ASP

AJAX

Java

Browser support

Supported by all recent browsers.

Supported by all recent browsers.

Supported by all recent (desktop) browsers.

Mobile support

Supported by most new web-enabled cell phones and mobile devices.

Supported by most new web-enabled cell phones and mobile devices.

Java is not supported by the browsers on most cell phone and mobile devices.

Plug-in / Active X

No plug-in or Active X object required. Web page downloads immediately.

No plug-in or Active X object required. Web page downloads and starts updating immediately.

Web browser must download and install standard Java plug-in before it can display applets.

Update speeds

Manual updates - User must refresh the web page to see new information.

Automatic updates - fast update speeds.

Automatic updates - very fast update speeds.

System resources

Uses very little client or server side resources.

Can use a lot of client side system resources when updating a large number of points at fast update rates. Also may use a lot of server side resources when connecting to a large number of simultaneous users.

Uses very little system resources on either client or server, compared with AJAX implementation.

Security

Web connection can be password protected.

Web connection can be password protected.

Web connection can be password protected.

Firewalls

Works through firewalls using the standard web port.

Works through firewalls using the standard web port.

Requires firewall to be configured to open dedicated port number.

Licensing

DataHub Web Server license covers unlimited number of ASP client connections.

DataHub Web Server license covers unlimited number of AJAX client connections.

Requires DataHub TCP Link license for each web connection. You can pool connection licenses to optimize licensing costs.

Programming

Powerful DataHub scripting language allows calculations to be performed on the server and sophisticated web reports to be displayed in the browser.

Uses standard JavaScript to develop complete client side web applications.

Very easy HTML code to embed Java applets in a standard web page (we provide example code and applets). Requires knowledge of Java to build your own custom applets.

Other features

These different visualization methods can also be used together in the same page. For example, we often use ASP code to dynamically create AJAX tables that display live data in a web browser. The APS code does the repetitive task of writing table entries for each point in a specific DataHub domain and the web browser interprets the resulting JavaScript and builds the AJAX display accordingly. You can also use ASP to access data from an ODBC database and display it as part of the web page along with the live data from the DataHub.