(Cross posted from Microsoft on the Issues. Editor’s note: The following is a guest post authored by Ernie Allen, president and CEO of the National Center for Missing and Exploited Children).

In late 2009, I wrote on this blog about PhotoDNA, an important technological step forward in preventing the spread of child sexual exploitation online.

Microsoft donated PhotoDNA, a technology created by Microsoft Research in cooperation with Dartmouth College professor Hany Farid, to the National Center for Missing & Exploited Children, so that we could use the groundbreaking image-matching technology with online services companies to stop the online distribution of the worst known images of child rape (aka child pornography).

Today, I’m proud to say that Facebook – a company that has revolutionized life online and, among other accomplishments, is one of the leading photo-sharing services in the world – will implement PhotoDNA on its network to further its commitment to keeping children from being victimized.

In my work for the National Center, I have witnessed the unbelievable scope and intensity of this problem. Since 2002, we have reviewed and analyzed almost 49 million photos and videos of child pornography, including well more than 13 million in 2010 alone. The victims in these images have progressively been getting younger as pedophiles prey on pre-verbal children who cannot ask for help. Of the more than 3,500 children depicted in commonly traded images who have been identified by law enforcement, 10 percent are infants and toddlers and 67 percent are prepubescent.

Many of these images recirculate on the Internet time and time again, even many years after the original crime occurred and the abuser has been brought to justice – and every time these crime scene images are viewed, the children in the images are re-victimized. PhotoDNA aims to break this cycle, so the images of abuse need not haunt these children online forever.

Since the time of the donation, Microsoft has been working with Dartmouth and the NCMEC to test and deploy this technology on Bing, SkyDrive and Hotmail – with compelling success – and is working with other companies who have voiced interest in doing the same. With this adoption, Facebook is joining Microsoft in taking a remarkable stand against child exploitation. Now, when the NCMEC identifies an image for inclusion in the PhotoDNA program, the technology will give online service providers like Facebook, Microsoft and other companies who adopt it in the future the power to identify and remove that image from among billions of photos shared on their services.

I wrote in 2009 that PhotoDNA will revolutionize the work we’re doing in the fight against child pornography, a prediction that is borne out by Facebook’s adoption. But to truly realize that revolution, this technology is needed on many online services – only then will the Internet become a hostile environment for those who would exploit and abuse children.
What can you do to help?

Contact other online service providers – companies that enable social media and photo sharing especially – and encourage them to contact the National Center about adopting PhotoDNA, available for free to any online service provider.

Also, contact your legislators and let them know this is a priority for you. Tell them to encourage voluntary action by online services to more proactively disrupt the spread of child victimization online.
Finally, and most critically, you can help fight the problem of child sexual abuse and exploitation by reporting it. If you see it, if you know about it, if you suspect it, report it to us at www.cybertipline.com or call 1 (800) THE LOST. And, as a user of Facebook, Bing, SkyDrive, Hotmail or any other online service, if you see an image that concerns you or other suspicious activity you think might involve child exploitation, report it as abuse on that service as well.

I’d like to thank Microsoft and Facebook for this important work in helping to make the Internet inhospitable to child abusers and I call on other online service providers to follow their lead. No single organization, no matter how big, can cast a net wide enough to stop the sharing of these crimes, but working together, we can collectively make a difference.

Join me, Facebook, Microsoft and Dartmouth tomorrow on Facebook Live at 3 p.m. ET as we discuss these issues in more detail and other important work being done to protect children online. And for more information about PhotoDNA, I’d encourage you to read today’s post on the Official Microsoft Blog from Bill Harmon of Microsoft’s Digital Crimes Unit or visit http://www.microsoftphotodna.com