check out the BarioNet device at:
http://www.barix.com/en/datasheets/P...onet%20V17.pdf

It is an SNMP supported programmable device with RS232, RS485 ports.
Low cost; list is $295 I think.
Can also be used for Server Rack environment monitoring: temp,
humidity, water, etc, as well as Remote control as it has 4 digital
outputs and a couple of 5A relays. (all SNMP commandable)

Good luck!