Network Solutions on Monday apparently began suffering a distributed denial of service (DDoS) attack that left its customers unable to access DNS servers, hosted websites, servers, or email accounts.

Reports of outages began appearing late on Monday, and by Tuesday the company was blaming a DDoS attack. "Some customers may see interruptions caused by a ddos distributed denial of service attack. Our network folks are working on it," said multiple posts to the Network Solutions Twitter feed on Tuesday morning.

In a direct response to a customer query on Tuesday, another Network Solutions Twitter message said, "We are dealing with external factors. Your sites are up but dados preventing ppl from reaching. Them"--suggesting a chaotic environment in the support center, as well as the continuing persistence of the DDoS (apparently mistyped as "Dados") attack.

A Network Solution spokesperson didn't immediately respond to a request for comment.

"Network Solutions indicated to us that they had a major DoS attack, which crippled their system, and anyone who has a domain name registered with them," said InformationWeek reader Robert N. Goldstein, president and CEO and Hospitality Consultants, via email. "The result was that no access to servers or domains was possible for several hours," beginning at approximately 6:30am on Tuesday, Eastern time.

"Anyone looking for our domains or our exchange mail this morning, could not reach us--'Oops!!!' is all they got," he said. Based on his company's server logs, however, the attack appeared to ease a couple of hours later, as its websites and hosted email again became accessible.

Calls to multiple Network Solutions helpline phone numbers on Tuesday led to a brief message saying that "all trunks are busy, please try your call again," before disconnecting.

Earlier in the day, however, the message was different. "The main greeting at Network Solutions alerted callers that they had a major DDoS attack, though the person who finally answered my call said that they were undergoing a 'system upgrade.' When I challenged him as to the real reason for the system shutdown, he affirmed that it was in fact a service attack," said Goldstein.

A DDoS attack typically floods a target server with packets, leaving it unable to respond to any requests. Attackers often use botnets for this purpose, although groups such as Anonymous have released software, such as Low Orbit Ion Cannon, that people can run from their own PC. (Note, this may lead to arrest.)

Would switching to a different company help Network Solutions customers sidestep DDoS attacks? The answer is, not likely. That's because stopping a DDoS attack can be quite difficult for any organization, even a domain registrar the size of Network Solutions. In 2010, for example, Arbor Networks saw high-end DDoS attacks topping out at 50+ Gbps range, which is enough packet volume to stop even large data centers and carrier backbones.

For comparison's sake, when LulzSec targeted the CIA's externally hosted public website last week, the agency's response was simply to pull the plug on the website and wait out the attack.

Furthermore, attackers are getting savvier about finding network weak points, such as misconfigured domain name servers (DNS), which enables them to create a DDoS using relatively fewer resources.

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