Class of Service
147
ATTENTION
If your host devices do not support GVRP, then configure static or untagged
VLANs for the switch ports connected to these devices. You can still enable
GVRP on these edge switches, as well as on the core switches in the network.
Tagged and untagged frames
Ports on the switch can be assigned to multiple tagged VLANs. Ports on
the BES50FE-12/24T PWR can be assigned to multiple untagged VLANs,
however, ports on the BES50GE-12/24T PWR can be assigned to only
one untagged VLAN. Each port on the switch is capable of passing tagged
or untagged frames.
For BES50GE-12/24T, if a port is already an untagged member of VLAN 1,
making it an untagged member of VLAN 2 disassociates it from VLAN 1.
The same result happens from VLAN 2 to VLAN 1.
When forwarding a frame from the switch along a path that contains
any VLAN-aware devices, the switch should include VLAN tags. When
forwarding a frame from the switch along a path that does not contain
any VLAN-aware devices (including the destination host), the switch must
first strip off the VLAN tag before forwarding the frame. When the switch
receives a tagged frame, it passes this frame on to the VLANs indicated by
the frame tag. However, when the switch receives an untagged frame from
a VLAN-unaware device, it first decides where to forward the frame, and
then it inserts a VLAN tag reflecting the ingress port default VID.
GVRP (global setting)
GARP VLAN Registration Protocol (GVRP) defines a way for switches to
exchange VLAN information to register VLAN members on ports across the
network. VLANs are dynamically configured based on join messages issued
by host devices and propagated throughout the network. GVRP must be
enabled to permit automatic VLAN registration and to support VLANs that
extend beyond the local switch.
Link Layer Discovery Protocol
Link Layer Discovery Protocol (LLDP) allows devices on the network to
share information about themselves for simplified troubleshooting, enhanced
network management, and maintaining an accurate network topology.
LLDP-capable devices periodically transmit information in messages called
Type Length Value (TLV) fields to neighbor devices.
Class of Service
With Class of Service (CoS), you can specify which data packets have
greater precedence when traffic is buffered in the switch due to congestion.
The switch supports CoS with four priority queues for each port. Data
SMB
Using the Nortel Business Ethernet Switch 50 Series
NN47924-301
01.01
Standard
1.00
October 2006
Copyright © 2006, Nortel Networks
Nortel Networks Confidential
.
Summary of Contents for BES50FE-12T PWR
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