If you've had any networking problems on the 360, done a network test then pressed Y for detailed status, you've seen a dialog like this (this one's not mine; thanks google image search):
What do all these codes mean? I don't think Microsoft tech support will tell us, perhaps for job security reasons. I can guess some of them:
Type (wired / wireless)
Address / subnet mask
DNS1 / DNS2
N= wireless access point
What about W, X, Y, Z, ID, L, Q and C? I think Q might be the error code, and MS does have an error code search page, but the explanation for code 80070435 (with I've had with a wired connection) is hopelessly uninformative.
Does anyone have any more information?