VigorSwitch G1260 User’s Guide
35
untagged for a transmitted packet. When a packet is transmitted out,
the VLAN bridge checks the port’s egress list. If the VLAN of the
packet is on the egress list of the port on which the packet transmits
out, the packet will be transmitted with the priority accordingly. If
enabled, an egress port will transmit out a tagged packet if the port is
connected to a 802.1Q-compliant device.
If an egress port is connected to a non-802.1Q device or an end
station, VLAN bridge must transmit out an untagged packet, i.e. the
tag has been stripped off in an egress port. Egress rule can be set by
per port.
Independent VLAN Learning (IVL): It specifies the mode how to learn MAC address. For
a specified VLAN, it will use an independent filtering database (FID)
to learn or look up the membership information of the VLAN and
decide where to go.
Shared VLAN Learning (SVL): It specifies the mode how to learn MAC address. In this
mode, some VLAN or all VLANs use the same filtering database
storing the membership information of the VLAN to learn or look up
the membership information of the VLAN. In 24-Port GbE Web
Smart Switch, you can choose a VID for sharing filtering database in
Shared VID field if you wish to use the existed filtering database.
For a specified VLAN, when a MAC address is learned by a switch,
VLAN will use this formation to make forwarding decision.
Filtering Database: Referred to as FID. It can provide the information where the packet
will be sent to. Filtering database will supply the outgoing port
according to the request from forwarding process with VID and DA.
When a packet is received, if it has a non-zero VID, then FID will
offer the associated outgoing ports information to the packet.
In SVL, VLANs use the same Filtering Database. In IVL, VLANs
use different FIDs. Any VID can be assigned to the same FID by
administrator.
H
H
o
o
w
w
d
d
o
o
e
e
s
s
a
a
T
T
a
a
g
g
g
g
e
e
d
d
V
V
L
L
A
A
N
N
w
w
o
o
r
r
k
k
?
?
If the ingress filtering is enabled and when a packet is received, VLAN bridge will first
check if the VID of the packet presents.
1.)
If the packet has a non-zero VID, VLAN bridge will apply this VID as the VLAN ID
of the packet in the network.
2.)
For a packet with null tag or no VLAN tag, if VLAN bridge provides rules to decide its
VID, then apply this VID to the packet.
If VLAN bridge does not support any rule for VID, then apply the PVID of the port to the
packet which came from that port. VLAN bridge checks to see if the ingress port and the
received packet are on the same VLAN. If not, drops it. If yes, forwards it to the associated
ports. Meanwhile, this VLAN must be applied to the egress port, or the packet will be
dropped.
If ingress filtering is disabled, VLAN bridge will only check the MAC address table to see
if the destination VLAN exists. If VLAN does not exist, then drop the packet, and if both
DA and VLAN do not exist, forwards the packet. If just knows VLAN existed, then floods
the packet to all the ports the VLAN covers.
Содержание VigorSwitch G1260
Страница 1: ...i ...
Страница 24: ...VigorSwitch G1260 User s Guide 18 This page is left blank ...
Страница 44: ...VigorSwitch G1260 User s Guide 38 ...
Страница 84: ...VigorSwitch G1260 User s Guide 78 This page is left blank ...
