Bridging Packet Sizes; Displaying Vlan Tagging Statistics - Motorola BSR 2000 Configuration And Management Manual

Release 1.0

Bridging Packet Sizes

The VLAN Tagging feature will accept upstream Ethernet packets from CPEs up to a
maximum size of 1522 bytes from start of the Destination Address to the end of FCS.
A maximum size Ethernet packet with a single "inner" 802.1Q tag added by the
customer CPE is supported. When such packets are bridged onto the trunk mode
network port, the BSR adds an "outer" 802.1Q tag with the configured VLAN for the
CM, increasing the maximum packet size to 1526 bytes.
Likewise, in the downstream direction, the BSR accepts a maximum packet size of
1526 bytes, and will forward a maximum size packet of 1522 bytes to the bridging
CM.
Note: Some CMs may not forward 1522 byte packets with a customer
provided "inner" 802.1Q tag, and instead only forward a maximum size
packet of 1518 bytes. VLAN stacking of maximum size Ethernet packets is
not supported on such cable modems.

Displaying VLAN Tagging Statistics

Use the show bridge vlan command to display receive and transmit statistics for all
VLANs associated with a network bridge port or a specific VLAN, as follows:
MOT#
The following is typical screen output from the show bridge vlan command:
Selected Network Bridge Port: ethernet 0/0
Vlan CM
---- --------------
The show bridge vlan counters command displays statistical counters for all VLANs
or a specific VLAN associated with a network bridge port.
MOT#
where:
526360-001-00 Rev. B
show bridge vlan
2 0000.0000.0065
3 0000.0000.0066
show bridge vlan [counters [<2-4094>]]
MGBI
Configuring VLAN Tagging
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