HP A5120 EI Configuration Manual page 44

 Non-authentication:
The sending side sets the Authentication field and the Authentication type field of DLDP packets

to 0.
The receiving side checks the values of the two fields in received DLDP packets, and drops any

packets where the two fields conflict with the corresponding local configuration.
Plain text authentication:

Before sending a DLDP packet, the sending side sets the Authentication field to the password

configured in plain text and sets the Authentication type field to 1.
The receiving side checks the values of the two fields in received DLDP packets and drops any

packets where the two fields conflict with the corresponding local configuration.
MD5 authentication:

Before sending a packet, the sending side encrypts the user configured password using MD5

algorithm, assigns the digest to the Authentication field, and sets the Authentication type field to
2.
The receiving side checks the values of the two fields in received DLDP packets, and drops any

packets where the two fields conflict with the corresponding local configuration.
DLDP processes
On a DLDP-enabled link that is in up state, DLDP sends DLDP packets to the peer device and
1.
processes the DLDP packets received from the peer device. DLDP packets sent vary with DLDP
states.
Table 13 DLDP packet types and DLDP states
DLDP state
Active
Advertisement
Probe
Disable
NOTE:
A switch sends Flush packets when it transits to the Initial state from the Active, Advertisement, Probe,
or DelayDown state but does not send them when it transits to the Initial state from Inactive or Disable
state.
A received DLDP packet is processed with the following methods.
2.
 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 to send Advertisement packets it carries conflicts
with the corresponding local setting.
Other processes are as shown in

Table 14 Procedures for processing different types of DLDP packets received
Packet type
Advertisement
packet with RSY
tag
Type of DLDP packets sent
Advertisement packet with RSY tag
Normal Advertisement packet
Probe packet
Disable packet and then RecoverProbe packet
Table
Processing procedure
If the corresponding neighbor entry does not exist, creates the
Retrieves the
neighbor entry, triggers the Entry timer, and transits to Probe
neighbor information
state.
14.
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