Hitchhikers Guide to the Internet | Page 3

reference is made to the source and this copyright is included in whole copies.
This document assumes that one is familiar with the workings of a non-connected simple IP network (e.g. a few 4.2 BSD systems on an Ethernet not connected to anywhere else). Appendix A contains remedial information to get one to this point. Its purpose is to get that person, familiar with a simple net, versed in the "oral tradition" of the Internet to the point that that net can be connected to the Internet with little danger to either. It is not a tutorial, it consists of pointers to other places, literature, and hints which are not normally documented. Since the Internet is a dynamic environment, changes to this document will be made regularly. The author welcomes comments and suggestions. This is especially true of terms for the glossary (definitions are not necessary).

In the beginning there was the ARPAnet, a wide area experimental network connecting hosts and terminal servers together. Procedures were set up to regulate the allocation of addresses and to create voluntary standards for the network. As local area networks became more pervasive, many hosts became gateways to local networks. A network layer to allow the interoperation of these networks was developed and called IP (Internet Protocol). Over time other groups created long haul IP based networks (NASA, NSF, states...). These nets, too, interoperate because of IP. The collection of all of these interoperating networks is the Internet.
Two groups do much of the research and information work of the Internet (ISI and SRI). ISI (the Informational Sciences Institute) does much of the research, standardization, and allocation work of the Internet. SRI International provides information services for the Internet. In fact, after you are connected to the Internet most of the information in this document can be retrieved from the Network Information Center (NIC) run by SRI.

Operating the Internet
Each network, be it the ARPAnet, NSFnet or a regional network, has its own operations center. The ARPAnet is run by BBN, Inc. under contract from DARPA. Their facility is called the Network Operations Center or NOC. Cornell University temporarily operates NSFnet (called the Network Information Service Center, NISC). It goes on to the
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regionals having similar facilities to monitor and keep watch over the goings on of their portion of the Internet. In addition, they all should have some knowledge of what is happening to the Internet in total. If a problem comes up, it is suggested that a campus network liaison should contact the network operator to which he is directly connected. That is, if you are connected to a regional network (which is gatewayed to the NSFnet, which is connected to the ARPAnet...) and have a problem, you should contact your regional network operations center.
RFCs
The internal workings of the Internet are defined by a set of documents called RFCs (Request for Comments). The general process for creating an RFC is for someone wanting something formalized to write a document describing the issue and mailing it to Jon Postel ([email protected]). He acts as a referee for the proposal. It is then commented upon by all those wishing to take part in the discussion (electronically of course). It may go through multiple revisions. Should it be generally accepted as a good idea, it will be assigned a number and filed with the RFCs.
The RFCs can be divided into five groups: required, suggested, directional, informational and obsolete. Required RFC's (e.g. RFC-791, The Internet Protocol) must be implemented on any host connected to the Internet. Suggested RFCs are generally implemented by network hosts. Lack of them does not preclude access to the Internet, but may impact its usability. RFC-793 (Transmission Control Protocol) is a suggested RFC. Directional RFCs were discussed and agreed to, but their application has never come into wide use. This may be due to the lack of wide need for the specific application (RFC-937 The Post Office Protocol) or that, although technically superior, ran against other pervasive approaches (RFC-891 Hello). It is suggested that should the facility be required by a particular site, animplementation be done in accordance with the RFC. This insures that, should the idea be one whose time has come, the implementation will be in accordance with some standard and will be generally usable. Informational RFCs contain factual information about the Internet and its operation (RFC-990, Assigned Numbers). Finally, as the Internet and technology have grown, some RFCs have become unnecessary. These obsolete RFCs cannot be ignored, however. Frequently when a change is made to some RFC that causes a new one to be issued obsoleting others, the new RFC only contains explanations and motivations for the change. Understanding the model on which the whole facility is based may involve reading the original and subsequent RFCs on the topic.
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(Appendix B contains a list of what