3Com 5500-SI Configuration Manual page 92

92 C 5: DLDP C
HAPTER ONFIGURATION
2 DLDP analyzes and processes received packets as follows:
In authentication mode, DLDP authenticates the packets on the port, and discards
n
those do not pass the authentication.
DLDP processes the received DLDP packets as follows:
n
Table 75
Process received DLDP packets
Packet type Processing procedure
Advertisement Extracts
packet neighbor
information
Flush packet Deletes the neighbor entry from the local device
Probe packet Sends echo
packets
containing both
neighbor and its
own
information to
the peer
Echo packet Checks whether
the local device
is in probe
status
3 If no echo packet is received from the neighbor, DLDP performs the following
processing
:Refer to Table 76 to process w
Table 76
Processing when no echo packet received from the neighbor
No Echo packet
received from the
neighbor
In normal mode, no
echo packet is received
when the echo waiting
timer expires
In enhanced mode, no
echo packet is received
when the enhanced
timer expires
If this neighbor entry does not exist on the local device, DLDP
creates the neighbor entry, enables the entry aging timer,
and turns to probe status.
If the neighbor entry already exists on the local device, DLDP
resets the entry aging timer.
Creates the neighbor entry if this neighbor entry does not
exist on the local device.
If the neighbor entry already exists on the local device,
refreshes the entry aging timer.
No Discards this echo packet
Yes Checks whether
neighbor information
in the packet is the
same as that on the
local device
hen no echo packet received from the neighbor.
Processing procedure
DLDP turns into disable status. It outputs log and tracking information,
sends flush packets. Depending on the user-defined DLDP down mode,
DLDP disables the local port automatically or prompt the user to disable
the port manually. DLDP sends the RSY message and deletes the
neighbor entry.
No Discards this echo
packet
Yes Sets the neighbor flag
bit to bidirectional
If all neighbors are in
bidirectional
communication state,
DLDP turns from
probe status to
advertisement status,
and sets the echo
waiting timer to 0.