John Leong <johnleong@research.bell-labs.com> writes:

Curious if any operator uses, or have interest in using, out of band network (e.g. modem, wireless etc.) for remote equipment (routers, switches, HVAC etc.) monitoring over and above doing it in band on the Internet.

In past jobs, we have done this for both administration and some monitoring. For administration, we just used an old Annex3 terminal server as a serial connection mux. We plugged up to 64 serial cables into the consoles of various devices, and connected a modem to one of those serial cables. That worked really well. For monitoring, a team that I worked with had a machine that monitored the network and had a connection to a phone line to issue pages when things broke. I think these are both fairly common setups. Hope this helps, ------ScottG.