Motorola BSR 2000, Configuration And Management Manual

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BSR 2000 Configuration and Management Guide Release 1.0
13-12 MGBI 526360-001-00 Rev. B
3. Use the encapsulation dot1q command to configure a routed VLAN on the
BSR’s Ethernet interface, as follows:
MOT(config-if)#
encapsulation dot1q <
2-4094
>
where:
2-4094
specifies the VLAN ID for routed traffic.
4. Use the no encapsulation dot1q command to disable VLAN tagged routing on
the BSR’s Ethernet interface, as follows:
MOT(config-if)#
no encapsulation dot1q <
2-4094
>
Configuring the External L2/L3 Switch
The VLAN Tagging feature of the BSR performs point-to-point forwarding from one
CM to one IEEE 802.1Q VLAN. When CPE traffic from multiple cable modems
belonging to the same enterprise customer must be bridged together, an L2 switch
external to the BSR must perform "inter-VLAN" bridging of the different "per-CM"
VLANs into a single "per-Customer" VLAN.
One way to perform inter-VLAN bridging is to configure a sub-interface in the
external L2 switch for each per-CM VLAN, and then bridge each of the sub-interfaces
to the same bridge group. An example of this is depicted below.
In this example, the external Cisco router is configured to connect to the BSR with the
following configuration:
interface Ethernet 0/0.1
encapsulation dot1q 17
bridge group 100
interface Ethernet 0/0.2
encapsulation dot1q 18
bridge group 100
Note: The encapsulation dot1q command is applicable only if the
corresponding Ethernet interface is configured with bridge mode trunk
command.
VLAN ID 1 is reserved for use by the attached Layer 2 switch/router for
management purposes and as the default "native" VLAN for that equipment.
VLAN ID 1 may not be configured on the BSR for Ethernet port tagged
routing or for cable modem Layer 2 bridging.