RFC 4143

Facsimile Using Internet Mail (IFAX) Service of ENUM

📅 published November 2005, from ietf

RFC 4143: Facsimile Using Internet Mail (IFAX) Service of ENUM 📠✨

Okay bestie, here's the deal 💖 This is RFC 4143, a Standards Track doc from November 2005. The authors are K. Toyoda (PCC) and D. Crocker (Brandenburg) 🎀 It doesn't list any obsoletes or updates, so it isn't replacing or changing anything else.

Status of This Memo 🌸

This document is an Internet standards track protocol for the Internet community, and it's asking for discussion and suggestions for improvements 💅 For the standardization state and status of this protocol, check the current edition of the "Internet Official Protocol Standards" (STD 1). Distribution of this memo is unlimited 🦋

Copyright Notice 🌈

Abstract ✨

This doc describes the functional spec and definition of the ENUM Naming Authority Pointer (NAPTR) record for IFax service 🧚 IFax means "facsimile using Internet mail" 📠 For this use, the Domain Name System (DNS) returns the email address of the IFax system you're trying to reach. So the sender doesn't need to already know the recipient's email address, they can just use a telephone number 🙈 It's giving email-based fax communication with phone numbers, iconic 🔥

1. Functional Specification 💜

An IFax client makes a [ENUMbis] DNS query using the target system's telephone number 📞 The NAPTR record that comes back specifies an email address to use for reaching that system. Then that email address gets used under Simple Mode of Facsimile using Internet Mail [RFC3965], Extended Facsimile using Internet Mail [RFC2532], or Full Mode Fax Profile for Internet Mail [FFPIM], whichever one applies 🫶

The key words "MUST", "MUST NOT", "SHOULD", "SHOULD NOT", and "MAY" in this document are to be interpreted as defined in "Key words for use in RFCs to Indicate Requirement Levels" [KEYWORDS] 🎀

2. IFax Service Registration 📋

Here's the registration info, verbatim:

Service Name : "E2U+ifax"

Type: "ifax"

Subtype: "mailto"

URI Scheme: "mailto"
The URI Scheme is "mailto" because facsimile is a profile of standard
Internet mail and uses standard Internet mail addressing.

Functional Specification: See section 1

Security Considerations: See section 3

Intended usage: COMMON

Author: Kiyoshi Toyoda (toyoda.kiyoshi@jp.panasonic.com)
        Dave Crocker (dcrocker@bbiw.net)

The URI scheme is mailto because faxing here is just a profile of normal Internet mail, so it uses standard Internet mail addressing 💌 Ngl that's so clean 🍓

3. Security Considerations 🚨💀

Okay, this section is serious, so read it closely 👀 DNS, which ENUM uses, is a globally distributed database. That means anything stored in it is visible to anyone, anonymously 🌍 Yes, it's not that different from a phone directory, BUT it does expose the data to automatic data collection, with no indication that it's happening or who's doing it 😭

Third parties often harvest data to build lists of targets for unrequested information. Basically, those lists get used to target "spam" 📧 Publishing a phone number in ENUM, especially when it's tied to an Internet fax service, may be used to send "junk faxes," for example 📠💀

With email, people on mailing lists can have "sacrificial" accounts. These special-purpose addresses help users filter out unrequested email 🙌 That's not so easy with published phone numbers. The PSTN E.164 number assignment process is much more involved and less flexible. Usually one E.164 number (or a fixed range of numbers) is tied to each PSTN access. So you can't really use a "sacrificial" phone number 🥲

Because publishing data in a globally accessible database has these implications, the data subject MUST give explicit informed consent to data being published in ENUM. This one is non-negotiable 🛑

Internet Fax is based on existing use of Internet mail. Developers and users should also consider the Security Consideration sections in [RFC3965] and [RFC2532].

In addition to the specific security considerations above, the Security Considerations section of [ENUMbis] applies to this document too 🔐

4. Example 🧚

Here's an example of IFax service in a NAPTR record:

$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa
  IN NAPTR 10 10 "u" "E2U+ifax:mailto"
                         "!^.*$!mailto:toyo@example.com!"

5. IANA Considerations 🌷

This spec creates a DNS NAPTR registration, following the terms specified in [ENUMbis]. The registration details are in section 2, Fax Service Registration 📋

6. References 📚

6.1. Normative References 💜

[KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate
           Requirement Levels", BCP 14, RFC 2119, March 1997.

[ENUMbis]  Faltstrom, P. and M. Mealling, "The E.164 to Uniform
           Resource Identifiers (URI) Dynamic Delegation Discovery
           System (DDDS) Application (ENUM)", RFC 3761, April 2004.

[RFC3965]  Toyoda, K., Ohno, H., Murai, J., and D. Wing, "A Simple
           Mode of Facsimile Using Internet Mail", RFC 3965, December
           2004.

[RFC2532]  Masinter, L. and D. Wing, " Extended Facsimile Using
           Internet Mail", RFC 2532, March 1999.

[FFPIM]    Crocker, D. and G. Klyne, "Full-mode Fax Profile for
           Internet Mail (FFPIM)", RFC 4142, November 2005.

Authors' Addresses 🏠

Kiyoshi Toyoda
Research and Development Laboratory
Panasonic Communications Co., Ltd.
4-1-62 Minoshima Hakata-ku, Fukuoka 812-8531 Japan

Phone: +81-50-3380-5181
EMail: toyoda.kiyoshi@jp.panasonic.com


Dave Crocker
Brandenburg InternetWorking
675 Spruce Drive
Sunnyvale, CA  94086  USA

Phone: +1.408.246.8253
EMail: dcrocker@bbiw.net

Full Copyright Statement 🌈

This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights.

This is the legal disclaimer, kept word for word 🫶

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Acknowledgement 💖

Funding for the RFC Editor function is currently provided by the Internet Society ✨

📦 where this page comes from

ietf: rfc4143 2005-11
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