The Project Gutenberg eBook of Hitchhiker's Guide to the Internet, by Ed Krol
The Hitchhikers Guide to the Internet
25 August 1987
Ed Krol
krol@uxc.cso.uiuc.edu
This document was produced through funding of the National
Science Foundation.
Copyright (C) 1987, by the Board of Trustees of The University<br>of Illinois. Permission to duplicate this document, in whole<br>or part, is granted provided reference is made to the source<br>and this copyright is included in whole copies.
This document assumes that one is familiar with the workings<br>of a non-connected simple IP network (e.g. a few 4.2 BSD<br>systems on an Ethernet not connected to anywhere else).<br>Appendix A contains remedial information to get one to this<br>point. Its purpose is to get that person, familiar with a<br>simple net, versed in the "oral tradition" of the Internet<br>to the point that that net can be connected to the Internet<br>with little danger to either. It is not a tutorial, it<br>consists of pointers to other places, literature, and hints<br>which are not normally documented. Since the Internet is a<br>dynamic environment, changes to this document will be made<br>regularly. The author welcomes comments and suggestions.<br>This is especially true of terms for the glossary (definitions<br>are not necessary).
In the beginning there was the ARPAnet, a wide area<br>experimental network connecting hosts and terminal servers<br>together. Procedures were set up to regulate the allocation<br>of addresses and to create voluntary standards for the network.<br>As local area networks became more pervasive, many hosts became<br>gateways to local networks. A network layer to allow the<br>interoperation of these networks was developed and called IP<br>(Internet Protocol). Over time other groups created long haul<br>IP based networks (NASA, NSF, states…). These nets, too,<br>interoperate because of IP. The collection of all of these<br>interoperating networks is the Internet.
Two groups do much of the research and information work of<br>the Internet (ISI and SRI). ISI (the Informational Sciences<br>Institute) does much of the research, standardization, and<br>allocation work of the Internet. SRI International provides<br>information services for the Internet. In fact, after you<br>are connected to the Internet most of the information in<br>this document can be retrieved from the Network Information<br>Center (NIC) run by SRI.
Operating the Internet
Each network, be it the ARPAnet, NSFnet or a regional network,<br>has its own operations center. The ARPAnet is run by<br>BBN, Inc. under contract from DARPA. Their facility is<br>called the Network Operations Center or NOC. Cornell<br>University temporarily operates NSFnet (called the Network<br>Information Service Center, NISC). It goes on to the
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regionals having similar facilities to monitor and keep<br>watch over the goings on of their portion of the Internet.<br>In addition, they all should have some knowledge of what is<br>happening to the Internet in total. If a problem comes up,<br>it is suggested that a campus network liaison should contact<br>the network operator to which he is directly connected. That<br>is, if you are connected to a regional network (which is<br>gatewayed to the NSFnet, which is connected to the<br>ARPAnet…) and have a problem, you should contact your<br>regional network operations center.
RFCs
The internal workings of the Internet are defined by a set<br>of documents called RFCs (Request for Comments). The general<br>process for creating an RFC is for someone wanting something<br>formalized to write a document describing the issue and mailing<br>it to Jon Postel (postel@isi.edu). He acts as a referee for<br>the proposal. It is then commented upon by all those wishing<br>to take part in the discussion (electronically of course).<br>It may go through multiple revisions. Should it be generally<br>accepted as a good idea, it will be assigned a number and<br>filed with the RFCs.
The RFCs can be divided into five groups: required, suggested,<br>directional, informational and obsolete. Required RFC's (e.g.<br>RFC-791, The Internet Protocol) must be implemented on any host<br>connected to the Internet. Suggested RFCs are generally<br>implemented by network hosts. Lack of them does not preclude<br>access to the Internet, but may impact its usability. RFC-793<br>(Transmission Control Protocol) is a suggested RFC. Directional<br>RFCs were discussed and agreed to, but their application has never<br>come into wide use. This may be due to the lack of wide need for<br>the specific application (RFC-937 The Post Office Protocol) or<br>that, although technically superior, ran against other pervasive<br>approaches (RFC-891 Hello). It is suggested that should the<br>facility be required by a particular site, animplementation<br>be done in accordance with the RFC. This insures that, should<br>the idea be one whose time has come, the implementation will be<br>in accordance with some standard and will be generally usable.<br>Informational RFCs contain factual information about the<br>Internet and its operation (RFC-990, Assigned Numbers).<br>Finally, as the Internet and technology have...