Het Dwalt, thanks for the link, followed the instructions ... but it didn't work for me. So Ive used the pinouts listed in the post (plus the ss line from pin d10 identified from the arduino-ethernet-shield-06-schematic.pdf ) with my nano. Then I linked up the ICSP and power lines up and ... hey presto i've got a functioning (if not a little spaghetti like) ethernet gateway. Thanks very much Simon

@spork said: How would I be able to tell if I was underpowering the Ethernet module? I have built the ethernet GW recently (genuine Arduino Uno and W5100) and it works like a charm. Try to power it up from an iPhone/iPad charger - they are powerful enough. By the way, Arduino Uno + W5100 + nrf24l01+ take about 250mA

Hello. Thanks for all the fast responses. I will look at my gateway code and see if I have missed something. Best regards Andreas