The Authentication Key. This object is set according to
the value of the 'vrrpOperAuthType' object
('simpleTextPassword' or 'ipAuthenticationHeader'). If
the length of the value is less than 16 octets, the agent
will left adjust and zero fill to 16 octets. The value of
this object is the same for a given ifIndex.
When read, vrrpOperAuthKey always returns an Octet String
of length zero.
This object is deprecated in the IP Version MIB.