Can anyone give an idea of how large, compared to other DDOS attacks, 50 GBPS is?
However, most routers and firewalls also have a limit on packets per second they can process, on top of the throughput limits. I've got a 100Mbps commit on a 1000mbps pipe, and I can handle 1000Mbps of 'normal' traffic... but I got taken out a month back by a 200Mbps DDos that used very small packets. My router couldn't handle it. (now, if I had spent money on a better router, it wouldn't be a problem. As far as I can tell, even, a reasonable software router could have handled it.)
Another way to measure this is the capacity required to absorb the attack. You can get he.net bandwidth for around a thousand dollars a month per gigabit, and he.net is about as cheap as bandwidth gets, so to soak a 50 gigabit attack, you'd have to have fifty thousand dollars a month of spare capacity.
(I'm sure there are further discounts available between the 1GiB and the 50GiB tier... but you get the idea. )
More to the topic: It's much more likely that the motivations are financial.
It's about China bullying people around and trying to censor the internet.
As an example of how outdated a typical Windows XP install is in China, I'm running a site which has 95% traffic from China. Over 62% of users are on IE6.
50gbps would rank as one of the largest attacks I've ever heard of on the Internet. And I hear about quite a few of the really big ones. :-)
Sites that are routinely targeted for blackmail because they make lots of money have dealing with attacks like this down to a science. Of course they're not going to go out of their way to advertise that it happens all the time to protect their business interests, so that's why you may not have heard about it.
Banks and other financial institutions, gambling sites, large porn sites, top 100 websites and sites that are either vulnerable to brand damage or that have a lot of turnover see an awful lot of this.
50Gbps is at most 50K zombies or so, that's really not that bad.
The largest attacks against sites that I know of used a million ips and more. That's a wholly different kettle of fish and starts to be a real problem because even hardware based packet filtering (Thanks force10!) has its limits.
After a call with one of my hosting providers (yes, on a Sunday at that, how is that for service), they saw the 40Gbit barrier broken somewhere at the end of 2007, today they're prepared for a multiple of that but he says that because they are that well prepared they've become less of a target.
They've invested a very large sum of money in infrastructural components specifically to deal with DDOS attacks at the hardware level, and though he doesn't rule out the possibility that they'll be one day facing one they can't deal with he doesn't seem overly worried, he does not want to claim any upper limit.
The countries they've seen the most trouble from are hard to pin down, but apparently the former USSR states and China are pretty high on hist list for the 'bot masters'.
Extortion seems to have arrived on the internet to stay, if you're a small player and you become successful you'd better be prepared, sooner or later you'll be a target.
Even smaller websites can easily get 2 to 10 Gbps ddos attacks aimed at them, the first time this happened to me I was pretty happy that all that happened was that I received an email from my ISP informing me of the fact without any loss of service.
If you really want to know please drop me a line (email in my profile).
Not a single provider in the world can handle this kind of attack peacefully without service interruption except China Telecom and China Union.
Your calculations can't be more off about 50K bots, our counts showed more than 100K we couldn't count after that due to limitation in software.
My business has been dealing with DDOS attacks since 2002 we pretty much saw the brunt of every kind of new attack that came online. The only thing that can be compared with magnitude to this is the DNS Amplification attack, but that was limited in it's impact considering the source of the attack was diverse not from one geo area.
Yes, there will be an interruption, but you will be able to get the situation back under control while the attack is still in progress. You will need your upstreams/peers to collaborate.
If you're on the Cisco platform, then good luck to you.
I can't cite how I know, but if you look up who I am you can probably guess that I'm aware of the largest DDoS's in the world that take place.