Has anyone had any experience with using MQTT on really slow internet speeds? Like 500 kbps? It would be 50 to 100 tags but only 10 to 20 that would be changing every few seconds.
MQTT was designed for low-bandwidth networks, so I would assume that it would be fine. The level of QoS (quality of service) would probably affect the network capacity.
As @dhkayes117 stated, this is exactly what MQTT was designed for. You can configure the local polling rate faster than the MQTT publishing rate, so that if you’re logging historical data, you’ll have your full local polling resolution, but then the live data only updates every 5-10 seconds (or whatever you set it up for) when MQTT pushes all the data it’s collected since the last push. I’d also recommend setting up tag aliases and gzip compression in the MQTT transmission module to reduce bandwidth usage if you’re really concerned, but most of the time the largest publish will be the BIRTH at the initial connection when MQTT pushes all of the tags and current values at once because after that it only pushes tag values that have changed (report by exception).
Also, keep in mind that if you’re doing read/write to the remote device, the MQTT publishing rate isn’t restricting how fast you can push values to the remote device. Whenever a tag value is changed, it is immediately pushed to the client over the same connection, and only the feedback may be delayed getting pushed back to the central server. (Hopefully that makes sense). In other words, if I have a pushbutton on the HMI that starts/stops a motor, as soon as I push the button on the server side, it pushes that value to start the motor immediately, but on the remote side if you’re only publishing data every 30 seconds, it could take up to 30 seconds to see the feedback change (I say up to, because if the next publish is in 2 seconds, it would only take 2 seconds until you see it instead of the full 30 seconds).
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Now a days with 4G and 5G and fiber net being the norm for Internet, bandwidth in KBs is quite unheard of! Under what circumstances do you get such low speed internet speed even if you want to get, as the 2.5 and 3G networks are phased out everywhere? Of course 20 , 30 years ago with dialup and DSL modems and 2.5G and 3G networks the speed was specified in KBs (I remember 64KB bandwidth on a dialup modem was considered huge!)
I’m looking into a satellite option for when we operate our mobile equipment in areas where cellular isn’t available at all. I have found some faster rates but the antenna for those faster rates costs more than the entire automated equipment we are operating.
I have found some antennas with pricing below $10K (which is a lot cheaper than the $50K options I originally found) that run up to 500 kbps. They will only be transmitting 50 to 100 MQTT data points with only a few changing rapidly.
Maybe you need the business version of StarLink. $500/month after buying the hardware. 300-500Mbps.
We’ve looked into it towards the end of 2021 and ran into problems. I wasn’t the one who spoke to them but we were told there wasn’t any coverage in the areas where we operate in.
Also, someone on our team ordered it for their home in January this year. That delivery date has been delayed and delayed multiple times. Now he won’t get it until at least July this year.
We can’t wait that long.
I've also been on the waiting list for several months for the normal service. The StarLink site implies their's no wait for the business-class service.
Perhaps we need upcoming technologies like starlink to cover the entire globe including rural areas and maritime industries and flights with Internet services!
It depends where you are. Polar coverage isn’t operational yet. You can order, but it won’t ship till coverage is available. I’m not sure if this applies to @jacob.ramirez’s application. There may be other issues in some areas.
When we spoke to someone at the end of 2021, there wasnt any coverage in our main areas but now the map on the site shows more coverage than that time.
Still some areas not covered at the moment but may be added towards the end of the year.
I will try and find out more information on if that is an option for us.