The value of tmnxNtpSysRefId indicates the particular
reference identifier of the local clock. In the case of
stratum 0 (unspecified) or stratum 1 (primary reference source),
this is a four-octet, left-justified,zero-padded ASCII string.
In the case of stratum 2 and greater (secondary reference)
this is the four-octet Internet Address of the peer selected for
synchronization.