Xbox Live Connection Lags?

[Queef]

For the past 3-4 years my xbox live connection worked great, little to no lag and disconnections. All of a sudden i'm getting unplayable lag in online games and frequent connection interrupted. I run a wired connection from my xbox to my laptop which then runs wireless to my router, now some of you are probably thinking this has got to be the problem and i do to but as i said ive never had this issue before and id like to test whether it works if i connect my xbox straight to the router but i have no xbox live time to test online games and i'm not buying any incase it doesn't work.

Any Ideas?

I use a DLINK DIR600.