Interactive Web View

[robbudge]

Hi,

We have system currently running on a Semi-Mobile piece of industrial equipment.

The site would like the operator the ability to access the screens via PDA or other compact hand held device.

Is it possible on a local Wireless Network to have full web access similar to DAQ Connect ???

Or would VNC etc be more suitable ???

[AzeoTech]

For a single user, running on a local network, VNC is probably best. The problem with VNC is that only one person can connect in at once and local control is (usually) disabled. The other problem is speed, but on a LAN that should not be an issue. DAQConnect solves all these problems, but does require the Internet.

[BeeHay]

I've noticed that with Intranet or Internet viewing, pages with graphs will cause DF to periodically "hang" and the graph doesn't even display, so I've resulted into making "scaled down" pages with only data shown in Variable Value Components...

I've even made a few custom pages for viewing on your cell phone.

I'm also trying to get my WinCE device running DF on it, so our users can input data outside of our trailer unit, and it remotely saves to our DAQ pc so then DF reads the file and inputs the new data.

Only thing I've noticed that's an issue is only 1 username and 1 password.

Also, you have to assign the pages you want to be viewed in a start-up sequence somewhere -

Page.WebView = "Page_4"

I'm not sure what the page name assignment does, I've always had to use the pages actual DF name...

i.e. - The above assigns page webview to page_4, but when I access it on our network, I have to type in *my ip*/webview...

I guess if you want control of the system, you'd have to remote in...Not sure if there is another way of controlling it, but usually in our situation, satellite remoting usually fails.

HTH

[AzeoTech]

All this, plus the fact that putting your SCADA system on the Internet (meaning where it can be accessed from outside) is very unsecure, is why DAQConnect was created. VNC works as well, but has significant limitations: one connection at a time, no control over what someone sees, access to much of the system, load on the scada system itself, etc.

If you can't use DAQConnect, presumably because you don't have Internet, only LAN access, its better to install Apache or other webserver, preferably on another computer, but not required, and then use the page.capture() function to capture screenshots of pages that the other web server software can serve up. For control capability, you could rig up something that either has that server write to a file, take in email commands using DAQFactory POP capability (very unsecure), or even use the built in ethernet server to handle the connection manually, though again only one connection at a time.

[BeeHay]

Hmm, I don't want to step on your toes here, but I just tested accessing our DAQ from the web with 3 users and my phone, it did take a few seconds to connect, but all 4 connections were successful, although I noticed I did not have to input the UN and PW from my phone...

I also feel pretty secure where its at because first you have to know our satellites direct ip, and then the DF UN and PW that I change on every job...

Most of the time though, the company man drives out to location, accesses our wireless router, then views DF data...No internet involved many times.

I understand that the built in webserver is becoming antiquated, but it seems to do what we need just fine...(except for finding our website files, still having a tough time with that! )

[BeeHay]

Oh, did you mean if you control DF through the webserver it's only one connection?

Is there a way to display how many connections are made and possibly connection info?

Thanks for everything AzeoTech!

[AzeoTech]

I was talking about VNC when I said one user at a time. And while you can have many connections into DAQFactory, you have to remember that each one puts load on the system, a system that should be concentrating on something else, namely the SCADA. DAQConnect offloads all this.

As for security, hackers are lazy. They aren't manually going through and finding IPs. They write little bot programs that scan for them. So they don't have to know the sat IP, the bot will find it quick enough. If you look in logs for any public website you'll see tons of entries for bots probing the website for holes.

The DF user name and password is not particularly secure, especially since the connection is over HTTP. Once that bot found a web server, it could monitor traffic on it and extract the user name and password.

But even more likely, all this probing creates load on the SCADA system because DF has to be busy handling the requests (or denying them). A bot can fire off lots of requests quickly, creating essentially a denial of service attack and temporarily hang DAQFactory.

So, as I said, if you really want a publicly facing website, either use DAQConnect (preferred), or use the page.capture() function to capture screenshots and then transfer them to publicly facing web server on another computer.

[BeeHay]

Ah yes, I almost forgot about the Angry IP scanner!

Maybe I should revert to the FTP page capture uploads that I had running for a while and not worry about it.

Sometimes I think that I overthink the situation.

Thanks for the masterful bonk on the head AzeoTech.