VPN Question - Not Restricted to PLCs

[Mike Nash]

When online with a Do-more at our office from home via VPN, the Trend View, PID View and Data View all show a hesitation of approximately 1.53 seconds occurring around 5.5 second intervals. The duration tends to be pretty consistent, the recurrence is less so but regular and always.

I also see this with another device on the same network which is not a PLC but does have a trending display in its software package.

The devices are not hesitating, it is just the update in the views of the data. This happens with different computers also.

I am not a network person by any means which also means I don't really know how to phrase a query to get useful results from a search engine.

Does anyone have any ideas where I need to start looking to at least minimize this? The trend view screen capture below is very typical of what I see.

[plcnut]

All of those data points are being sent over the network to your local PC. There is going to be more and more delay each time you add additional switches and routers between you and the remote device. A VPN is probably going to be relatively low on the QOS (Quality of Service) list. Voip will be at the higher end of the list because of the sound quality issues. I do not know that there is much you can do about it.

[Mike Nash]

I definitely don't know what causes it, but losing 1/4 of the data in big chunks seems a little much. I haven't found anything so far that makes it any worse (browser running, etc.) but no tips to make it better either. I also suspect it is on our office end but?

Thanks though!

[ADC Product Engineer]

This happens a lot with cellular signals.   Cell towers use a consolidating technique to clump the data into burst packets to keep the packet overhead down.  Some ISP's use this same technique to "increase apparent speed".  This plays all sorts of havok with devices that are expecting consistent data flow; IE PLCs.

[Mike Nash]

This happens a lot with cellular signals.   Cell towers use a consolidating technique to clump the data into burst packets to keep the packet overhead down.  Some ISP's use this same technique to "increase apparent speed".  This plays all sorts of havok with devices that are expecting consistent data flow; IE PLCs.

Now that you mention it, I do seem to recall strange pauses in downloads while at the office. I'll check with a co-worker who might be able to check this. Thanks. We are in one of those buildings in an office park that never saw the need to upgrade/install cable for internet access. The charge to have it done for just our office has kept us at DSL so far. We techs tend to download large software updates at home due to this.