Topology Discovery; Description Of Topology Discovery - Hirschmann RS20 User Manual

Operation diagnosis

9.8 Topology discovery

9.8.1 Description of topology discovery

IEEE 802.1AB describes the Link Layer Discovery Protocol (LLDP). LLDP
enables the user to have automatic topology recognition for his LAN.
A device with active LLDP
sends its own connection and management information to neighboring
devices of the shared LAN, once these devices have also activated LLDP.
receives connection and management information from neighboring
devices of the shared LAN, once these devices have also activated LLDP.
sets up a management information schema and object definition for
saving connection information of neighboring devices with active LLDP.
A central element of the connection information is the exact, unique ID of a
connection point: MSAP (MAC Service Access Point). This is made up of a
device ID unique within the network and a port ID unique for this device.
Content of the connection and management information:
Chassis ID (its MAC address)
Port ID (its port MAC address)
Description of the port
System name
System description
Supported system capabilities (e.g. router = 14 or switch = 4)
Currently activated system capabilities
Interface ID of the management address
VLAN ID of the port
Status of the autonegotiation at the port
Medium, half and full duplex settings and speed setting of the port
Information about whether a redundancy protocol is switched on at the
port, and which one (STP, RSTP, HIPER-Ring, Ring Coupling, Dual
Homing).
Information about the VLANs of which the port is a member (VLAN ID and
VLAN name).
Basic Configuration L2P
Release 4.2 07/08
9.8 Topology discovery
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