The investigation could take weeks, but an initial finding linked a Chinese Internet Protocol address to one of the banks affected.

NPR: SKorea Ready For More Cyberattacks; Banks Recover

In this case, Spamhaus's Domain Name System (DNS) servers were targeted - the infrastructure that joins domain names, such as bbc.co.uk, the website's numerical internet protocol address.

BBC: Global internet slows after 'biggest attack in history'

Type in "Paypal.com, " for instance, and the DNS server owned by your broadband provider converts that name into the Internet Protocol address where the site is hosted.

FORBES: Magazine Article

Fast flux takes advantage of an option built into the Web's architecture, which allows site owners to switch the Internet Protocol address of a site without changing its domain name.

FORBES: Future Phishing

If the user enters the wrong password several times and then is connected to the Internet, the company will locate the computer through its Internet protocol address, information that can help law enforcement agencies recover the computer, Lide said.

CNN: Mobile PCs can be risky on the road

In the suit, Ms. Kelley and her husband, Dr. Scott Kelley, allege that they never gave the FBI permission to look through their email accounts, except to check the Internet Protocol address of one email that mentioned Ms. Kelley and prominent Defense officials.

WSJ: Woman in Petraeus Matter Files Lawsuit

We are contacting you because our records indicate that the Internet protocol (IP) address provided to us by the copyright owner was assigned to your service on the date and time identified by the copyright owner.

FORBES: Verizon Has Already Started Warning Pirates

But these opportunities also poses a challenge: As more and more devices get connected to the Internet including computers, smartphones, innovative cloud computing platforms, and smart-grid tools each of them is going to require an Internet Protocol (IP) address.

WHITEHOUSE: Office of Science and Technology Policy Blog