Internet Engineering Task Force (IETF) R. Atarius
Request for Comments: 8464 September 2018
Category: Informational
ISSN: 2070-1721
A URN Namespace for Device Identity and Mobile Equipment Identity (MEID)
Abstract
This document defines a Uniform Resource Name (URN) namespace for the
Third Generation Partnership Project 2 (3GPP2) and a Namespace
Specific String (NSS) for the Mobile Equipment Identity (MEID). The
structure of an MEID is 15 hexadecimal digits long and is defined in
the 3GPP2 to uniquely identify each individual mobile equipment
(e.g., a handset or mobile phone). The 3GPP2 has a requirement to be
able to use an MEID as a URN. This document fulfills that
requirement.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are candidates for any level of Internet
Standard; see Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8464.
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RFC 8464 MEID-Based URN September 2018
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Namespace Registration Template . . . . . . . . . . . . . . . 4
4. Specification . . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. MEID Parameters . . . . . . . . . . . . . . . . . . . . . 6
4.2. MEID Format . . . . . . . . . . . . . . . . . . . . . . . 6
4.2.1. Overview . . . . . . . . . . . . . . . . . . . . . . 6
4.2.2. Manufacturer Code . . . . . . . . . . . . . . . . . . 6
4.2.3. Serial Number . . . . . . . . . . . . . . . . . . . . 7
4.2.4. Check Digit . . . . . . . . . . . . . . . . . . . . . 7
4.2.5. Hexadecimal Encoding . . . . . . . . . . . . . . . . 7
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
6. Security and Privacy Considerations . . . . . . . . . . . . . 8
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.1. Normative References . . . . . . . . . . . . . . . . . . 9
7.2. Informative References . . . . . . . . . . . . . . . . . 10
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 10
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction
Mobile equipment that is either a) single-mode 3GPP using only 3GPP
technology to transmit and receive voice or data or b) dual-mode
3GPP/3GPP2 using either 3GPP or 3GPP2 technology to transmit and
receive voice or data has an International Mobile station Equipment
Identity (IMEI) to identify it. A URN namespace and an NSS for the
IMEI are defined in [RFC7254]. For cases where the mobile equipment
uses IMEI as an identity for dual-mode 3GPP/3GPP2 access, the IMEI
URN as defined in [RFC7254] can be used to identify the mobile
equipment.
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However, single-mode 3GPP2 mobile equipment that supports only 3GPP2
access technology to transmit and receive voice or data has a
hexadecimal MEID. Since there are fundamental differences between
MEID and IMEI (i.e., in encoding, format, and the ownership),
[RFC7254] cannot be employed to represent the hexadecimal MEID.
This document specifies a URN namespace for 3GPP2 and an NSS for the
MEID as per the namespace registration requirement in [RFC8141]. The
structure of an MEID is 15 hexadecimal digits long and is defined by
3GPP2 (see [S.R0048-A]) to uniquely identify each individual piece of
mobile equipment (e.g., a handset or mobile phone). The 3GPP2 has a
requirement to be able to use an MEID as a URN. This document
fulfills that requirement. The Namespace Identifier (NID) '3gpp2' is
for identities used in 3GPP2 networks. The MEID is managed by the
3GPP2, so this NID is managed by the 3GPP2. This specification
defines only NSSs constructed from MEIDs under the '3gpp2' NID.
These NSSs start with "meid:" in order to identify them as such. In
the future, the 3GPP2 may specify other types of NSSs under the
'3gpp2' NID.
The MEID is 15 hexadecimal digits long, includes a manufacturer code
of 8 hexadecimal digits, and includes the serial number of 6
hexadecimal digits plus a hexadecimal digit as a check digit.
The manufacturer code identifies the mobile equipment manufacturer.
A manufacturer can be assigned more than one manufacturer code. The
serial number uniquely identifies each piece of mobile equipment
within the manufacturer code. The check digit is used as assurance
of integrity in error-prone operations, e.g., when used with certain
types of readers during inventory-management operations. The check
digit is not transmitted. Therefore, the first 14 of the 15
hexadecimal digits are used for defining the MEID as a URN.
