Control system with webinterface

I'm starting my frist arduino project and I want to use the matlab+simulink environment to create a control system. But for visualisation of graphs and to change settings I was thinking About a webserver.
Is this possible on the arduino? And can the website be controller by the ethernetboard or must that be processed by the arduino mega board?

Thanks in advanced for your help,
Rob

I was thinking About a webserver.
Is this possible on the arduino?

An Arduino with an Ethernet shield, yes.

And can the website be controller by the ethernetboard

Created by the Arduino and sent using the Ethernet shield or Ethernet version of the Arduino, yes.

or must that be processed by the arduino mega board?

No, you don't need a Mega, but the extra memory is nice.

OK, Thanks for your reaponse.

It seems like something like a Raspberry Pi would make a much better webserver. There's a few good data visualization packages out there, and the Pi is much better for data collection.