LAS VEGAS -- A skeptical but mostly respectful crowd of Black Hat security attendees Wednesday listened intently as National Security Agency Director Keith Alexander defended controversial U.S. surveillance programs in a keynote address.
The nearly hour-long address was interrupted a couple of times by what appeared to be a single heckler as Alexander argued that NSA spy programs exposed by fugitive document leaker Edward Snowden were legal and vital to national security.
Alexander insisted that the widespread fears that the NSA is snooping on domestics phone calls and collecting data on innocent Americans are misplaced, contending that critics don't understand how the spy programs function.
He also said that the secret Foreign Intelligence Surveillance Court that authorizes specific NSA data collection activities is no rubber stamp, as the critics have widely alleged.
Alexander used the bulk of his keynote to describe the controls in place to ensure that NSA surveillance activities focus solely on counter-terrorism.
"What comes out is that we are collecting everything. That is not true," Alexander insisted.
"The assumption is that people are just out there wheeling and dealing. Nothing could be further from the truth," he added, citing controls in place that prevent NSA searches not specifically tied terrorism related activities or terrorist suspects.
The genesis of the NSA phone metadata records collection program, and the PRISM program under which it collects data directly from major Internet service providers, is the World Trade Center bombings of 1993, Alexander said.
Since then, U.S. intelligence agencies have been under tremendous pressure to collect data that can "connect the dots" of terrorist activity, he said. Over the years, the NSA has combined the PRISM program with the collection of phone metadata records such as the originating and dialed number, call time and duration and location data to identify potential terrorist plots in the U.S. and elsewhere.
Alexander contended that such data collection activities have helped the NSA identify and stop 54 terrorist plots including 13 in the United States, 25 in Europe and 11 in Asia in recent years.
The NSA does not as a matter of routine, listen in on phone calls, monitor email content or collect personal data, Alexander maintained. Only 22 NSA officials can authorize such searches and only 35 NSA analysts have the ability to run queries on the data collected. Every query needs to be specifically related to an anti-terror investigation and is fully auditable, he said.
Alexander also noted that U.S. spy programs are overseen by all three branches of government along with the Foreign Intelligence Surveillance Court, he said. The detailed queries that the NSA has run against the information it has collected involves only 500 or so phone numbers, Alexander said.
"The intent of the programs are to find terrorist actors and report that to the FBI," he said.
One audience member briefly heckled Alexander and characterized his descriptions of the spy programs as "bullshit." For the most part, though, the capacity crowd appeared to appreciate Alexander's efforts to explain the program.
At one point the crowd broke into broad applause when he asked the heckler to read up the Constitution after being urged to do the same by the heckler.
He also described as "bullshit" suggestions that the NSA might be exceeding legal limits in its use of phone metadata and data collected under the PRISM program. Congressional investigations have found that the program is operating legally, he said.
Concerns about audience reaction to an NSA presence had earlier prompted organizers of the DEFCON hacker conference to disinvite government employees.
Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at @jaivijayan, or subscribe to Jaikumar's RSS feed . His email address is email@example.com.