Ethernet Shield Capabilities

Projects Networking, Protocols, and Devices
1

Before buying an Arduino Ethernet Shield I though I should ask whether it can actually do what I have in mind.

I want to connect my Arduino to the Internet directly - without the mediation of a computer - and to connect to it using telnet or (preferably) SSH. I noticed in the documentation of the Ethernet library that using the EthernetUDP class one can send and receive UDP packets over the internet. But what is a handy way to do so from a computer's terminal? I have some experience with UDP-based communication using java sockets. But would I have to build such an application from scratch? Is it possible to use telnet and create my own communication protocol over that?

2

There is a telnet server sketch but SSH is probably way too much for the Arduino to handle.

Is it possible to use telnet and create my own communication protocol over that?

Yes.

3

Thanks a lot for the reply! Just one more question: I'm planning to get an Arduino Ethernet combined with the USB-to-Serial adapter. I guess, on my Arduino programming environment I should set the board to Arduino Ethernet. What about the programmer? Should it be AVR ISP, USBtinyISP, USBasp or something else? Also I think that - in terms of cost - it is better to buy an Arduino Ethernet instead of an Arduino Uno plus the Ethernet Shield. What do you think? Thanks a lot!

4

Also I think that - in terms of cost - it is better to buy an Arduino Ethernet instead of an Arduino Uno plus the Ethernet Shield. What do you think?

I think that you would be better off with the board and separate shield. As a beginner, keep it simple. Hardware-wise, adding a shield to the simplest to program Arduino is pretty easy.

On the Arduino store, the Arduino Ethernet and USB adapter are 49.90 euros. The Arduino and Ethernet shield are 49.00 euros. Actually, cheaper by almost a whole euro.

5

PaulS:
On the Arduino store, the Arduino Ethernet and USB adapter are 49.90 euros. The Arduino and Ethernet shield are 49.00 euros. Actually, cheaper by almost a whole euro.

Note: All prices listed below are without VAT for a fair comparison:

Arduino Ethernet Shield Rev3 w/o PoE = 29Euro.
Arduino Uno Rev3 = 20Euro.
Total: 49Euro.

Arduino Ethernet w/o PoE module = 39Euro.

Plus the programmer (USB to Serial) = 10Euro.

Total: 49Euro. (But the adapter is actually sort of an investment - the cost for the construction is 39Euro)

It's absolutely the same! My problem is that my local distributor offers the Ethernet shield (w/o PoE module) at the amazing price of 39Euro! That's why I considered the cost prohibitive in the first place. I might consider ordering the shield and an Arduino Uno if I find out that it comes more economic including the shipping cost. Otherwise, do you think it will be too hard to have an Arduino Ethernet running in a few days?

6

But the adapter is actually sort of an investment

Only if you can use it for something else. If the only purpose is to program the one board, then it isn't.

Otherwise, do you think it will be too hard to have an Arduino Ethernet running in a few days?

That depends on what you want it doing, and your skills and attitude. Probably not, though.