aw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. X.25, Internets, Intranets, and Extranets X.25, Internets, Intranets, and Extranets networks made to look like a single network. Reality states more specifi- cally that the Internet is a collection of thousands of networks with no cen- tral management or policymaking body. It is linked together by a common set of protocols (TCP/IP) that make it possible for users on any one of the networks to communicate with or use the services located on any of the other networks. The Internet Engineering Task Force (IETF) develops tech- nical specifications for the Internet. The specifications are called Requests for Comment (RFC). If someone sees a better way of conducting business or access methods on the Internet, the process enables the RFC to be submit- ted to the IETF for evaluation and implementation. The current Internet is evolving as a commercial and electronic com- merce network for just about every business and residential environment. The commercialization has set the pace for the explosion of connectivity and use. Newer applications have also changed the custodianship and manage- ment of the network. The newer players, as shown in Figure 7-13, include Local Internet Service Providers (ISPs) (local providers, mom-and-pop shops, and SO on) Regional ISPs (local telephone companies, PREPnet, MIDnet, and others) National ISPs (AT&T WorldNet, Sprint, UUNet, Earthlink, and SO on) Dial-up Figure 7-13 The new Internet. Regional Regional National ISPs (ATT, Sprint, Local Regional MCI/WorldCom) Local Local Dial-up Dial-up Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. X.25, Internets, Intranets, and Extranets Chapter 7 With this commercialization, a wide variety of options became available to gain access to the network. These newer providers have ta