The SCO Group, an industry pariah since it sued IBM alleging that it misappropriated SCO's Unix trade secrets and put them in Linux, says it experienced a massive denial of service (DoS) attack last Friday that consumed 90% of its ISP's available bandwidth, about 150 Mbps, the equivalent of about 100 T1 circuits.

SCO's ISP termed the attack "large" and "extremely well-orchestrated." It thinks the perpetrator or perpetrators put a BOT or worm on a compromised machine that loaded the worm on "hundreds of other machines" and they all hit at once.

The ISP has reportedly identified 138 different machines as the intermediate source, but could not identify the original source. The ISP, which declined to say what operating system or systems were on the infected machines, characterized the attack as the second largest it has ever encountered.

The FBI's Cyber Crimes Division in Salt Lake City was brought in and SCO says the US Attorney's Office is also investigating.

Late last week SCO publicly started putting a little meat on the bones of its charges and claimed that Linux is "riddled" with its Unix IP. It alleged that a comparison of Unix and Linux source code has turned up a "significant" number of lines of SVR5 in Linux - in the kernel, in associated files and in add-on files. There are also supposed to be "substantial" instances of barely redacted lines of Unix code in Linux. SCO said it's still not sure yet how big the piracy is.

SCO said in a statement that it is "examining whether a link exists between SCO's legal action and some of the Linux community who are hostile toward SCO for asserting its legal rights."

SCO is promising to prosecute. "Unfortunately," it said, "some programmers who disagree with SCO's corporate policies have ignored the seriousness of cyber terrorism. This was a mistake on the part of the people involved, because we will prosecute them to the fullest extent of the law and will do everything possible to assure that justice is done for the commission of this crime."

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