The value of tmnxNtpPeersAuthKeyId specifies the key-id of
the authentication key and its authentication type used by this
node to receive and transmit NTP packets to and from
an NTP server and peers. When an NTP packet is received
by this node both authentication key and authentication type
must be valid otherwise the packet will be rejected and an
tmnxNtpAuthMismatch notification generated. When the value of
tmnxNtpPeersAuthKeyId has a value of '0', no authentication
is performed.