Network Working Group M. Riegel
Request for Comments: 3017 Siemens AG
Category: Standards Track G. Zorn
Cisco Systems
December 2000
XML DTD for Roaming Access Phone Book
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 (2000). All Rights Reserved.
Abstract
This document defines the syntax as well as the semantics of the
information to be included in the phone book for roaming
applications. It comprises the information necessary to select the
most appropriate ISP and to configure the host to get access to the
network of the provider. The specification consists of a small set of
required information elements and a variety of possible extensions.
All data is specified in XML [5] (Extensible Markup Language) syntax
leading to a concise XML DTD (Document Type Declaration) for the
phone book.
Table of Contents
1. Introduction ............................................. 3
2. Rationale for XML Usage .................................. 4
3. Specification of Requirements ............................ 5
4. Value type notations for 'stronger' typing ............... 5
5. Container Element Definitions ............................ 5
5.1. PhoneBook ............................................ 5
5.1.1. phoneBook Attribute "name" ........................ 6
5.1.2. phoneBook Attribute "version" ..................... 6
5.2. POP .................................................. 7
5.2.1. pop Attribute "entryVersion" ...................... 8
5.3. Setup ................................................ 8
5.4. Support .............................................. 9
5.5. Provider ............................................. 9
Riegel & Zorn Standards Track [Page 1]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
6. Information Element Definitions .......................... 10
6.1. Information elements defined for the POP element ..... 10
6.1.1. Address ........................................... 10
6.1.1.1. address Attribute "family" ..................... 10
6.1.1.2. address Attribute "countryCode" ................ 11
6.1.1.3. address Attribute "areaCode" ................... 11
6.1.2. Media ............................................. 11
6.1.2.1. Modem Protocols ................................ 12
6.1.2.2. ISDN Protocols ................................. 12
6.1.2.3. ATM Protocols .................................. 13
6.1.2.4. Frame Relay Protocols .......................... 13
6.1.2.5. X.25 Protocols ................................. 13
6.1.3. Minimum Data Rate ................................. 14
6.1.4. Maximum Data Rate ................................. 14
6.1.5. POP Properties .................................... 14
6.1.6. Tunneling Protocols ............................... 15
6.1.7. Dialing Script .................................... 15
6.1.8. Pricing Information ............................... 16
6.1.9. City .............................................. 16
6.1.10. Region ........................................... 16
6.1.11. Country .......................................... 16
6.1.12. POP Setup ........................................ 17
6.1.13. POP Support ...................................... 17
6.1.14. POP Provider ..................................... 17
6.2. Information elements defined for the Setup element ... 17
6.2.1. DNS Server Address ................................ 17
6.2.2. NNTP Server Name .................................. 18
6.2.3. SMTP Server Name .................................. 18
6.2.4. POP3 Server Name .................................. 18
6.2.5. IMAP Server Name .................................. 18
6.2.6. WWW Proxy ......................................... 19
6.2.7. FTP Proxy ......................................... 19
6.2.8. Winsock Proxy ..................................... 19
6.2.9. Default Gateway Address ........................... 19
6.2.10. User Name Suffix ................................. 20
6.2.11. User Name Prefix ................................. 20
6.3. Information elements defined for the support element.. 20
6.3.1. Support Telephone Number .......................... 20
6.3.2. Support Email Address ............................. 21
6.4. Information elements defined for the provider element. 21
6.4.1. Provider Name ..................................... 21
6.4.2. Provider Icon ..................................... 21
6.4.3. Provider's World Wide Web URL ..................... 21
6.4.4. Provider's Main Email Address ..................... 22
6.4.5. Billing Inquiry Email Address ..................... 22
6.4.6. Further elements .................................. 22
7. Complete XML DTD for the roaming phone book .............. 22
8. Security Considerations .................................. 28
Riegel & Zorn Standards Track [Page 2]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
9. IANA Considerations ...................................... 28
9.1. Registration of new attribute values ................. 29
9.2. Registration of new information elements ............. 29
10. References .............................................. 30
11. Appendix: Examples ...................................... 31
11.1. The most simple example ............................. 31
11.2. A more comprehensive example ........................ 31
12. Acknowledgments ......................................... 31
13. Authors' Addresses ...................................... 32
14. Full Copyright Statement ................................ 33
1. Introduction
Roaming applications depend on the delivery of information about
provided services and the procedures to get connected to the network
from the roaming consortium to the individual users as well as from
the operators of the network access servers, normally the members of
the roaming consortium, and the roaming consortium.
