3Com 4510G Configuration Manual page 811

When a device transits from a DLDP state other than Inactive state or Disable state to Initial state, it
sends Flush packets.
2) A received DLDP packet is processed as follows.
In any of the three authentication modes, the packet is dropped if it fails to pass the authentication.
The packet is dropped if the setting of the interval for sending Advertisement packets it carries
conflicts with the corresponding local setting.
Other processes.
Table 4-5 Procedures for processing different types of DLDP packets
Packet type
Advertisement Retrieving the
packet with RSY neighbor
tag information.
Normal
Retrieves the
Advertisement
neighbor
information.
packet
Determines
whether or not the
Flush packet
local port is in
Disable state.
Retrieves the
Probe packet neighbor
information.
Retrieves the
Echo packet neighbor
information.
Check to see if the
Disable packet local port is in
Disable state.
Processing procedure
If the corresponding neighbor entry does not exist,
creates the neighbor entry, triggers the Entry timer, and
transits to Probe state.
If the corresponding neighbor entry already exists, resets
the Entry timer and transits to Probe state.
If the corresponding neighbor entry does not exist,
creates the neighbor entry, triggers the Entry timer, and
transits to Probe state.
If the corresponding neighbor entry already exists, resets
the Entry timer.
If yes, no process is performed.
If not, removes the corresponding neighbor entry (if any).
If the corresponding neighbor entry does not exist,
creates the neighbor entry, transits to Probe state, and
returns Echo packets.
If the corresponding neighbor entry already exists, resets
the Entry timer and returns Echo packets.
If the corresponding neighbor entry does not exist,
creates the neighbor entry, triggers the Entry timer, and
transits to Probe state.
If the neighbor information it carries
conflicts with the corresponding locally
maintained neighbor entry, drops the
The
packet.
correspondi
ng neighbor
Otherwise, sets the flag of the neighbor
entry
as two-way connected. In addition, if the
already
flags of all the neighbors are two-way
exists
connected, the device transits from Probe
state to Advertisement state and disables
the Echo timer.
If yes, no process is performed.
If not, the local port transits to Disable state.
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