P2P software allows computer users, connected to the Internet, to share files with other users. Files can include music, graphics, images, movies, and text.
Music is what most people associate with P2P networks, but it only accounts for about 15% of traffic; video files account for over 50%. P2P file sharing networks are frequently used to trade digital files of child pornography.
A centralized P2P network relies on a central server to process requests from the peers. A peer sends a request to the central server and the server identifies a candidate that the peer can download from and tells the peer where to get the file. The peer then establishes a direct connection with the download candidate and receives the file.
A decentralized P2P network does not rely on a central server to process requests from peers. Peers send requests to other peers, known as ultrapeers. There are multiple ultrapeers on a network, and peers can connect to multiple ultrapeers. Likewise, ultrapeers can connect to other ultrapeers. The ultrapeer provides the peer with the information to make a connection and exchange files.
All P2P networks share basic features. They allow the user to search, to review the search, and to download a file via direct connection. Some of the more common P2P network names are Gnutella, Gnutella2, Ares Galaxy, and eDonkey. Investigators should also be aware of BitTorrent, which is actually a protocol and not a P2P network. It is one of the most common protocols for transferring large files.
Albuquerque Man Sentenced to Federal Prison for Child Pornography Conviction.
Child Pornography Case Results in Lengthy Prison Sentences: Couple Abused Child in Their Care.
London Man Extradited to Indianapolis on Child Pornography Charges.
News headlines like these three examples are relentless, but they point to one important fact: Law enforcement continues to make headway in identifying, locating, and prosecuting individuals who possess and trade child pornography.
And thanks to recent enhancements to one of the key tools used by many in law enforcement to work these cases, investigators are also making important advancements in identifying child pornography victims.
The tool is called the Child Protection System (CPS)—software that’s provided free to law enforcement to proactively identify and locate child predators. It is used by agencies in 48 countries around the world and in all 50 states.
CPS was developed by TLO, a company launched by data-fusion pioneer Hank Asher. Following his untimely death in 2013, TransUnion bought out TLO and donated CPS to the Child Rescue Coalition, which now operates it and provides training. Asher’s daughters are co-CEOs of CRC. They regard it as their father’s legacy and are continuing his philanthropic efforts to protect children from exploitation.
According to the CRC website:
Investigators use CPS to identify the most dangerous online predators within a massive population of 44 million global unique IP addresses; predators with the longest track record, who have viewed and distributed the greatest number of abuse images and films, and who have exhibited behavior indicating with high likelihood they are a hands-on offender of children in real life.
I recently attended a CPS training event in Florida that was tailored to investigators who are already familiar with the software. As a service to interested law enforcement professionals, I prepared a detailed overview of the meeting—it provides an update on recent changes made within CPS. This training update is available on the SEARCH website, but distribution is limited to law enforcement.
SEARCH offers a 3-day course on P2P Investigations. Instruction covers the CPS suite of programs, giving investigators a firm understanding of the CPS interface and the functions associated with the system’s features. Investigators learn how to query the database, provide deconfliction, and create investigative jobs.
About the Author
Mr. Don Lewis is a High-Tech Crime Training Specialist for SEARCH. He coordinates and provides training and technical assistance on high-tech crime investigations and forensics to local, state and federal justice and public safety agencies. He provides technical assistance to law enforcement agencies in active cases, prepares training curricula, teaches SEARCH investigative courses and speaks at conferences throughout the United States.