ZyXEL Communications Dimension ES-3124, Руководство пользователя

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Dimension ES-3124 Ethernet Switch
IEEE 802.1Q Tagged VLAN 30-7
<ADCTL> = This is the registrar administration control flag.
Valid parameters = [
fixed
,
forbidden
,
normal
].
Enter
fixed
to register a
<port #>
to the static VLAN table with
<vid>
.
Enter
normal
to confirm registration of the
<port #>
to the static VLAN
table with
<vid>
.
Enter
forbidden
to block a
<port #>
from joining the static VLAN table
with
<vid>
.
<TAGCTL> =
This is the tag control flag. Valid parameters = [
tag
|
untag
].
Enter
tag
to tag outgoing frames.
Enter
untag
to send outgoing frames without a tag.
This command adds or modifies an entry in the static VLAN table. Display your configuration by using the
sys
sw vlan1q
svlan list
command. An example of a configuration is shown next.
Modify a Static VLAN Table Example
The following is an example of how to modify a static VLAN table.
Figure 30-12 Modifying the Static VLAN Example
Forwarding Process Example
Tagged Frames
Step 1.
First the switch checks the VLAN ID (VID) of tagged frames or assigns temporary VIDs to untagged
frames (see
Section 30.4.7 ).
Step 2.
The switch then checks the VID in a frame’s tag against the SVLAN table.
Step 3.
The switch notes what the SVLAN table says (that is, the SVLAN tells the switch whether or not to
forward a frame and if the forwarded frames should have tags).
Step 4.
Then the switch applies the port filter to finish the forwarding decision. This means that frames may be
dropped even if the SVLAN says to forward them. Frames might also be dropped if they are sent to a
CPE (customer premises equipment) DSL device that does not accept tagged frames.
Untagged Frames
Step 1.
An untagged frame comes in from the LAN.
Step 2.
The switch checks the PVID table and assigns a temporary VID of 1.
Step 3.
The switch ignores the port from which the frame came, because the switch does not send a frame to the
port from which it came. The switch also does not forward frames to “forbidden” ports.
Step 4.
If after looking at the SVLAN, the switch does not have any ports to which it will send the frame, it
won’t check the port filter.
1. ES-3124> sys sw vlan1q svlan setentry 2000 1 fixed tag
2. ES-3124> sys sw vlan1q svlan setentry 2001 2 fixed tag