 5 Untagged Device
VLAN 3 Untagged
Device
VLAN 4 Untagged
Device
VLAN 5 Untagged Device
VLAN 2 Untagged
Device
VLAN 4 Tagged Device, VID 4
VLAN 3 Tagged Device, VID 3
VLAN 2 Untagged
Device
VLAN 2 Untagged
Device
Device A
Switch A
Switch B
Device C
Device B
Device D
Device E
Device F
Device G
Device H
Device I
Port 1 (Access Port
PVID 5)
Port 7 (Access Port
PVID 4)
Port 5 (Access Port
PVID 3)
Port 4 (Access
Port PVID 2)
Port 2 (Trunk Port PVID 2,
Fixed VLAN (Tagged)=3,4)
Port 6 (Access Port PVID 5)
HUB
In this application,
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Port 1 connects a single untagged device and assigns it to VLAN 5; it should be configured as
“Access Port” with PVID 5.
y
Port 2 connects a LAN with two untagged devices belonging to VLAN 2. One tagged device
with VID 3 and one tagged device with VID 4. It should be configured as “Trunk Port” with
PVID 2 for untagged device and Fixed VLAN (Tagged) with 3 and 4 for tagged device. Since
each port can only have one unique PVID, all untagged devices on the same port can only
belong to the same VLAN.
y
Port 3 connects with another switch. It should be configured as “Trunk Port.” GVRP protocol
will be used through the Trunk Port.
y
Port 4 connects a single untagged device and assigns it to VLAN 2; it should be configured as
“Access Port” with PVID 2.
y
Port 5 connects a single untagged device and assigns it to VLAN 3; it should be configured as
“Access Port” with PVID 3.