3com 8807 User Guide
60
NDP C
ONFIGURATION
Introduction to NDP
Neighbor discovery protocol (NDP) is used to discover the information about a
neighbor device directly connected, including the type, software/hardware version,
port connected, ID, port address, and hardware platform of the neighbor device.
neighbor device directly connected, including the type, software/hardware version,
port connected, ID, port address, and hardware platform of the neighbor device.
A device running NDP periodically sends NDP packets to all ports with NDP
enabled while receiving NDP packets from the neighbor device. The device
receiving a NDP packet does not forward it, but maintains an NDP neighbor
information table on the current device and stores the neighbor information
carried in the NDP packets in this table. Besides neighbor device information, NDP
packets contain the information about the aging timer for the NDP information,
which specifies how long the NDP packets will be stored on the receiving device.
enabled while receiving NDP packets from the neighbor device. The device
receiving a NDP packet does not forward it, but maintains an NDP neighbor
information table on the current device and stores the neighbor information
carried in the NDP packets in this table. Besides neighbor device information, NDP
packets contain the information about the aging timer for the NDP information,
which specifies how long the NDP packets will be stored on the receiving device.
If the NDP neighbor information is not updated even after the aging timer for NDP
information expires, the device automatically deletes the entry corresponding to
the NDP information from the NDP neighbor information table. If the neighbor
information received by the device is different from the original information, the
device updates the corresponding entry in the NDP neighbor information table. If
the neighbor information received by the device is the same as the original
information, the device updates only the aging timer in the NDP neighbor
information table.
information expires, the device automatically deletes the entry corresponding to
the NDP information from the NDP neighbor information table. If the neighbor
information received by the device is different from the original information, the
device updates the corresponding entry in the NDP neighbor information table. If
the neighbor information received by the device is the same as the original
information, the device updates only the aging timer in the NDP neighbor
information table.
You can also clear the current NDP information and collect NDP neighbor
information again.
information again.
n
Upon receipt of NDP packets, a switch with NDP disabled directly forwards the
packets to all ports in the same VLAN, while a switch with NDP enabled does not
forward any NDP packet.
packets to all ports in the same VLAN, while a switch with NDP enabled does not
forward any NDP packet.
Introduction to NDP
Configuration Tasks
Configuration Tasks
Table 663 NDP configuration tasks include:
Configuration task
Description Related section
Configure the NDP in the system
Required
Configure the NDP on a port
Required
Configure the aging timer for NDP
information
information
Optional
Section “Configuring the Aging Timer
for NDP Information” “Configuring
the Aging Timer for NDP Information”
for NDP Information” “Configuring
the Aging Timer for NDP Information”
Configure the interval at which NDP
packets are sent
packets are sent
Optional