ENUM J. Ra Internet-Draft S. Shin Expires: January 18, 2006 Y. Ju W. Kim NIDA L. Conroy Roke Manor Research July 17, 2005 IANA Registration for Enumservice Mobile Webpage Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on January 18, 2006. Copyright Notice Copyright (C) The Internet Society (2005). Abstract This document registers the ENUMservice "mobileweb" using the URI schemes 'http:' and 'https:' as per the IANA registration process defined in the ENUM specification RFC3761. Ra, et al. Expires January 18, 2006 [Page 1] Internet-Draft Mobileweb Enumservice Registration July 2005 Table of Contents 1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Current Status of Mobile Web Services . . . . . . . . . . . . 6 4. Mobile Web Service Registration . . . . . . . . . . . . . . . 9 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . 9 4.2 Diverse Mobile Web Service Registration with 'http:','https:' . . . . . . . . . . . . . . . . . . . . . 10 4.3 Uniform Mobile Web Service Registration with 'http:','https:' . . . . . . . . . . . . . . . . . . . . . 10 5. Considerations for the 'WAP' registration . . . . . . . . . . 12 6. Expected Behaviour . . . . . . . . . . . . . . . . . . . . . . 13 7. Security Considerations . . . . . . . . . . . . . . . . . . . 15 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18 9.1 Normative References . . . . . . . . . . . . . . . . . . . 18 9.2 Informative References . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 19 Intellectual Property and Copyright Statements . . . . . . . . 21 Ra, et al. Expires January 18, 2006 [Page 2] Internet-Draft Mobileweb Enumservice Registration July 2005 1. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, RFC2119 [1]. Ra, et al. Expires January 18, 2006 [Page 3] Internet-Draft Mobileweb Enumservice Registration July 2005 2. Introduction ENUM (E.164 Number Mapping, RFC 3761 [2]) is a system that transforms E.164 numbers [3] into domain names and then uses DNS (Domain Name Service, RFC 1034 [4]) services like delegation through NS records and NAPTR records to look up what services are available for a specific domain name. This document registers 'Enumservices' according to the guidelines given in RFC 3761 [2] to be used for provisioning in the services field of a NAPTR [5] resource record to indicate what class of functionality a given end point offers. The registration is defined within the DDDS (Dynamic Delegation Discovery System [6] [7] [5] [8] [9] ) hierarchy, for use with the "E2U" DDDS Application, defined in RFC 3761 [2]. This document registers the ENUMservice "mobileweb" using the URI schemes 'http:' and 'https:' as per the IANA registration process defined in the ENUM specification RFC 3761. The ITU (International Telecommunication Union) collates reports of world mobile usage. The total number of mobile subscribers has reached more than 1.3 billion as of 2003, according to its statistics. As the market of mobile telephony service has kept growing, the number of mobile internet users has been gradually increasing. Mobile ENUM usage will be of high importance according to its convenience and portability; the number of mobile devices with Internet access that can take advantage of its convenience may well outweigh those with fixed connectivity. Mobile devices do have some special characteristics that lead to optimisation of content; they tend to have smaller screens, and at present their access bandwidth is relatively low whilst the latency over this access is relatively high. In particular, a number of schemes have been developed to provide web-based content that is optimised for these characteristics - these schemes can be described as providing "Mobile Webpages". Such Special purpose Mobile Webpages are smaller and simpler than web pages for general use; the Mobile Webpage is designed to fit within the pocket-sized display of mobile terminals, and to reflect the "long pipes" by which these terminals are connected. Mobile web services are being provided using different protocol Ra, et al. Expires January 18, 2006 [Page 4] Internet-Draft Mobileweb Enumservice Registration July 2005 architectures. Currently there are three representative different protocol architectures for the mobile web service : WAP [10], ME [11] and i-mode [12]. This document registers mobile web-service (mobileweb) as an ENUMservice with veriants to reflect these three protocols (WAP, ME and i-mode), together with "uniform" variants that indicate that the content is optimised for mobile use, but uses a standard protocol architecture. Ra, et al. Expires January 18, 2006 [Page 5] Internet-Draft Mobileweb Enumservice Registration July 2005 3. Current Status of Mobile Web Services A Mobile Webpage is a simplified form of general web page, designed to be displayed in the small screen of a Mobile Terminal. Currently, there are three representative protocol architectures used for a mobile terminal to access mobile web-pages. These three protocols are WAP (Wireless Application Protocol)[9], ME (Mobile Explorer)[10] and i-mode[11]. These differ in the method they use for the mobile terminal to request and receive a mobile webpage, and the markup language in which the mobile webpage is presented. The following figures show brief specifications of the WAP, ME and i-mode protocol architectures: WAP Protocol Architecture [WAP 1.x and 2.0] ------------ --------------------------- ------------ | Device | | WAP Gateway | |Web Server | ------------ --------------------------- ------------ | WSP | Encoded | WSP | | | | ------------ WML -------------- HTTP | WML | HTTP | | WTP | Page | WTP | | Page | | ------------ <--------.