"phone book"
+------+ +--+
| | | ++
| ISP1 | -- | | --+
| | +---+ \ "phone book"
+------+ \ +------+
+------+ +--+ \_ | | +--+ +------+
| | | ++ | | | ++ | |
| ISP2 | -- | | -->>--- | | --- | | ->> | USER |
| | +---+ _ | | +---+ | |
+------+ / | | +------+
+------+ +--+ / +------+
| | | ++ / Roaming
| ISP# | -- | | --+ Consortium
| | +---+
+------+
The roaming consortium assembles from the individual contributions of
the providers belonging to the consortium a unified version of the
phone book for usage by the customers. Probably different groups of
users get different versions of a phone book adapted to their
particular needs. Even users might generate different subsets
especially suited to particular applications from the information
received from the roaming consortium, e.g., retrieving only entries
for a particular country or extracting all access points providing
wireless connectivity.
Riegel & Zorn Standards Track [Page 3]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Therefore it is desirable to define a highly portable and well formed
structure of the phone book to enable easy generation and
postprocessing. Goals of this document include:
- Creating a flexible, extensible and robust framework
upon which to build a standard phone book;
- Promoting a standard phone book format, to enhance
interoperability between ISPs and roaming consortia as
well as to enable automatic extraction of configuration
data by a wide variety of devices;
- Defining a compact structure containing the essential
information for the roaming user, to allow for storage
and easy update even on small devices.
It is not intended by this document to create a plethoric solution,
with phone book elements to fit every condition on earth, neither to
define any kind of phone book update or transfer protocol.
2. Rationale for XML Usage
XML is rapidly becoming a standard format for data exchange between
different applications also taking into account the transfer and
access of data over the web. XML is used as syntax for expressing
the structure and content of a roaming phone book to enable
widespread usage and access to many different kind of media (e.g.,
paper, CDROM, www) using a widespread selection of access devices.
Furthermore XML enables:
- Extensibility
- Flexibility
- Integration with directories
Extensibility is important because phone books are living documents;
as such, it is unlikely that all the semantic requirements of
arbitrary Internet service providers (ISPs) would be met by a fixed
scheme, no matter how well thought out. Phone book designers must be
free to create new attributes in a well-understood fashion to meet
changing business needs.
Flexibility is required of the attribute definition syntax for many
of the same reasons that semantic extensibility is necessary. If we
assume that phone book designers may need to define elements of
arbitrary type, the syntax chosen must be able to represent these
data objects cleanly. Using XML for describing the data content of
the phone book fits this bill nicely, since it can be used to
unambiguously describe virtually any data type.
Riegel & Zorn Standards Track [Page 4]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Integration with directories: although it is unlikely that phone
books will be stored in the directory due to performance
considerations, the creation of a XML DTD describing phone book
content leaves that option open, with relatively little incremental
effort required to implement it.
3. Specification of Requirements
In this document, the key words "MAY", "MUST, "MUST NOT", "optional",
"recommended", "SHOULD", and "SHOULD NOT", are to be interpreted as
described in [1].
4. Value type notations for 'stronger' typing
XML DTDs do not currently have capabilities for 'strong typing' of
the content of elements. The only type definition foreseen in the
base specification is "#PCDATA", 'parsable character data'. This
might be sufficient and is used throughout this document to define
elements containing information mainly aimed for interpretation by
human beings.
To enable a more concise description of the content of particular
elements several value type notations are introduced. This allows
for a more detailed type description of the content of elements in
cases where it seems to be desirable.
5. Container Element Definitions
5.1. PhoneBook
The phoneBook element is the basic container for phone book entries.
It has two attributes, a phone book name and a phone book version
number (applying to the phone book as a whole), and always contains
one or more pop elements. A phoneBook element may also contain
multiple Setup, Support and Provider elements, if they are referenced
to by more than one pop element.
