1.   Those domain root servers essentially keep identical copies of the information for the .com, .net and other domains that are approved by ICANN.

2.   Microsoft Corp. has hired network company Akamai Technologies Inc. to operate backup domain name servers, the network equipment that directs Internet traffic.

3.   On the Internet, addresses are standardized by computers known as domain name servers, which keep identical address books.

4.   Problems with domain name servers are not uncommon, said Ryan Russell, incident analyst for SecurityFocus.com, based in San Mateo, Calif.

5.   There are tens of thousands of domain name servers around the world.

6.   They say tens of thousands of such machines, known as domain name servers, need to be updated.