The information here is meant to be a concise guide for those wishing
to use the hexadecimal MEID as a URN. Nothing in this document
should be construed to override [S.R0048-A], which defines the MEID.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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RFC 8464 MEID-Based URN September 2018
3. Namespace Registration Template
A completed namespace registration follows.
Namespace Identifier: '3gpp2'
Version: 1
Date: 2018-06-10
Registrant:
Standards Organization: Third Generation Partnership Project 2
(3GPP2)
Contact:
John Derr, MEID Global Hexadecimal Administrator,
JDerr@tiaonline.org
Gary Pellegrino, TIA TR-45 EUMAG Chair, gary@commflowresources.com
c/o Telecommunications Industry Association
1320 N. Courthouse Rd., Suite 200
Arlington, Virginia 22201, United States of America
Purpose: The '3gpp2' namespace is used to identify mobile equipment
that uses technologies defined by the Third Generation Partnership
Project 2 ((3GPP2); initially, such equipment is identified by a
URN that embeds a Mobile Equipment Identity (MEID) that is 15
hexadecimal digits long and unique to each individual piece of
mobile equipment (e.g., a handset or mobile phone).
Syntax: The identifier is expressed in American Standard Code for
Information Interchange (ASCII) characters and has a hierarchical
expression using the Augmented Backus-Naur Form (ABNF) defined in
[RFC5234], as follows:
pp2-urn = "urn:" pp2-NID ":" pp2-NSS
pp2-NID = "3gpp2"
pp2-NSS = meid-specifier / future-pp2-specifier
meid-specifier = "meid:" meidval
future-pp2-specifier = future-specifier *[ ":" 1*( pchar / "/" )]
future-specifier = 1*pp2-char
pp2-char = ALPHA / DIGIT / "-" / "." / "_" /
pct-encoded
where 'pchar' and 'pct-encoded' are defined in [RFC3986]. An NSS
for the MEID is defined under the '3gpp2' NID. The representation
of the MEID is a specific number of hexadecimal digits, as
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described in [S.R0048-A]. The formal definition of a URN with
'meid' NSS contains one meidval with the formal definition
according to the following ABNF [RFC5234]:
meidval = Manufacturer-Code "-" Serial-Number
Manufacturer-Code = 8HEX
Serial-Number = 6HEX
HEX = DIGIT / "A" / "B" / "C" / "D" / "E" / "F"
Assignment: The manufacturer code and serial number portions of the
MEID are permanently stored in the mobile equipment, so they
remain persistent as long as the mobile equipment exists. The
process for manufacturer code and serial number assignment is
documented in [SC.R4002-0] and the manufacturer code and serial
number values once assigned are not reassigned to other pieces of
mobile equipment.
Identifiers in the '3gpp2' namespace are defined and assigned by
the 3GPP2 or an agency appointed by 3GPP2 after ensuring that the
URNs to be assigned are unique. Procedures are in place to ensure
that each MEID is uniquely assigned by the mobile equipment
manufacturer so that it is guaranteed to uniquely identify that
particular piece of mobile equipment.
Security and Privacy: See Section 6 of RFC 8464.
Interoperability: Although both the 3GPP2 Mobile Equipment Identity
(MEID) and the 3GPP International Mobile station Equipment
Identity (IMEI) are used to identify mobile equipment, they are
separate identifiers and are not to be confused.
Internet implementations will not generally possess MEID
identifiers. The identifiers generated by such implementations
will typically be URNs within namespaces other than '3gpp2', and
may, depending on context, even be non-URN URIs. Implementations
are advised to be ready to process URIs other than '3gpp2'
namespace URNs, so as to aid in interoperability.
Resolution: No resolution is envisioned.