Riegel & Zorn Standards Track [Page 5]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Syntax:
phoneBook
+-----------------------------------+
| phoneBookName (req)|
| phoneBookVersion (req)|
| +-----------------------+ |
| | pop |+ (req)|
| +-----------------------+| |
| + - - - - - - - - - - - + |
| |
| + - - - - - - - - - - - + |
| | setup |+ (opt)|
| + - - - - - - - - - - - +| |
| + - - - - - - - - - - - + |
| |
| + - - - - - - - - - - - + |
| | support |+ (opt)|
| + - - - - - - - - - - - +| |
| + - - - - - - - - - - - + |
| |
| + - - - - - - - - - - - + |
| | provider |+ (opt)|
| + - - - - - - - - - - - +| |
| + - - - - - - - - - - - + |
+-----------------------------------+
5.1.1. phoneBook Attribute "name"
The phoneBook attribute "name" is an arbitrary string assigned as an
identifier for a phone book.
5.1.2. phoneBook Attribute "version"
The phoneBookVersion attribute is an integer representing the version
of the phone book; it is a monotonically increasing counter which
should be incremented each time the phone book is modified. This
element can be used by a server to help decide what (if any) actions
are required to bring a client's phone book up to date. For example,
the client can, at connect time, send an update request to the server
Riegel & Zorn Standards Track [Page 6]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
including in the request the version number of its current phone
book. If the client's phone book version is not the same as the
server's current phone book version, the server can easily take
appropriate action, e.g., reply with a URL pointing to a file
containing the differences between the client and server phone books.
5.2. POP
The pop element contains information elements relevant to individual
network points of presence (POPs). The required information elements
are addrFamily, address, media and entryVersion. The media element
represents the media types supported by the POP, while the
entryVersion element is a monotonically-increasing integer which
should be incremented whenever the object is modified.
The following information elements are currently defined for the pop
element. Additional information elements may be defined by IANA in
future.
POP
+-----------------------------------+
| entryVersion (req)|
| +-------------------------+ |
| | address | (req)|
| +-------------------------+ |
| media (req)|
| minBitsPerSecond (opt)|
| maxBitsPerSecond (opt)|
| "popProperties" (opt)|
| "tunnelingProtocols" (opt)|
| dialScript (opt)|
| pricingInformation (opt)|
| + - - - - - - - - - - - - + |
| | "location" | (opt)|
| + - - - - - - - - - - - - + |
| + - - - - - - - - - - - - + |
| | "popSetup" | (opt)|
| + - - - - - - - - - - - - + |
| + - - - - - - - - - - - - + |
| | "popSupport" | (opt)|
| + - - - - - - - - - - - - + |
| + - - - - - - - - - - - - + |
| | "popProvider" | (opt)|
| + - - - - - - - - - - - - + |
+-----------------------------------+
Riegel & Zorn Standards Track [Page 7]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Syntax:
5.2.1. pop Attribute "entryVersion"
The entryVersion attribute is an integer representing the version of
the POP object; it is a monotonically increasing counter which should
be incremented each time the object is modified. This attribute may
be useful in merging and updating phone books.
5.3. Setup
The Setup element includes information elements which describe
services which may change from provider to provider or even from POP
to POP. Some of the values contained in these information elements
may be available by other means (e.g., DHCP), but others may not.
The following information elements are currently defined for the
Setup element. Additional information elements may be defined by
IANA in future.
Syntax:
5.4. Support
The Support element includes those information elements that are
pertinent to the provision of customer support for a POP or provider.
Languages spoken by the staff at the support center might be
specified by multiple entries for the attribute value language.
Additional information elements for the Support element may be
defined by IANA in future.
Syntax:
5.5. Provider
The Provider element contains information elements pertaining to the
general business operations of a given network service provider. The
information elements include such things as telephone number, mailing
address, etc., as well as URLs for e-mail and a World Wide Web site.
A Provider element may also contain a reference to support
information.
Currently the following information elements are defined for the
Provider element. Additional information elements may be defined by
IANA in future.
