The value of tmnxOspfIfAuthKey specifies the authentication key
string. The cleartext password is used as an OSPF Authentication
key when simplePassword security is enabled. This object does not
access any OSPF Cryptographic (e.g. MD5) Authentication Key under
any circumstance.
If the key length is shorter than 8 octets, the agent will left
adjust and zero fill to 8 octets.
Unauthenticated interfaces need no authentication key, and simple
password authentication cannot use a key of more than 8 octets.
Note that the use of simplePassword authentication is NOT recommended
when there is concern regarding attack upon the OSPF system.
This authentication is only sufficient to protect against
accidental misconfigurations because it re-uses cleartext passwords.
[RFC-1704]
When read, tmnxOspfIfAuthKey always returns an Octet String of
length zero.
This object is valid only when tmnxOspfVersion has a value of
'version2'.