5 vlan frame type command – ZyXEL Communications IES-708-22A User Manual
Page 288
Chapter 46 IEEE 802.1Q Tagged VLAN Commands
IES-708-22A User’s Guide
288
46.4.4.1 Modify a Static VLAN Table Example
The following is an example of how to modify a static VLAN table.
46.4.4.2 Forwarding Process Example
Tagged Frames
1 First the IES-708-22A checks the VLAN ID (VID) of tagged frames or assigns
temporary VIDs to untagged frames (see
2 The IES-708-22A checks the frame’s source MAC address against the MAC filter.
3 The IES-708-22A then checks the VID in a frame’s tag against the SVLAN table.
4 The IES-708-22A notes what the SVLAN table says (that is, the SVLAN tells the IES-
708-22A whether or not to forward a frame and if the forwarded frames should have a
tag).
5 Frames might be dropped if they are sent to a CPE (customer premises equipment) DSL
device that does not accept tagged frames.
Untagged Frames
1 An untagged frame comes in from the LAN.
2 The IES-708-22A checks the frame’s source MAC address against the MAC filter.
3 The IES-708-22A checks the PVID table and assigns a VID and IEEE 802.1Q priority.
4 The IES-708-22A ignores the port from which the frame came, because the IES-708-
22A does not send a frame to the port from which it came. The IES-708-22A also does
not forward frames to “forbidden” ports.
5 If after looking at the SVLAN, the IES-708-22A does not have any ports to which it will
send the frame, it drops the frame.
46.4.5 VLAN Frame Type Command
Syntax:
ras> switch vlan frametype <portlist> <all|tag>
where
This command sets the specified DSL ports to accept VLAN tagged Ethernet frames, or both
tagged and untagged Ethernet frames.
ras> switch vlan set 2000 1:FU
ras> switch vlan set 2001 2:FU
<portlist>
=
You can specify a single DSL port <1>, all DSL ports <*> or a
list of DSL ports <1,3>. You can also include a range of DSL
ports <1,5,6~8>.
<all|tag>
=
Use
tag
to have the specified port(s) accept only incoming
Ethernet frames that have a VLAN tag.
Use
all
to have the specified port(s) accept both tagged and
untagged incoming Ethernet frames.