Interfacing with a network output..

[bugsy_malone 666]

Bit of an odd question as the title doesnt make a whole lot of sense, but I wondered if there is a way to use the raspberry pi to intercept a network connection and work out whats coming out of it?

To put it in context we have several energy monitors based in our offices which centrally send out data to a third party server somewhere in germany to a third party company, currently that costs us loads every year and it basically gives us graphs and data storage.

So the output is network, but I wondered if there was a way to get a Pi to intercept the output (by plugging the pi into the network port of the other device) and sniff to see what data is coming out?

Cheers

[B.Goode]

Wireshark

[aTao]

If you intercept each device then you would need 1 "inerceptor" per device.
It would be useful to do this for one, but not such a great solution for many.
After analysing the network traffic (assuming its plain text) you can then move your intercept to your building's firewall (you do have one, I hope)
Things that might go wrong:
Obscure or encrypted data
Device wont function without connection to host (you would still have to pay the host)
Probably breaks some agreement with the service provider.

Better solution: replace the whole system with energy monitors as discussed on this forum, a one-off investment in hardware, probably no need for extra computing (your building firewall or server will cope quite easily)

Chat with your energy supplier, they may have cheap/free systems ready to go.

[bugsy_malone 666]

Ultimately I was looking at the fact we already have a system installed, we bought the system but we pay a licence for the front end to continue working.

the system consists of 2 main modules (one ofr each building) then all the monitoring nodes plug into them.

Data wise I'd think its fairly standard because the units also have XD cards (serious what an obscure standard the units were only put in around 2008!) to record data when the networks down and then it uploads when the networks back up.

I'm trying to find out who make the units incase there is a differnt comms method so the network connection could be utilized by the Pi and then feed data to something of our own devising. If could be we only need about 3 Pi's to reroute the system to something entirely in house of my own design.

[aTao]

the system consists of 2 main modules (one ofr each building) then all the monitoring nodes plug into them

What are these plugs?
How do the main modules see the internet, directly via own connection, outside your firewall, or through your firewall?

[bugsy_malone 666]

Well it seems that there are alot of RJ45 connections. I'm not sure if thats just the way its linked together (much like alot of weatherstations that use RJ11 plugs but are just switchs and use that sort of connector).

Each main module connects to the server in germany just via a LAN connection. The boards are similar to the pi in respect to the fact they have an ethernet controller on board.

The company who makes them turns out to be the provider, but we own the equipment, its a company called Dezem.

I'd dearly love to install my own pi based monitoring system, but I dont think the company would approve of this! I am slowly seeing alot of uses for putting the pi to work on our site, but I have to plan to build something that doesnt need a single person to support it, as if I wasnt here they'd be a bit lost if there was a problem.

[BMS Doug]

https://www.dezem.de/en/products

as single measurement device or data logger; measurement results are provided in the form of (encrypted) ASCII telegrams

[bugsy_malone 666]

Well I dont know if our units that are 6 years old are the same.

Alternatively I'd need to make an XD card adaptor so I can turn the Pi into an XD card because I know that the files are like a CSV.