User manual

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forward traffic, however it can learn new MAC addresses.
 Forwarding — Port on this instance is in Forwarding mode. The port
can forward traffic and learn new MAC addresses.
Port Role — Displays the port role, per port per instance, assigned by the
MSTP algorithm in order to provide STP paths. The possible options are:
 Root — Forwarding packets through this interface provides the lowest
cost path to forward packets to the root device.
 Designated — Device is attached to the LAN through this interface.
 Alternate — Interface provides an alternate path to the root device
from the root interface.
 Backup — Interface provides a backup path to the designated port
path toward the Spanning Tree leaves. Backup ports occur only when
two ports are connected in a loop by a point-to-point link. Backup ports
also occur when a LAN has two or more connections connected to a
shared segment.
 Disabled — Interface is not participating in the Spanning Tree.
3.2.3.6 DHCP Relay and Option 82
The Relay Agent Information option (Option82) is inserted by the DHCP relay
agent when forwarding client-originated DHCP packets to a DHCP server
(RFC 3046). Servers recognizing the Relay Agent Information option may use
the information to implement IP address or other parameter assignment
policies. The DHCP Relay can forward the DHCP broadcast packets to a
DHCP server in a different subnet (RFC 1542). So DHCP server can provide
IP addresses to clients spanning multiple subnets instead of deploying a
DHCP server on every subnet.
3.2.3.7 LLDP
LLDP Configuration
Link Layer Discovery Protocol (LLDP) operates on data link layer. It stores and
maintains the information about the local device and the devices directly
connected to it for network administrators to manage networks through NMS
(network management systems).In LLDP, device information is encapsulated
in LLDP PDUs in the form of TLV (meaning type, length, and value) triplets and