RFC 821

I found the book quite enlightening. I have always suspected that the RFCs are succinct works of technical documentation, one thing they are not is scary. A good book welcomes you into a world of authoritive technical information out there on the Internet rarely touched by the programmers and power users who could really use them.

One just need a tour guide. After reading some Linux HOWTOs and a select few O'Reilly and Associates technical books, I discover all I need to learn are either in these books, or these books play the role of tour guides and point you to the real thing. The real thing being IETF standards (RFCs) and the documentations that comes with the Free Software that implement and use these standards. Programming Internet Email is a perfect example.

The book will help you fit together a dozen RFCs that describes how standards-based, secure and scalable electronic email communication can happen. The book will translate the science into practical everyday scripts and Perl modules (and Java classes) howtos. It's a must have.

I hope this book review is of value.

Next : RFC 821 : 1

   RFC 821

                     SIMPLE MAIL TRANSFER PROTOCOL

                           Jonathan B. Postel

                              August 1982

                     Information Sciences Institute
                   University of Southern California
                           4676 Admiralty Way
                   Marina del Rey, California  90291

                             (213) 822-1511



RFC 821                                                      August 1982
                                           Simple Mail Transfer Protocol




                           TABLE OF CONTENTS

   1.  INTRODUCTION .................................................. 1

   2.  THE SMTP MODEL ................................................ 2

   3.  THE SMTP PROCEDURE ............................................ 4

      3.1.  Mail ..................................................... 4
      3.2.  Forwarding ............................................... 7
      3.3.  Verifying and Expanding .................................. 8
      3.4.  Sending and Mailing ..................................... 11
      3.5.  Opening and Closing ..................................... 13
      3.6.  Relaying ................................................ 14
      3.7.  Domains ................................................. 17
      3.8.  Changing Roles .......................................... 18

   4.  THE SMTP SPECIFICATIONS ...................................... 19

      4.1.  SMTP Commands ........................................... 19
      4.1.1.  Command Semantics ..................................... 19
      4.1.2.  Command Syntax ........................................ 27
      4.2.  SMTP Replies ............................................ 34
      4.2.1.  Reply Codes by Function Group ......................... 35
      4.2.2.  Reply Codes in Numeric Order .......................... 36
      4.3.  Sequencing of Commands and Replies ...................... 37
      4.4.  State Diagrams .......................................... 39
      4.5.  Details ................................................. 41
      4.5.1.  Minimum Implementation ................................ 41
      4.5.2.  Transparency .......................................... 41
      4.5.3.  Sizes ................................................. 42

   APPENDIX A:  TCP ................................................. 44
   APPENDIX B:  NCP ................................................. 45
   APPENDIX C:  NITS ................................................ 46
   APPENDIX D:  X.25 ................................................ 47
   APPENDIX E:  Theory of Reply Codes ............................... 48
   APPENDIX F:  Scenarios ........................................... 51

   GLOSSARY ......................................................... 64

   REFERENCES ....................................................... 67