Syntax:
6. Information Element Definitions
6.1. Information elements defined for the POP element
6.1.1. Address
The address element provides the information representing the address
of the POP. For POPs offering dial-up network access, the address
element will at least contain an IA5 string representing a telephone
number, formatted in standard fashion [4] (e.g., "+ 1 234 5678").
More detailed information may be available by optional attribute
values.
Syntax:
6.1.1.1. address Attribute "family"
The attribute family of the element address defines the address
family to which the element value belongs. For POPs offering dial-up
network access, the addrFamily attribute will generally contain a
value for a telephone network based address family. Currently the
following attribute values are defined. Additional values may be
Riegel & Zorn Standards Track [Page 10]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
registered by IANA in future.
Value Description
------ ------------------------------------------
E164 ITU-T E.164 (PSTN, SMDS, Frame Relay, ATM)
X121 ITU-T X.121 (X.25, Frame Relay)
Syntax:
6.1.1.2. address Attribute "countryCode"
The countryCode attribute indicates the international dialing prefix
for the country in which the POP is located.
Syntax:
6.1.1.3. address Attribute "areaCode"
The areaCode attribute contains the area or city code component of
the telephone number in the 'address' element (if any) associated
with this POP.
6.1.2. Media
The media element is a container describing the types of media and
related protocols supported by this POP. The following media types
are currently defined. Additional types may be registered by IANA in
future.
Value Media Type
-------- -----------
viaMODEM Modem
viaISDN ISDN
viaATM ATM
viaFR Frame Relay
viaX25 X.25
Riegel & Zorn Standards Track [Page 11]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Syntax:
6.1.2.1. Modem Protocols
The viaMODEM element is an empty element representing by its optional
type attribute the modem protocol supported by the access devices
that can be reached at address. To define multiple available
protocols this element may be included repeatedly. The initially
defined modem protocol types are listed in the table below.
Additional values may be registered by IANA in future.
Value Duplex Speed Protocol
----- ------ ----- -------------
V21 Full 300 ITU-T V.21
V22 Full 1200 ITU-T V.22
V29 Half 9600 ITU-T V.29
V32 Full 9600 ITU-T V.32
V32B Full 14.4k ITU-T V.32bis
V34 Full 28.8k ITU-T V.34
V34B Full 33.6k ITU-T V.34bis
V90 Full 56k ITU-T V.90
Syntax
6.1.2.2. ISDN Protocols
The viaISDN element is an empty element representing by its optional
type attribute the ISDN protocol supported by the access devices that
can be reached at address. To define multiple available protocols
this element may be included repeatedly. The initially defined ISDN
protocol types are listed in the table below. Additional values may
be registered by IANA in future.
Value Speed Meaning
----- ----- -----------
V110L 19.2k ITU-T V.110
V110H 38.4k ITU-T V.110
V120L 56k ITU-T V.120
Riegel & Zorn Standards Track [Page 12]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
V120H 64k ITU-T V.120
X75 64k ITU-T X.75
HDLC 64k RFC 1618
Syntax:
6.1.2.3. ATM Protocols
The viaATM element is an empty element representing by its optional
type attribute a particular protocol supported by the access devices
that can be reached at address. To define multiple available
protocols this element may be included repeatedly. Currently only
one protocol is defined. Additional values may be registered by IANA
in future.
Syntax:
6.1.2.4. Frame Relay Protocols
The viaFR element is an empty element representing by its optional
type attribute the particular protocol supported by the access
devices that can be reached at address. To define multiple available
protocols this element may be included repeatedly. Currently only
one protocol is defined. Additional values may be registered by IANA
in future.
Syntax:
6.1.2.5. X.25 Protocols
The viaX25 element is an empty element representing by its optional
type attribute the particular protocol supported by the access
devices that can be reached at address. To define multiple available
Riegel & Zorn Standards Track [Page 13]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
protocols this element may be included repeatedly. Currently only
one protocol is defined. Additional values may be registered by IANA
in future.
Syntax:
6.1.3. Minimum Data Rate
The minBitsPerSecond element indicates the minimum data rate (in
bits/second) supported by the access devices at the POP.
