ZyXEL Communications IES-612-51A User Manual

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Chapter 45 IEEE 802.1Q Tagged VLAN Commands
IES-612-51A User’s Guide
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45.4.4.1  Modify a Static VLAN Table Example
The following is an example of how to modify a static VLAN table.
45.4.4.2  Forwarding Process Example
Tagged Frames 
First the IES-612-51A checks the VLAN ID (VID) of tagged frames or assigns 
temporary VIDs to untagged frames (see 
The IES-612-51A checks the frame’s source MAC address against the MAC filter.
The IES-612-51A then checks the VID in a frame’s tag against the SVLAN table. 
The IES-612-51A notes what the SVLAN table says (that is, the SVLAN tells the IES-
612-51A whether or not to forward a frame and if the forwarded frames should have a 
tag). 
Frames might be dropped if they are sent to a CPE (customer premises equipment) DSL 
device that does not accept tagged frames.
Untagged Frames
An untagged frame comes in from the LAN. 
The IES-612-51A checks the frame’s source MAC address against the MAC filter.
The IES-612-51A checks the PVID table and assigns a VID and IEEE 802.1Q priority. 
The IES-612-51A ignores the port from which the frame came, because the IES-612-
51A does not send a frame to the port from which it came. The IES-612-51A also does 
not forward frames to “forbidden” ports. 
If after looking at the SVLAN, the IES-612-51A does not have any ports to which it will 
send the frame, it drops the frame. 
45.4.5  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.
Figure 153   Modifying the Static VLAN Example
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 <1,5,6~10>.
<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.