------------------------- <--- ------------ | WTLS | | WTLS | SSL | | SSL | ------------ --------------------------- ------------ | WDP | | WDP | TCP | | TCP | ------------ --------------------------- ------------ | Bearer | | Bearer | IP | | IP | ------------ --------------------------- ------------ [WAP 2.0 only] ------------ ------------ | Device | |Web Server | ------------ ------------ | WP HTTP | | HTTP | ------------ WML or --------------------------- WML ------------ | TLS | XHTML MP | WAP Proxy | or | TLS | ------------ Page --------------------------- XHTML------------ | WP TCP | <------- | WP TCP | TCP | MP | TCP | ------------ --------------------------- Page ------------ | IP | | IP | IP |<----| IP | ------------ --------------------------- ------------ | Wireless | | Wireless | Wired | | Wired | ------------ --------------------------- ------------ Ra, et al. Expires January 18, 2006 [Page 6] Internet-Draft Mobileweb Enumservice Registration July 2005 Figure 1 ME Protocl Architecture [ME] ------------ ------------ | Device | |Web Server | ------------ ------------ | HTTP | | HTTP | ------------ m-HTML or ---------------------- m-HTML or ------------ | SSL/TLS | WML | G/W | WML | SSL | ------------ Page --------------------- Page ------------ | TCP | <------- | TCP | TCP | <-------- | TCP | ------------ --------------------- ------------ | IP | | IP | IP | | IP | ------------ --------------------- ------------ | Wireless | |Wireless | Wired | | Wired | ------------ --------------------- ------------ Figure 2 i-Mode Protocol Architecture [i-mode] -------- ---------- | Device| |WebServer| -------- ---------------- ---------- | HTTP | | M-PGW | | HTTP | -------- ---------------- c- ---------- | TLS |c-HTML c-HTML | TLS | TLS | HTML| TLS | -------- Page ----------------- Page ---------------- Page---------- | TL |<----| PPM |<----| TL | TCP |<----| TCP | -------- ----------------- --------------- ---------- |CallCtl| |CallCtl|IP(PMAP)| |IP(PMAP)| IP | | IP | -------- ----------------- --------------- ---------- |Wireless| |Wireless|Wired | |Wired | Wired | | Wired | -------- ----------------- -------------- ---------- Figure 3 Without special application support, Mobile webpages are not be displayed properly on other terminals (such as desktops and laptops); Ra, et al. Expires January 18, 2006 [Page 7] Internet-Draft Mobileweb Enumservice Registration July 2005 they are designed for mobile terminals that have such support. Conversely, "general purpose" web pages are often not displayed properly on mobile terminals. If mobile web-services use ENUMServices in accordance with RFC4002 [13] ("IANA Registration for ENUMServices web and ft"), it is very hard for the mobile service provider, terminal and its user to distinguish optimised Mobile Webpages from "general use" webpages. Moreover, there is no way to discriminate the protocol architecture (WAP, ME or i-mode) used by the mobile web-service, and so that needs to be supported by the terminal. Consequently, the ENUMservice registration used by a mobile web- service must be classified according to the protocol architecture that web-service uses; it needs to use another Enumservice from those specified in RFC 4002. Ra, et al. Expires January 18, 2006 [Page 8] Internet-Draft Mobileweb Enumservice Registration July 2005 4. Mobile Web Service Registration 4.1 Introduction The Enumservice variants registered in this section indicate that the resource identified by the associated URI is capable of being a source of information through a mobile webpage. There are two choices of ENUMservices registration of mobile web- services. These are 'Diverse Mobile Web Service Registration' and 'Uniform Mobile Web Service Registration'. The 'Diverse Mobile Web Service Registration' variants use Enumservice Type 'mobileweb' and different Enumservice Subtypes according to the mobile protocol architecture (WAP, ME, i-mode) employed by mobile web-services. So far, for those Enumservices that have both a type and subtype, the type reflected the kind of service provided, and the subtype reflected the URI scheme needed. However, this document specifies the protocol architecture used for the mobile web-service as the subtype because it is impossible to discern among the protocols of