Syntax:
6.1.4. Maximum Data Rate
The maxBitsPerSecond element indicates the maximum data rate (in
bits/second) supported by the access devices at the POP.
Syntax:
6.1.5. POP Properties
The popProperty element is an empty element representing by its
attribute value a particular property of this POP. To define
multiple available protocols this element might be included several
times. The initially defined properties are listed in the table
below. Additional values may be registered by IANA in future.
Value Property
------ ----------------------
MPPP Multilink PPP (RFC 1990)
MOBIP Mobile IP (RFC 2002)
MCRX Multicast Reception
MCTX Multicast Transmission
Syntax:
Riegel & Zorn Standards Track [Page 14]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
6.1.6. Tunneling Protocols
The tunnelProto element is an empty element representing by its
attribute a tunneling protocol supported by this POP. To define
multiple available protocols this element might be included several
times. The initially defined values are listed in the table below.
Additional values may be registered by IANA in future.
Value Protocol
------ ------------------
L2TP RFC 2661 L2TP
PPTP RFC 2637 PPTP
L2F RFC 2341 L2F
ATMP RFC 2107 ATMP
AHT RFC 2402 IP AH Tunnel Mode
ESPT RFC 2406 IP ESP Tunnel Mode
IPIP RFC 1853 IP-IP
MIP RFC 2004 Minimal IP-IP
GRE RFC 1701 GRE
Syntax:
6.1.7. Dialing Script
The dialScript element contains the dialing script to be used when
connecting to this POP. The attribute value type of dialScript
defines the type of the script that should be used when connecting to
this POP.
Syntax:
Riegel & Zorn Standards Track [Page 15]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
6.1.8. Pricing Information
The pricingInformation element is a free-form string representing
pricing information for this POP. It may be anything from a simple
string indicating relative expense (e.g., "$$$$" for a very expensive
POP) to a paragraph describing time-of-day and other differential
pricing variables.
Syntax:
6.1.9. City
The city element contains the name of the city in which the POP is
located (not the city(s) from which it is accessible by a local
call).
Syntax:
6.1.10. Region
The region element contains the name of the region in which the POP
is located. In the United States, this would be the name of a state
or (for Washington, D.C.) administrative district. In other
countries, it might be the name of a province, parish or county.
Syntax:
6.1.11. Country
The country element contains the name of the country in which the POP
is located. The country name may be abbreviated (e.g., "USA" for the
United States of America or "UK" for the United Kingdom) but if
abbreviations are used the usage must be consistent within a given
phone book.
Syntax:
Riegel & Zorn Standards Track [Page 16]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
6.1.12. POP Setup
The popSetup element is either a setup element, if setup is specific
to this particular POP, or a reference to any of the setup elements
given in the outer scope of the phonebook element.
Syntax:
6.1.13. POP Support
The popSupport element is either a support element, if support is
specific to this particular POP, or a reference to any of the support
elements given in the outer scope of the phonebook element.
Syntax:
6.1.14. POP Provider
The popProvider element is either a provider element, if provider
information is specific to this particular POP, or a reference to any
of the provider elements given in the outer scope of the phonebook
element.
Syntax:
6.2. Information elements defined for the Setup element
6.2.1. DNS Server Address
The dnsServerAddress element represents the IP address of the Domain
Name Service (DNS) server which should be used when connected to this
POP. The address is represented in the form of a string in dotted-
decimal notation (e.g., 192.168.101.1).
Riegel & Zorn Standards Track [Page 17]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Syntax:
6.2.2. NNTP Server Name
The nntpServerName element contains the fully qualified domain name
(FQDN) of the Network News Transfer Protocol (NNTP) server which
should be used when connected to this POP.
Syntax:
6.2.3. SMTP Server Name
The smtpServerName element contains the FQDN of the Simple Mail
Transfer Protocol (SMTP) server which should be used when connected
to this POP.
Syntax:
6.2.4. POP3 Server Name
The popServerName element contains the FQDN of the Post Office
Protocol (POP) server which should be used when connected to this
POP.
Syntax:
6.2.5. IMAP Server Name
The imapServerName element contains the FQDN of the Internet Mail
Access Protocol (IMAP) server which should be used when connected to
this POP.
