SMC Networks 7724M/VSW - annexe 1, Руководство пользователя

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Management Guide CLI
TigerAccess™ EE
SMC7824M/VSW 245
default br2 br3
br4 br5
Outer Network
Uplink Port
Untagged packets comes from the uplink ports. The
packets should be forwarded to br3, but the system
cannot know which PVID added to the packet.
Fig. 8.6 Incoming Packets under Layer 2 Shared VLAN Environment (1)
To transmit the untagged packet from uplink port to subscriber, a new VLAN should be
created including all subscriber ports and uplink ports. This makes the uplink ports to rec-
ognize all other ports.
FID helps this packet forwarding. FDB is MAC Address Table that recorded in CPU. FDB
table is made of FID (FDB Identification). Because the same FID is managed in the same
MAC table, it can recognize how to process packet forwarding. If the FID is not same, the
system cannot know the information from MAC table and floods the packets.
default br2 br3
br4 br5
Outer Network
Uplink Port
SWITCH(bridge)# show vlan
u: untagged port, t: tagged port
-----------------------------------------------------------------
| 1 2 3 4
Name( VID| FID) |123456789012345678901234567890123456789012
-----------------------------------------------------------------
default( 1| 6) |u...uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
br2( 2| 6) |.u.....................u..................
br3( 3| 6) |..u....................u..................
br4( 4| 6) |...u...................u..................
br5( 5| 6) |....u..................u..................
br6( 6| 6) |uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
SWITCH(bridge)#
Fig. 8.7 Incoming Packets under Layer 2 Shared VLAN Environment (2)
In conclusion, to use the switch as Layer 2 switch, user should add the uplink port to all
VLANs and create new VLAN including all ports. If the communication between each
VLAN is needed, FID should be same.