US websites buckle under sustained DDoS attacks
South Korea, too
Websites belonging to the federal government, regulatory agencies and private companies have been struggling against sustained online attacks that began on the Independence Day holiday, according to multiple published reports.
At time of writing, most of the targets appeared to be afloat. Nonetheless, several targets have buckled under the DDoS, or distributed denial of service, attacks, which try to bring down a website by bombarding it with more traffic than it can handle. FTC.gov  was experiencing "technical issues" on Monday and Tuesday that prevented many people from reaching the site, spokesman Peter Kaplan said.
Other sites, including FAA.gov , Treas.gov  and DOT.gov  also experienced outages, a person said familiar with the attacks told The Register. DOT spokeswoman Sasha Johnson said late Tuesday: "The DOT has been experiencing network incidents since this past weekend. We are working with the US Computer Emergency Readiness Team at this time."
Both Kaplan and Johnson declined to say whether their agencies' sites were under attack.
The DDoS attacks appear to be originating from compromised computers located primarily in the Asia Pacific region and are being delivered as plain-vanilla floods of ping, syn and UDP packets, said the person, who asked not to be identified because he wasn't authorized to share the details.
The attacks came as South Korean websites operated by the government and private companies also were hit, the Associated Press reported here . In all, 26 websites, including those run by Nasdaq, the New York Stock Exchange and the Washington Post are being targeted, according to  The Washington Post, which also covered the attacks.
There seems to be some confusion about just how powerful the attacks are. The person familiar with the attacks said they were relatively modest.
"Most are easy to mitigate," the person familiar with them said. "I'm surprised any of these attacks are as effective as they are."
But an unidentified person briefed by government investigators told IDG News  the attacks directed as much as 20 gigabytes to 40 gigabytes of bandwidth per second during their height over the weekend. They have since settled down to about 1.2 gigabytes per second, IDG said. ®