Looking for hardware for a new project

Hello all, I'm new in these forum and I'm starting with arduino.

I have a project in mind but I'm not sure about what is the best hardware for it, I have an arduino Mega that I bought a year ago, now I need connectivity by ethernet and I'm not sure if the best choice is to buy the ethernet shield for the arduino Mega or sell it and buy an arduino YUN.

The project that I have in mind its build a domotic control fully administrated by web (I will work with php, mysql and arduino), my idea is to build an "arduino net" where you can add the arduinos that you need for any size of project.

The server will be a PC, so the arduinos will be only the data readers.

Worth buying YUN and sell Mega or with Mega can be enought for me.

Thanks for your time, English is not my native language so if you read any mistake or something is not understandable, please let me know and I will change it.

Do you need wireless connectivity or will you be able to wire every Arduino you want to include into your network? In the first case the Yun may be a good choice in the later choose the Ethernet shield. You will find much more software for the Ethernet shield (it's much longer on the market) but you theoretically get much more flexibility (the Yun includes a complete Linux system) with the Yun.

As you can see your question cannot be answered clearly without knowing more about your project.

Thanks for your post pylon, my project uses a normal PC who runs like a server (mysql and php) to store, manage and show the data acquired by the arduino board (s) (for ex. temperatures, humidity, digital I/O, etc) so I think that linux of YUN is not useful for me at this point of project.

My idea is to do it all wired and later If all goes ok migrate to wireless system.

YUN and the Ethernet shield have the same posibilities relative at net communications?

YUN and the Ethernet shield have the same posibilities relative at net communications?

No, they don't. With the Ethernet shield most of the TCP stack is in the WizNet5100 chip (hardware), you can just control 4 TCP connections and many of the low level IP stuff you cannot do with that shield. In most Arduino applications this is not really relevant but you might have to consider it for special applications. The YUN does not have direct network control from the Arduino side. You have a connection between the embedded Linux and the Arduino and over that connection you can give some commands to the Linux side in Arduino sketches. This is a very different approach than the Ethernet shield where you directly control network hardware. If you want to use your Arduino just as a network client you might want to consider choosing a WiFi shield instead of the Yun, especially if your not familiar with Linux and have no intentions to get it.