mobile web-service through specifying URI scheme as the subtype (for example, ME and i-mode both use the same URI scheme, http(s)). As you can see in section 2.4.2.1 (ENUM Services) of RFC 3761, Enumservice specifications contain the functional specification, the valid protocols, and the URI schemes that may be returned. There is no implicit mapping between the textual string "type" or "subtype" in the grammar for the Enumservice and URI schemes or protocols. Accordingly, it is not wrong to specify the protocol architecture of mobile web-service as the subtype. If there is a mobile web-site, and that mobile web-service is provided using different URIs depending on the protocol architectures used by the mobile web-service, then that mobile web- service provider uses the appropriate 'Diverse Mobile Web Service Registration' variant. On the other hand, the 'Uniform Mobile Web Service Registration' uses Enumservice Type 'mobileweb' but does not use any Enumservice Subtypes. If there is one mobile web-site, and the mobile web- service is provided using a same URI regardless of the protocols of mobile web-service (namely, if mobile web-server is intelligent and able to branch the connection to the proper web-page according to the supported protocol of mobile web-service), then the mobile web- service provider uses the 'Uniform Mobile Web Service Registration' variant Besides, in accordance with the trend that the protocols of mobile web-service are being unified and converged, this document proposes Ra, et al. Expires January 18, 2006 [Page 9] Internet-Draft Mobileweb Enumservice Registration July 2005 that the unified and converged mobile web-service be registered using 'Uniform Mobile Web Service Registration'. 4.2 Diverse Mobile Web Service Registration with 'http:','https:' Enumservice Name: "mobileweb" Enumservice Type: "mobileweb" Enumservice Subtype: "wap", "me", "imode" URI Scheme: 'http:', 'https:' Functional Specification: This Enumservice indicates that the resource identified by the associated URI scheme is capable of being a source of information through a mobile webpage, using the specified mobile protocol architecture. Security Considerations: There are no specific security issues with this 'Enumservice'. However, the general considerations of Section 7 apply. Intended Usage: COMMON Author: JongYun Ra, Sungwoo Shin, Yongwan Ju, Weon Kim, Lawrence Conroy (for author contact detail, see the Authors' Addresses section) Any other information the author deems interesting: None 4.3 Uniform Mobile Web Service Registration with 'http:','https:' Enumservice Name: "mobileweb" Enumservice Type: "mobileweb" Enumservice Subtype: N/A URI Scheme: 'http:', 'https:' Ra, et al. Expires January 18, 2006 [Page 10] Internet-Draft Mobileweb Enumservice Registration July 2005 Functional Specification: This Enumservice indicates that the resource identified by the associated URI scheme is capable of being a source of information through a mobile webpage. Security Considerations: There are no specific security issues with this 'Enumservice'. However, the general considerations of Section 7 apply. Intended Usage: COMMON Author: JongYun Ra, Sungwoo Shin, Yongwan Ju, Weon Kim, Lawrence Conroy (for author contact detail, see the Authors' Addresses section) Ra, et al. Expires January 18, 2006 [Page 11] Internet-Draft Mobileweb Enumservice Registration July 2005 5. Considerations for the 'WAP' registration In 4.2, mobile web-service conforming to WAP protocol is registered with 'http(s)' URI scheme. As you can see in the brief WAP specification above, for WAP 2.0, it is reasonable to use 'http(s)' URI scheme, whilst it might look unreasonable to use 'http(s)' URI scheme for WAP 1.x because WAP 1.x uses WSP/WTP for transport on terminal-side. However, it is noted that the terminal has a function that transforms http(s) requests in the browser (application) level to WSP/WTP forms, and the WAP Gateway has a function that restores the WSP/WTP forms to the original http(s) requests again. Therefore, the fact that a mobile web-service conforming to WAP is registered with 'http(s)' URI scheme doesn't raise any issues. However, if a URI scheme (e.g wap, wsp, wtp, wsl and so on) for WAP is to be devised in the future, mobile web-service conforming to WAP could instead be registered with the new URI scheme. This would require an update to this registration if that ever occurs. Ra, et al. Expires January 18, 2006 [Page 12] Internet-Draft Mobileweb Enumservice Registration July 2005 6. Expected Behaviour Browser (application) for mobile web-services and its user must know what protocol of mobile web-services is supported. Only so, it is possible to register and connect to a web-service properly. After a ENUM resolution of a E.164 associated with mobile web- service, there are three likely results. In case that only URIs registered by 'Diverse Mobile Web Service Registration' are returned as the resolution