Originally Posted by Tennisbum
In other words, can I use my US ethernet cable with a modem in Europe? Or, like phone cables and power plugs, is some sort of adapter required?
In addition to the other responses, note that there are different categories of modern ethernet cable. (e.g., cat 5, cat 5e, cat6 and some earlier Cat3, etc. Cat=category.) The connectors are the same and for most usage you would never know the difference. However, there would be some differences for high-end applications.