protocols - protocols definition file


   This  file is a plain ASCII file, describing the various DARPA internet
   protocols that are available from the TCP/IP subsystem.  It  should  be
   consulted  instead  of using the numbers in the ARPA include files, or,
   even worse, just guessing  them.   These  numbers  will  occur  in  the
   protocol field of any IP header.

   Keep  this  file  untouched  since changes would result in incorrect IP
   packages.  Protocol  numbers  and  names  are  specified  by  the  IANA
   (Internet Assigned Numbers Authority).

   Each line is of the following format:

          protocol number aliases ...

   where  the  fields  are  delimited  by spaces or tabs.  Empty lines are
   ignored.  If a line contains a hash mark (#), the  hash  mark  and  the
   part of the line following it are ignored.

   The field descriptions are:

          the native name for the protocol.  For example ip, tcp, or udp.

   number the  official  number for this protocol as it will appear within
          the IP header.

          optional aliases for the protocol.

   This file might be distributed over  a  network  using  a  network-wide
   naming service like Yellow Pages/NIS or BIND/Hesiod.


          The protocols definition file.




   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.

Free Software

Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.

Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.

Free Books

The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.

Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.

Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.