result, browser(application) or its user selects the URI registered by a proper Enumservice Subtype(wap, me or imode) and tries making connection with the URI. If there are several proper URIs, browser(application) or its user can select a URI, based on the value of Order and Preference field of NAPTR or the own rule. In case that only URIs registered by 'Uniform Mobile Web Service Registration' are returned as the resolution result, browser(application) or its user selects a URI, based on the value of Order and Preference field of NAPTR or the own rule. If the mobile web-server connected is intelligent and has an appropriate branch web-page, browser(application) and its user can be provided with mobile web-service. If the mobile web-server connected is intelligent and has no appropriate branch web-page, browser(application) and its user can not be provided with mobile web-service. If mobile web-service uses only the unified and converged protocol, and browser(application) supports it, browser(application) and its user can be provided with the mobile web-service. If mobile web-service uses only the unified and converged protocol, and browser(application) does not support it, browser(application) and its user can not be provided with the mobile web-service. In case that URIs registered by 'Diverse Mobile Web Service Registration' and URIs registered by 'Uniform Mobile Web Service Registration' are returned simultaneously as the resolution result, browser(application) or its user must select preferentially a URI registered by 'Diverse Mobile Web Service Registration', based on the value of Order and Preference field of NAPTR or the own rule because it gurantees that browser(application) and its user are provided with mobile web-service. If there is no proper URI registered by 'Diverse Mobile Web Service Registration', browser(application) or its user can select a URI registered by 'Uniform Mobile Web Service Registration', based on the value of Order and Preference field of NAPTR or the own rule. If the mobile web-server connected is intelligent and has an appropriate Ra, et al. Expires January 18, 2006 [Page 13] Internet-Draft Mobileweb Enumservice Registration July 2005 branch web-page, browser (application) and its user can be provided with mobile web-service. If the mobile web-server connected is intelligent and has no appropriate branch web-page, browser (application) and its user can not be provided with mobile web- service. If the mobile web-service uses only the unified and converged protocol, and the browser (application) supports it, then the browser (application) and its user can be provided with the mobile web-service. If mobile web-service uses only the unified and converged protocol, and the browser (application) does not support that, then the browser (application) and its user can not be provided with the mobile web-service. Ra, et al. Expires January 18, 2006 [Page 14] Internet-Draft Mobileweb Enumservice Registration July 2005 7. Security Considerations As used by ENUM, DNS is a global, distributed database. Thus any information stored there is visible to anyone anonymously. Although this is not qualitatively different from publication in a telephone directory, it does expose the data subject to having "their" information collected automatically without any indication that this has been done, or by whom. Data harvesting by third parties is often used to generate lists of targets for unrequested information; in short, it is used to address "spam". Anyone who uses a Web-archived mailing list is aware that the volume of "spam" email they receive increases when they post to the mailing list; publication of a telephone number in ENUM is no different and may be used to send "junk faxes" or "junk SMS", for example. Many mailing list users have more than one email address and use "sacrificial" email accounts when they post to these lists to help filter out unrequested emails. This is not so easy with published telephone numbers; the PSTN E.164 [12] number assignment process is much more involved, and usually a single E.164 number (or a fixed range of numbers) is associated with each PSTN access. Thus, providing a "sacrificial" phone number in any publication is not possible. Due to the implications of publishing data on a globally accessible database, as a principle the data subject MUST give explicit informed consent when data is published in ENUM. In addition, the data subject should be made aware that, due to storage of such data during harvesting by third parties, removal of the data from publication will not remove any copies that have been taken; in effect, any publication may be permanent. However, regulations in many regions will require that the data subject can at any time request that the data is removed from publication, and that consent for its publication is explicitly confirmed at regular intervals. The user SHOULD be asked to confirm opening a mobile webpage because it could impose