Hi!
I'm new here, but I have used resources from the project for a while.
I'm planning to make an addon or a new program with less comunication overhead than OemGateway HTTP request system, since I'm using EmonCMS for monitoring some system via GPRS, and I need to reduce data traffic to minimum, since I have to pay per Kb.
I'm planning to use CoAP protocol:
Using the CoAPthon, Python implementation:
https://github.com/Tanganelli/CoAPthon
Have anyone tried something like this?
Have a nice day!!!!
Re: OemGateway with less overhead
Have you tought on gzip compression on http, easy configured on the web server ?
Re: OemGateway with less overhead
I am already doing this (kind of) using MQTT. I have an MQTT broker which my Emon nodes publish to, and then a script running on a 24/7 server which monitors the MQTT feeds and forwards them to EmonCMS using the standard HTTP API.
Check out the emoncms target in mqttwarn (https://github.com/jpmens/mqttwarn#emoncms) for details of the forwarding script.
Re: OemGateway with less overhead
@chaveiro: do you mean gzip compression on the client side, server side or both?
Is emoncms.org already configured to send gzip request?
Thanks
Walter
Re: OemGateway with less overhead
Forget about my questions! I don't need to download/upload anything from/to EmonCMS that would require a compression.
I think that the server responses count more in term of data traffic than the data I upload to EmonCMS. Maybe the length of these responses could be reduced. However, I quickly checked with the Mozilla HttpRequester extension and they look "fine" to me. I have seen other servers that send back much more data.
For those interested, I have done a few tests with a UMTS/3G USB stick (http://openenergymonitor.org/emon/node/11003) and I was reaching 302 MB/month with 10 keys every 15 secs.
Walter
Re: OemGateway with less overhead
Hi!
Sumnerboy, I'll give a look to your work ;)
I'm progressing with the CoAP implementation, since it uses UDP, it han't got any reply needs, and also has less overhead than UDP.
Currently I have reduced the data payload from around a 1kb for query to less than 200 bytes.
The next step is to modify OemGateway for adding a Buffer module that works via CoAP. I'll keep you informed.
Re: OemGateway with less overhead
If you would be interested in upgrading to emonHub I would be happy to help you with a CoAP reporter (called dispatchers in OEMG). emonHub superseeds OEMG and adds extra reliability and flexibility to what was a superb software. Plus it's actively supported and developed.
I did look at this when you first posted and found it interesting, although I wasn't sure of the demand for it due to the MQTT following also providing a method with less overhead. I saw the server implementation as the harder part and wasn't really able to assist with that but the client looked relatively simple (famous last words) and so if you want some assistance with an emonHub implementation let me know.
Paul