Real-Time Data Acquisition Applications in ASP.NET

[jude]

Hello,
We are starting to discuss a new ASP.NET application that will be a data
acquisition display application. The data to be displayed will come from
multiple sources--database tables, serial and Ethernet PLCs, OPC servers,
etc. The application will need to display graphic gauges and charts, in
addition to the actual values retrieved from the various data sources. The
application will need to continually update itself in a real-time manner so
that the latest data is always displayed on screen.

First, can an ASP.NET application be made to do such a thing? (Management
wants this new app to be browser/intranet based.)
Second, if a real-time data acquisition app can be developed in ASP.NET, how
or where would one start?
Does anyone know of any good resources (books, Internet sites, etc.) on
creating such a beast?

Thanks.

 

[Lucas Tam]

The
application will need to continually update itself in a real-time
manner so that the latest data is always displayed on screen.

First, can an ASP.NET application be made to do such a thing?

Yes, using Javascript Remoting (or Client Side Callbacks - same thing).

(Management wants this new app to be browser/intranet based.)
Second, if a real-time data acquisition app can be developed in
ASP.NET, how or where would one start?

Take a look here:
Build Your Own: http://www.ashleyit.com/rs/main.htm
BYO for ASP.NET (based on the above technology):
http://www.thycotic.com/dotnet_remotescripting.html
Prepackaged: Dart Live Controls (expensive)

http://maps.google.com is a good example of client side callbacks using
Google's AJAX technology. If you can wait for ASP.NET 2.0, Microsoft will
have these features built into .NET 2.0.

 

[Brock Allen]

Browser based apps don't lend themselves to this sort of thing since HTTP
is a disconnected protocol. There are tricks you can do to simulate this
sort of application, but you're going against the grain. You typically need
a connected style of application (or at least underlying plumbing). You might
want to consider a Click-Once style application instead, which is really
a desktop app that can make dedicated connections to your server/source of
data. The Click-Once aspect is to make it easier to deploy which has historically
been the reason people prefer to build browser based applications.

 

[Guest]

Jude why would you want to build an application and for what kind of
business? Possibly Geophysics or some kind of field communications,
Telecommunications?

 

[jude]

Hi Brock,
Thanks for the info. However, I don't think I'm familiar with a Click-Once
style application. Can you elaborate a little?
Thanks.

 

[jude]

Well, I am Sam, we currently have a Windows-based application for displaying
data measured from industrial processes (things such as temperature,
pressure, etc.). But it requires the client software to be installed on
every computer at the plant site (at least the ones that need to view the
data). Note, we have server software too that has the responsibility of
collecting the data, performing calculations, storing the data in a
database, and so forth.

So, our management team decided that they'd like to reduce some costs by
having a browser-based application to do the same thing (i.e., keep the
server performing the same functions, but having a new client to display the
data), thereby elminating the need for client software installations (all
they would need is a browser).

 

[Brock Allen]

Hi Brock,

Thanks for the info. However, I don't think I'm familiar with a
Click-Once
style application. Can you elaborate a little?
Thanks.

Click-Once is Microsoft's new auto download and install feature in .NET 2.0.
It's meant to address the classic install issue of the IT guy walking around
to everyone's machine to install your app. Then what about an update? Eeek!
There he goes again... to everyone's machine... You get the idea.

Here's a MSDN article on it. It should give you a bit more info:

http://msdn.microsoft.com/msdnmag/issues/04/05/clickonce/default.aspx

 

[Brock Allen]

So, our management team decided that they'd like to reduce some costs

by having a browser-based application to do the same thing (i.e., keep
the server performing the same functions, but having a new client to
display the data), thereby elminating the need for client software
installations (all they would need is a browser).

FWIW, this is exactly what Click-Once is supposed to remedy (as long as you've
done the one-time install of the .NET 2.0 Framework)