a charge on the user. Using 'http' URI scheme to connect with a mobile webpage is not secure, so the user should apply the same caution when entering personal data as they would do if using a client application started with any other method. Although this is not a feature of ENUM or these Enumservices, the ENUM-using application on the end system may Ra, et al. Expires January 18, 2006 [Page 15] Internet-Draft Mobileweb Enumservice Registration July 2005 appear different from the user's "normal" browser, so the user SHOULD receive an indication of whether their communication is secured. As evaluating a mobile web page can involve execution of embedded (or linked) content that may include executable code, evaluating a mobile web URL involves risks. If automatic evaluation of a mobile web link were to be used, the querying user would be exposed to risks associated with that automatic download and execution of content. Thus, the client MUST ask the querying user for confirmation before evaluating the mobile web URL; the client MUST NOT download and evaluate the mobile web content automatically. An analysis of threats specific to the dependence of ENUM on the DNS, (threats against which are covered in [17]) and the applicability of DNSSEC to these, is provided in RFC 3761. Ra, et al. Expires January 18, 2006 [Page 16] Internet-Draft Mobileweb Enumservice Registration July 2005 8. IANA Considerations This document registers the 'mobileweb' ENUMservice according to specifications and guidelines in RFC 3761 and the definitions in this document. Ra, et al. Expires January 18, 2006 [Page 17] Internet-Draft Mobileweb Enumservice Registration July 2005 9. References 9.1 Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, BCP 14, March 1997. [2] Faltstrom, P. and M. Mealling, "The E.164 to Uniform Resource Identifiers (URI) Dynamic Delegation Discovery System (DDDS) Application (ENUM)", RFC 3761, April 2004. [3] ITU-T, "The International Public Telecommunication Number Plan", Recommendation E.164, May 1997. [4] Mockapetris, P., "DOMAIN NAMES - CONCEPTS AND FACILITIES", RFC 1034, November 1987. [5] Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Three: The Domain Name System (DNS) Database", RFC 3403, October 2002. [6] Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part One: The Comprehensive DDDS", RFC 3401, October 2002. [7] Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Two: The Algorithm", RFC 3402, October 2002. [8] Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Four: The Uniform Resource Identifiers (URI)", RFC 3404, October 2002. [9] Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Five: URI.ARPA Assignment Procedures", RFC 3405, October 2002. [10] WAP Forum, "Wireless Application Protocol". [11] Microsoft, "Mobile Explorer (ME)". [12] NTT Docomo, "i-Mode". [13] Brandner, R., Conroy, L., and R. Stastny, "IANA Registration for Enumservice 'web' and 'ft'", RFC 4002, February 2005. [14] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", RFC 3986, January 2005. [15] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Ra, et al. Expires January 18, 2006 [Page 18] Internet-Draft Mobileweb Enumservice Registration July 2005 Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol - HTTP/1.1", RFC 2616, June 1999. [16] Rescola, E., "HTTP Over TLS", RFC 2818, May 2000. 9.2 Informative References [17] Atkins, D. and R. Austein, "Threat Analysis of the Domain Name System (DNS)", RFC 3833, August 2004. [18] Bradner, S., "IETF Rights in Contributions", BCP 78, RFC 3978, March 2005. [19] Bradner, S., "Intellectual Property Rights in IETF Technology", BCP 79, RFC 3979, March 2005. Authors' Addresses Jongyun Ra National Internet Development Agency of Korea 1321-11, Seocho2-dong, Seocho-gu Seoul Korea Phone: +82-2-2186-4599 Email: rajy@nida.or.kr Sungwoo Shin National Internet Development Agency of Korea 1321-11, Seocho2-dong, Seocho-gu Seoul Korea Phone: +82-2-2186-4546 Email: ssw@nida.or.kr YoungWan Ju National Internet Development Agency of Korea 1321-11, Seocho2-dong, Seocho-gu Seoul Korea Phone: +82-2-2186-4536 Email: ywju@nida.or.kr Ra, et al. Expires January 18, 2006 [Page 19] Internet-Draft Mobileweb Enumservice Registration July 2005 Weon Kim National Internet Development Agency of Korea 1321-11, Seocho2-dong, Seocho-gu Seoul Korea Lawrence Conroy Roke Manor Research Roke Manor Romsey United Kingdom Phone: +44-1794-833666 Email: lwc@roke.co.uk Ra, et al. Expires January 18, 2006 [Page 20] Internet-Draft Mobileweb Enumservice Registration July 2005 Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. 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Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM 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. Copyright Statement Copyright (C) The Internet Society (2005). 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. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Ra, et al. Expires January 18, 2006 [Page 21]