Xbox, PlayStation networks under DOS attack on Christmas Day

Theoretically impossible, with the requirements you need for something like PSN or MSLive.

Indeed. Most people dont know the difference between a "hack" attack, and a "denial of service" or "distrubuted denial of service" attack.

I agree with your premise but must ask....if every legitimate connection from a PS or an XBox comes from a MAC address already known to Sony/Microsoft by virtue of the fact that they assigned/recorded such addresses at time of manufacture could they not set up a firewall/filter that rejected traffic from unknown MAC addresses?

I also confess to being mostly unfamiliar with the DOS-ers methods i.e. are they using hacked consoles or are they using PCs running scripts etc.?

I realize spoofing etc might defeat such countermeasures in part and that the vast majority of consoles are behind routers, gateways, etc.

I know that a variety of sites, some legitimate and others less so, have fought these battles in the past and achieved some semblance of immunity.

My kid is a straight A student, book worm, gym rat and a beast on the lax field. He earns his down time and gaming is his guilty pleasure. I really can’t say anything since he is such a machine. I got him an X Box One and some killing games for a well deserved present. He was looking forward to spending the day in a recliner killing zombies and aliens. Those punks ruined his day. I hope they meet up some day.They will be lucky to make it back to their mom’s basement.

I agree with your premise but must ask....if every legitimate connection from a PS or an XBox comes from a MAC address already known to Sony/Microsoft by virtue of the fact that they assigned/recorded such addresses at time of manufacture could they not set up a firewall/filter that rejected traffic from unknown MAC addresses?

That would do a lot to help; the problems that would crop up are (a) MAC spoofing, (b) middle-man connections [proxies, routers, etc] and (c) the possible legal implications, as this would effectively deny 3rd party adapters.

I also confess to being mostly unfamiliar with the DOS-ers methods i.e. are they using hacked consoles or are they using PCs running scripts etc.?

While I am a programmer, I am not particularly knowledgeable about black hat operations, so I can't say anything with certainty there.

I realize spoofing etc might defeat such countermeasures in part and that the vast majority of consoles are behind routers, gateways, etc.
I know that a variety of sites, some legitimate and others less so, have fought these battles in the past and achieved some semblance of immunity.

I think what they've done in [most of] those cases is essentially widen up their bandwidth, and implement some sort of filtering.