Documentation: Documentation can be found in the following
specifications:
* "A URN Namespace for Device Identity and Mobile Equipment
Identity (MEID)" [RFC8464].
* "3G Mobile Equipment Identifier (MEID) - Stage 1" [S.R0048-A].
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* "GHA (Global Hexadecimal Administrator) Assignment Guidelines
and Procedures for Mobile Equipment Identifier (MEID) and Short
Form Expanded UIM Identifier (SF_EUIMID)" [SC.R4002-0].
Additional Information: Because the syntax of a 3GPP2 Mobile
Equipment Identity (MEID) differs from that of a 3GPP
International Mobile station Equipment Identity (IMEI), reuse of
the URN specified in RFC 7254 is not possible.
Revision Information: N/A
4. Specification
4.1. MEID Parameters
Any future change to the format of the 'meid' NSS requires the use of
the procedure for URN NSS changes (currently through the publication
of a future Informational RFC approved by IETF consensus).
[RFC8465] specifies how the MEID URN can be used as an Instance ID as
specified in [RFC5626]. Any change to the Instance ID will require
an update to [RFC8465]. An example of 3GPP2 MEID URN is:
urn:3gpp2:meid:A04B0D56-02A7E3
4.2. MEID Format
4.2.1. Overview
The MEID format is 15 hexadecimal digits encoded in 8 octets as
defined in [S.R0048-A]. The first 8 hexadecimal digits constitute
the manufacturer code; the next 6 hexadecimal digits the serial
number within the manufacturer code. The last hexadecimal digit is a
check digit. For more details on the hexadecimal encoding, see
Section 4.2.5.
4.2.2. Manufacturer Code
The manufacturer code is a value of 8 hexadecimal digits. The
manufacturer code identifies the mobile equipment manufacturer. The
manufacturer code is chosen from a range of values allocated to the
mobile equipment manufacturer in order to uniquely identify the
mobile equipment.
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4.2.3. Serial Number
The serial number is a value of 6 hexadecimal digits. The serial
number identifies equipment within the manufacturer code.
4.2.4. Check Digit
This is a single hexadecimal digit (bits 1-4 of octet 8), and it is
used as assurance of integrity in error-prone operations, e.g., when
used with certain types of readers during inventory management
operations. The check digit is not transmitted by the mobile
equipment and is not used in the MEID URN.
4.2.5. Hexadecimal Encoding
The MEID format is 15 hexadecimal digits encoded in 8 octets as
defined in [S.R0048-A]. The following figure is an abstract
representation of a hexadecimal-encoded MEID stored in memory (the
actual storage format in memory is implementation specific). In this
figure, the most significant digit of the manufacturer code is
encoded in bits 1-4 of octet 1. Bits 5-8 of octet 8 are zero-padded,
since bits 1-4 are only needed to encode the check digit. The most
significant digit of the serial number is encoded in the bits 1-4 of
octet 5. When MEID is included in a cellular signaling message, the
check digit is omitted and the first 7 Octets in the following figure
are only transmitted, [X.S0008-A].
14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Hexadecimal
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ Digits
| | | |
| | | |
| Manufacturer Code | Serial Number |CD|
| | | |
| | | |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
1 2 3 4 5 6 7 8 Octets
5. IANA Considerations
In accordance with BCP 66 [RFC8141], IANA has registered the Formal
URN namespace '3gpp2' in the "Uniform Resource Name (URN) Namespaces"
registry, using the registration template presented in Section 3.
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6. Security and Privacy Considerations
An MEID is usually printed outside of the box in which a mobile
device ships. The MEID may also be printed under the battery on a
mobile device; however, very few devices have removable batteries
today. One can retrieve the MEID via either settings or by dialing
*#06#. Anyone with brief physical access to the mobile device or its
box can easily obtain the MEID. Therefore, MEIDs MUST NOT be used as
security capabilities (identifiers whose mere possession grants
access). Unfortunately, there are currently examples of some
applications that are using the MEID for authorization. Also, some
service providers' customer service departments have been known to
use knowledge of the MEID as "proof" that the caller is the
legitimate owner of the mobile device. Both of these are
inappropriate uses of the MEID.
