Minimal FAX address format in Internet Mail
RFC 2304
Document | Type |
RFC - Proposed Standard
(March 1998; No errata)
Obsoleted by RFC 3192
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Last updated | 2013-03-02 | ||
Stream | IETF | ||
Formats | plain text pdf html bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 2304 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | (None) | ||
Send notices to | (None) |
Network Working Group C. Allocchio Request for Comments: 2304 GARR-Italy Category: Standards Track March 1998 Minimal FAX address format in Internet Mail Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (1998). All Rights Reserved. IESG NOTE This memo describes a simple method of encoding PSTN addresses of facsimile devices in the local-part of Internet email addresses. As with all Internet mail addresses, the left-hand-side (local- part) of an address generated according to this specification, is not to be interpreted except by the MTA that is named on the right-hand-side (domain). 1. Introduction Since the very first e-mail to fax gateway objects appeared, a number of different methods to specify a fax address as an e-mail address have been used by implementors. Two major objectives for this were - enable an e-mail user to send faxes from his/her e-mail interface; - enable some kind of "fax over e-mail service" transport, to reduce the costs of fax transmissions, and use the existing e-mail infrastructure. Allocchio Standards Track [Page 1] RFC 2304 Minimal FAX address format March 1998 This memo describes the MINIMAL addressing method and standard extensions to encode FAX addresses in e-mail addresses, as required in reference [13]. The opposite problem, i.e. to allow a traditional numeric-only fax device user to access the e-mail transport service, is not discussed here. All implementations supporting this FAX over e-mail address format MUST support as a minimum the specification described in this document. The generic complex case of converting the whole PSTN addressing in e-mail is out of scope in this minimal specification: there is some work in progress in the field, where also a number of standard optional extensions are being defined. In this document the formal definitions are described using ABNF syntax, as defined into [7]. We will also use some of the "CORE DEFINITIONS" defined in "APPENDIX A - CORE" of that document. The exact meaning of the capitalised words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", "OPTIONAL" is defined in reference [6]. 2. Minimal Fax address The "service-selector" defined in section 2 of reference [13] for the fax service is: service-selector = "FAX" The minimal addressing for the fax service also requires support for a "qualif-type1" element (see section 2 of reference [13]). This element is an OPTIONAL element of the fax address, but its support, when present, is REQUIRED: qualif-type1 = "/" t33-sep "=" sub-addr where t33-sep = "T33S" sub-addr = 1*( DIGIT ) Thus, the minimal specification of a fax in e-mail address is: fax-address = fax-mbox [ "/T33S=" sub-addr ] fax-mbox = "FAX=" global-phone Allocchio Standards Track [Page 2] RFC 2304 Minimal FAX address format March 1998 Note: See section 4.1 in case multiple sub-addr per fax-mbox need to be specified. The Minimal supported syntax for global-phone (as described in section reference [13]) is: global-phone = "+" 1*( DIGIT , written-sep ) written-sep = ( "-" / "." ) The use of other dialling schemas for PSTN numbers (like private numbering plans or local dialling conventions) is also allowed. However, this does not preclude nor remove the minimal compulsory requirement to support the "global-phone" syntax as defined above. Any non "global-phone" dialling schema MUST NOT use the leading "+" between the "=" sign and the dialling string. The "+" sign is strictly reserved for the standard "global-phone" syntax. Note: The specification of these different dialling schemas is out of scope for this minimal specification. User specification of PSTN e-mail addresses will be facilitated if they can insert these separators between dial elements like digits etc. For this reason we allow them in the syntax the written-sep element. Implementors' note: Use of the written-sep elements is allowed, but not recommended. Any occurences of written-sep elements in a pstn-mbox MUST be ignored by all conformant implementations. User Agents SHOULDShow full document text