Internet-Enabled Calibration: An Analysis of Different Topologies and a Comparison of Two Different Approaches

This paper discusses different network topologies used in Internet-enabled metrology and calibration and explores and compares two different remote calibration systems used by the National Metrology Institutes in England and Norway: the National Physical Laboratory (NPL) and the Justervesenet (JV). The two systems are iGen (NPL) and iMet (JV). The systems both deal with remote calibration of electrical equipment but have substantial architecture differences. In iGen, calibration procedures are downloaded from a server and then locally run at the instrument client, where the operator sits. The client is generic in such a way that it is not dependent on the structure of the measurement procedures. In iMet, two clients can communicate via a public server, and the calibration process may be remotely controlled and monitored. That is, the instruments and the operator may be separated by the Internet.