MediaGateway
User Manual
61
3.6.4
Important VLAN tagging rules
default VLAN ID:
If tagging is activated, every frame which enters a switch on a specific port, is
tagged by the VLAN ID which is configured in field
default VLAN ID
on this specific
port.
The MediaGateway does never overwrite any VLAN tags. It means a frame already
tagged before entering a switch of the MediaGateway’s switch doesn’t change its
VLAN tag.
Both rules are valid for both VLAN tags and in both VLAN tagging modes
(single/double).
VLAN membership
This field is only checking outgoing traffic!
In double-tagging mode:
Only the outerVLAN tag is checked and compared to the VLAN ID list configured in
this field for the specific port.
In single-tagging mode:
The (inner)VLAN tag is checked and compared to the VLAN ID list configured in
this field for the specific port.
If a port is membership of a specific VLAN ID, frames tagged with this VLAN ID
(single Tagging) or only outerVLAN ID (double tagging) can leave the switch on this
specific port.
egress VID remarking:
(only double-tagging mode)
This function affects only outgoing traffic
remove
means removing the inner/outer VLAN tag
normalized
is sending the frames with inner/outer VLAN tag
as received
is sending the frames as the frames came into the current switch. For
example:
Both egress VID remarking are set to
as received
The frame comes into switch 1 on port 3 (S1-P3) and has no outerVLAN-Tag but
already an innerVLAN tag and should leave the Switch on port 8 (S1-P8). In this
case the following will happen:
-
The frame gets the
default VLAN id
from port S1-P3 but only the outerVLAN-
tag, the innerVLAN tag is already there.
-
VLAN-membership
of S1-P8 has the same VLAN ID configured as the
default
VLAN-ID
on S1-P3. => Frame will leave here the Switch 1
-
The frame will be sent from Switch 1 to Switch 2 with innerVLAN tag, because
the frame had already the innerVLAN tag while entering the Switch 1
