said by KillRoy:There is an Xbox thread here. I'm reading that when some people experiencing the outage get assigned an IP address, that it is coming with an MTU of 576 which is incompatible with Xbox.
However there is still a big issue with online gaming especially XBox Live where we're still down. On the Xbox.com site they give a report/update every 30+min and still no fix.
To check and see if you got the right MTU, on the 3600 and probably the 3800, check in the modem under settings, Broadband, status. Right underneath the Mac address is the MTU setting that is being reported being set at 576. Since I'm not part of this outage, mine is showing 1500.