RFC 822

RFC # 822

Obsoletes: RFC #733 (NIC #41952)

Table of Contents

Preface

By 1977, the Arpanet employed several informal standards for the text messages (mail) sent among its host computers. It was felt necessary to codify these practices and provide for those features that seemed imminent. The result of that effort was Request for Comments (RFC) #733, "Standard for the Format of ARPA Network Text Message", by Crocker, Vittal, Pogran, and Henderson. The specification attempted to avoid major changes in existing software, while permitting several new features.

This document revises the specifications in RFC #733, in order to serve the needs of the larger and more complex ARPA Internet. Some of RFC #733's features failed to gain adequate acceptance. In order to simplify the standard and the software that follows it, these features have been removed. A different addressing scheme is used, to handle the case of inter-network mail; and the concept of re-transmission has been introduced.

This specification is intended for use in the ARPA Internet. However, an attempt has been made to free it of any dependence on that environment, so that it can be applied to other network text message systems.

The specification of RFC #733 took place over the course of one year, using the ARPANET mail environment, itself, to provide an on-going forum for discussing the capabilities to be included. More than twenty individuals, from across the country, participated in the original discussion. The development of this revised specification has, similarly, utilized network mail-based group discussion. Both specification efforts greatly benefited from the comments and ideas of the participants.

The syntax of the standard, in RFC #733, was originally specified in the Backus-Naur Form (BNF) meta-language. Ken L. Harrenstien, of SRI International, was responsible for re-coding the BNF into an augmented BNF that makes the representation smaller and easier to understand.

• 1. INTRODUCTION
  • 1.1. SCOPE
  • 1.2. COMMUNICATION FRAMEWORK
• 2. NOTATIONAL CONVENTIONS
• 3. LEXICAL ANALYSIS OF MESSAGES
  • 3.1. GENERAL DESCRIPTION
    • 3.1.1. LONG HEADER FIELDS
    • 3.1.2. STRUCTURE OF HEADER FIELDS
    • 3.1.3. UNSTRUCTURED FIELD BODIES
    • 3.1.4. STRUCTURED FIELD BODIES
  • 3.2. HEADER FIELD DEFINITIONS
  • 3.3. LEXICAL TOKENS
  • 3.4. CLARIFICATIONS
    • 3.4.1. QUOTING
    • 3.4.2. WHITE SPACE
    • 3.4.3. COMMENTS
    • 3.4.4. DELIMITING AND QUOTING CHARACTERS
    • 3.4.5. QUOTED-STRINGS
    • 3.4.6. BRACKETING CHARACTERS
    • 3.4.7. CASE INDEPENDENCE
    • 3.4.8. FOLDING LONG HEADER FIELDS
    • 3.4.9. BACKSPACE CHARACTERS
    • 3.4.10. NETWORK-SPECIFIC TRANSFORMATIONS
• 4. MESSAGE SPECIFICATION
  • 4.1. SYNTAX
  • 4.2. FORWARDING
  • 4.3. TRACE FIELDS
    • 4.3.1. RETURN-PATH
    • 4.3.2. RECEIVED
  • 4.4. ORIGINATOR FIELDS
    • 4.4.1. FROM / RESENT-FROM
    • 4.4.2. SENDER / RESENT-SENDER
    • 4.4.3. REPLY-TO / RESENT-REPLY-TO
    • 4.4.4. AUTOMATIC USE OF FROM / SENDER / REPLY-TO
  • 4.5. RECEIVER FIELDS
  • 4.6. REFERENCE FIELDS
  • 4.7. OTHER FIELDS
• 5. DATE AND TIME SPECIFICATION
  • 5.1. SYNTAX
  • 5.2. SEMANTICS
• 6. ADDRESS SPECIFICATION
  • 6.1. SYNTAX
  • 6.2. SEMANTICS
    • 6.2.1. DOMAINS
    • 6.2.2. ABBREVIATED DOMAIN SPECIFICATION
    • 6.2.3. DOMAIN TERMS
    • 6.2.4. DOMAIN-DEPENDENT LOCAL STRING
    • 6.2.5. BALANCING LOCAL-PART AND DOMAIN
    • 6.2.6. MULTIPLE MAILBOXES
    • 6.2.7. EXPLICIT PATH SPECIFICATION
  • 6.3. RESERVED ADDRESS
• 7. BIBLIOGRAPHY
• APPENDIX A. EXAMPLES
  • A.1. ADDRESSES
  • A.2. ORIGINATOR ITEMS
  • A.3. COMPLETE HEADERS
• APPENDIX B. SIMPLE FIELD PARSING
  • B.1. SYNTAX
  • B.2. SEMANTICS
• APPENDIX C. DIFFERENCES FROM RFC #733
• APPENDIX D. ALPHABETICAL LISTING OF SYNTAX RULES

• Original text document
• Complete HTML RFC (TAR, TGZ, or ZIP format)

Dies ist ein Mirror von Connected: An Internet Encyclopedia von Brent Baccala. Die offizielle Projekt-Homepage findet sich im Web unter www.freesoft.org/CIE. Dieser Mirror wurde zuletzt aktualisiert am Samstag, 28 Januar 2006 18:18 +0100.