Riegel & Zorn Standards Track [Page 18]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Syntax:
6.2.6. WWW Proxy
The wwwProxyServerName element contains the FQDN of the World Wide
Web (WWW) proxy server which should be used when connected to this
POP.
Syntax:
6.2.7. FTP Proxy
The ftpProxyServerName element contains the FQDN of the File Transfer
Protocol (FTP) proxy server which should be used when connected to
this POP.
Syntax:
6.2.8. Winsock Proxy
The winsockProxyServerName element contains the FQDN of the Windows
Socket (Winsock) proxy server which should be used when connected to
this POP.
Syntax:
6.2.9. Default Gateway Address
The defaulttGatewayAddress element represents the address of the
default gateway which should be used when connected to this POP. The
address is represented in the form of a string in dotted-decimal
notation (e.g., 192.168.101.1).
Riegel & Zorn Standards Track [Page 19]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Syntax:
6.2.10. User Name Suffix
The userNameSuffix element represents a string which should be
concatenated to the base username. For example, if the base username
is "userA" and the value of this element is "@bigco.com", the
resulting augmented username would be "userA@bigco.com". An
intelligent dialer may concatenate the string automatically. Note
that both the userNameSuffix and the userNamePrefix (below) may be
applied to the same base username.
Syntax:
6.2.11. User Name Prefix
The userNamePrefix element represents a string to which the base
username should be concatenated. For example, if the base username
is "userB" and the value of this element is "BIGCO/" the resulting
augmented username would be "BIGCO/userB". An intelligent dialer may
perform the concatenation automatically. Note that both the
userNameSuffix (above) and the userNamePrefix may be applied to the
same base username.
Syntax:
6.3. Information elements defined for the support element
6.3.1. Support Telephone Number
The supportTelephoneNumber element contains a number that may be
called to reach the support center for a particular provider or POP.
This element is basically a string and should contain the entire
telephone number in international form, e.g., "+1 425 838 8080".
Syntax:
Riegel & Zorn Standards Track [Page 20]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
6.3.2. Support Email Address
The supportMailtoURL element contains a URL for the provider's
customer support email address, e.g., mailto:support@uu.net. This
URL could be used to contact customer support personnel regarding
non-urgent issues.
Syntax:
6.4. Information elements defined for the provider element
6.4.1. Provider Name
The providerName element is a string containing the name of the
provider (e.g., "BIGNET Corporation").
Syntax:
6.4.2. Provider Icon
The providerIcon attribute contains a BASE64 encoded JPEG or GIF
image which may be used for 'branding' phone book entries or
displayed when dialing.
Syntax:
6.4.3. Provider's World Wide Web URL
The wwwURL element contains a Uniform Resource Locator (URL) for the
provider's Web site, for example, http://www.uu.net.
Syntax:
Riegel & Zorn Standards Track [Page 21]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
6.4.4. Provider's Main Email Address
The generalMailtoURL element contains a URL for the provider's main
email address, for example, mailto:contact@uu.net. This URL could be
used for general correspondence, complaints, etc.
Syntax:
6.4.5. Billing Inquiry Email Address
The billingMailtoURL element contains a URL for the provider's
billing support email address, for example, mailto:billing@uu.net.
This URL could be used to for correspondence regarding billing and
payment issues.
Syntax:
6.4.6. Further elements
The remainder of the information elements of the provider element are
described in principle in [3].
7. Complete XML DTD for the roaming phone book
Riegel & Zorn Standards Track [Page 22]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Riegel & Zorn Standards Track [Page 24]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Riegel & Zorn Standards Track [Page 25]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Riegel & Zorn Standards Track [Page 26]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
Riegel & Zorn Standards Track [Page 27]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
8. Security Considerations
The secure distribution and transport of information of a phone book
for roaming applications require a reliable authentication of the
issuer of the information as well as means to preserve the integrity
of the provided information.
No specific elements for security requirements are provided by the
phone book XML DTD itself. It is assumed that security of the
roaming phone book is provided by means outside of the scope of this
specification, such as signing the phone book using pgp.
