The value to be used as the Authentication Key
whenever the corresponding instance of
nsRip2IfConfAuthType has a value other than
noAuthentication. A modification of the corresponding
instance of nsRip2IfConfAuthType does not modify
the nsRip2IfConfAuthKey value. If a string shorter
than 16 octets is supplied, it will be left-
justified and padded to 16 octets, on the right,
with nulls (0x00).
Reading this object always results in an OCTET
STRING of length zero; authentication may not
be bypassed by reading the MIB object.