For anyone that wants the option to connect their Nexus 7 by Ethernet instead of wi-fi, for example when traveling, sometimes hotels provide free wired internet but charge daily for wireless....
Or those of you that have a wired connection at work but no wifi connection ....
My USB-to RJ45 Ethernet Adapter works with the Nexus 7, With the addition of an OTG cable - Micro-USB to Full sized female USB.
You do not have to be Rooted on the Nexus 7.
Just turn off Wi-Fi in Android settings, attach the adapter, start the browser, and you are connected.
The Nexus 7 (Jellybean) does not give you any indication of having established the Ethernet connection in the notification bar. The only way you know it is working is to use your browser.
The router at the other end of the ethernet wire must be assigning IP addresses. For other Tablets, such as Toshiba Excite and ASUS Transformers, Android also displays a menu for Ethernet, to set you own IP. This is not the case with Nexus 7 tablet and Jellybean, however.
My adapter is available on Link: BobjGear's Store on Amazon