9. IANA Considerations
This specification provides the possibility to define further
attribute values for all information elements owning enumerated
attribute lists as well as to extend the main structures 'pop',
'setup', 'support' and 'provider' by additional information elements.
Therefore the specification of the roaming phone book can be adopted
to future requirements without changing this document. Extensions
and refinements to this specification can be achieved by registration
of new elements and attributes by IANA.
Extending this specification with additional attributes or elements
must not change the validity of documents based on an older version
of the XML DTD. Therefore all added information elements must be
Riegel & Zorn Standards Track [Page 28]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
optional, prohibiting the mandatory inclusion of newly defined
information elements. Adding new values to enumerated attribute
lists has no backward compatibility constraints because it does not
harm the validity of attributes already defined.
To facilitate the registration of new information elements and
attribute values the DTD of the phone book has been separated in two
parts, the extensible part containing only parameter entity
declarations for ease inclusion of new values, and the fixed part
containing the detailed specification of the content and structure of
the phone book. By referencing the parameter entity declarations in
the fixed part of the specification the whole phone book becomes
extensible.
The part containing the parameter entity declarations has to be
maintained by the IANA. There are two different classes of
declarations in this part requiring different policies for
registering new values.
9.1. Registration of new attribute values
The entities 'addressFamily', 'modemProtocols', 'isdnProtocols',
'atmProtocols', 'frProtocols', 'x25Protocols', 'popProperties' and
'tunnelingProtocols' are describing enumerated attribute value lists.
Because there is no limitation in the name space of these attribute
values and newly defined attribute values can not harm the validity
of existing values, new attribute values can be assigned by
Specification Required [6].
9.2. Registration of new information elements
The entities 'mediaTypes', 'popInformation', 'setupInformation', '
supportInformation' and 'providerInformation' define the information
elements probably included in the media, pop, setup, support and
provider elements. Inserting new values into these lists extends the
phone book by arbitrarily new information elements. Inappropriate
use of the XML content model can destroy the backward compatibility
of the DTD. Therefore the assignment of new information elements
requires the approval of a Designated Expert [6]. In addition to the
insertion of a new value into the list, the detailed definition of
the information element has to be appended to the specification part
maintained by the IANA.
Riegel & Zorn Standards Track [Page 29]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
10. References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
[2] Reynolds, J. and J. Postel, "ASSIGNED NUMBERS", STD 2, RFC 1700,
October 1994.
[3] Barker, P. and S. Kille, "The COSINE and Internet X.500 Schema",
RFC 1274, November 1991.
[4] ITU Rec. E.123, "Notation for national and international
telephone numbers", 1988.
[5] "Extensible Markup Language (XML) 1.0" W3C Recommendation 10-
February-1998 http://www.w3.org/TR/1998/REC-xml-19980210
[6] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA
Considerations Section in RFCs", BCP 26, RFC 2434, October 1998.
Riegel & Zorn Standards Track [Page 30]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
11. Appendix: Examples
11.1. The most simple example
+1 234 5678901
11.2. A more comprehensive example
+49913130540
192.168.147.5
193.175.24.33
mailto:support@franken.de
+499123968066
12. Acknowledgments
Thanks to Pat Calhoun, Bernard Aboba, Jay Farhat, Butch Anton,
Quentin Miller, and Ken Crocker for salient input and review.
Riegel & Zorn Standards Track [Page 31]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
13. Authors' Addresses
Questions about this memo can be directed to:
Max Riegel
Siemens AG
Hofmannstr. 51
Munich, 81359
Germany
Phone: +49 89 722 49557
EMail: maximilian.riegel@icn.siemens.de
Glen Zorn
Cisco Systems, Inc.
500 108th Avenue N.E., Suite 500
Bellevue, WA 98004
USA
Phone: +1 425 438 8218
EMail: gwz@cisco.com
Riegel & Zorn Standards Track [Page 32]
RFC 3017 Roaming Access Phone Book XML DTD December 2000
14. Full Copyright Statement
Copyright (C) The Internet Society (2000). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
Riegel & Zorn Standards Track [Page 33]
RFC, FYI, BCP