Since the MEID is permanently assigned to the mobile equipment and is
not modified when the ownership of the mobile equipment changes (even
upon a complete software reload of the mobile equipment), the MEID
URN MUST NOT be used as a user identifier or user address by an
application. Using the MEID to identify a user or as a user address
could result in communications destined for a previous owner of a
device being received by the new device owner or could allow the new
device owner to access information or services owned by the previous
device owner.
Additionally, since the MEID identifies the mobile equipment, it
potentially could be used to identify and track users for the
purposes of surveillance and call data mining if sent in the clear.
Since the MEID is personally identifiable information, uses of the
MEID URN with IETF protocols require a specification and IETF expert
review [RFC8126] in order to ensure that the privacy concerns are
appropriately addressed. Protocols carrying the MEID URN SHOULD, at
a minimum, use strongly hop-by-hop encrypted channels, and it is
RECOMMENDED that end-to-end encryption be used.
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7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122,
DOI 10.17487/RFC4122, July 2005,
<https://www.rfc-editor.org/info/rfc4122>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
[RFC5626] Jennings, C., Ed., Mahy, R., Ed., and F. Audet, Ed.,
"Managing Client-Initiated Connections in the Session
Initiation Protocol (SIP)", RFC 5626,
DOI 10.17487/RFC5626, October 2009,
<https://www.rfc-editor.org/info/rfc5626>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8141] Saint-Andre, P. and J. Klensin, "Uniform Resource Names
(URNs)", RFC 8141, DOI 10.17487/RFC8141, April 2017,
<https://www.rfc-editor.org/info/rfc8141>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[S.R0048-A]
3GPP2, "3G Mobile Equipment Identifier (MEID) - Stage 1,
Version 4.0", Stage 1, Version 4.0, 3GPP2 S.R0048-A, June
2005, <http://www.3gpp2.org/Public_html/specs/
S.R0048-A_v4.0_050630.pdf>.
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[SC.R4002-0]
3GPP2, "GHA (Global Hexadecimal Administrator) Assignment
Guidelines and Procedures for Mobile Equipment Identifier
(MEID) and Short Form Expanded UIM Identifier
(SF_EUIMID)", 3GPP2 TS SC.R4002-0, Version 12.0, December
2016, <http://www.3gpp2.org/Public_html/Specs/SC.R4002-0_v
12.0_GHA_%20Guidelines_for_MEID_December_2016.pdf>.
[X.S0008-A]
3GPP2, "MAP Support for the Mobile Equipment Identity
(MEID)", 3GPP2 TS X.S0008-A, Version 2.0, March 2014,
<http://www.3gpp2.org/Public_html/Specs/
X.S0008-A_v2.0_20140321.PDF>.
7.2. Informative References
[RFC7254] Montemurro, M., Ed., Allen, A., McDonald, D., and P.
Gosden, "A Uniform Resource Name Namespace for the Global
System for Mobile Communications Association (GSMA) and
the International Mobile station Equipment Identity
(IMEI)", RFC 7254, DOI 10.17487/RFC7254, May 2014,
<https://www.rfc-editor.org/info/rfc7254>.
[RFC8465] Atarius, R., Ed., "Using the Mobile Equipment Identity
(MEID) URN as an Instance ID", RFC 8465,
DOI 10.17487/RFC8465, September 2018,
<https://www.rfc-editor.org/info/rfc8465>.
Acknowledgements
This document draws heavily on the 3GPP2 work on Numbering,
Addressing, and Identification in [S.R0048-A] and also on the style
and structure used in [RFC7254] and [RFC4122].
The author thanks Ramachandran Subramanian, Alex Gogic, Randall
Gellens, and Peter Saint-Andre for detailed comments.
Author's Address
Roozbeh Atarius
Email: ratarius@motorola.com
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