Measuring physical values like temperature or humidity is simple with PCMeasure:
First step: connect a PCMeasure Adapter for 1, 2 or 4 sensors to serial or parallel interface of the PC. For power, the adaptor can use the PC’s USB Port or an external power supply.
Second step: connect a sensor to an RJ 45 port of the adapter. You can do this directly or via your inhouse cable system with RJ 45 plugs for up to 100 meters.
The Windows version of PCMeasure software lets you see your values on the local PC screen. The results are
immediately available over a network. You can access via a web browser, with the free software SNMPView or with a script and MRTG or RRDTools.