E.164 to MetaData (E2MD) (proposed charter) ======================== Last Modified: 2010-03-21 Additional information is available at tools.ietf.org/wg/e2md [not yet in use] Chair(s): * TBA Real-time Applications and Infrastructure Area Director(s): * Robert Sparks * Cullen Jennings Real-time Applications and Infrastructure Area Advisor: * Cullen Jennings Mailing Lists: General Discussion: e2md@ietf.org Listinfo: https://www.ietf.org/mailman/listinfo/e2md To Subscribe: e2md-request@ietf.org In Body: subscribe Archive: http://www.ietf.org/mail-archive/web/e2md/index.html Description of Working Group ---------------------------- Abstract -------- E.164 to MetaData (E2MD) will build on ENUM (E.164 Number to URI Mapping) in either public or private instantiations to provide additional information about E.164 (telephone) numbers. In some use cases, information (metadata) about E.164 numbers cannot be expressed as a URI (Uniform Resource Identifier) as required by the ENUM DDDS (Dynamic Delegation Discovery System) described in RFC 3761bis. Therefore, E2MD will define a different mechanism for mapping E.164 numbers to metadata. The initial expectation is that this mechanism will be a new DDDS application, based on RFC 3761bis. The E2MD DDDS returns metadata either directly as standardized matadata, or indirectly by returning a URI pointing to a resource containing actual metadata. Background ---------- ENUM provides an identifier mapping mechanism to map E.164 (telephone) numbers to Uniform Resource Identifiers (URIs) using the DNS. ENUM is typically used to look up the services associated with an E.164 number, each of which is represented by a URI. However, there is more information about an E.164 number that may be useful when establishing a communications session using that E.164 number. For example, this information might be used to decide what sort of communications session to establish using that E.164 number, or whether to accept a communications session offered by someone using that E.164 number. We refer to this information as "metadata". Several example use cases for metadata have been documented as Internet-Drafts, and will be considered during the work of E2MD for inclusion in the group's work product. Previous Enumservice proposals tried to resolve these issues by using the 'data' URI scheme or inventing completely new URI schemes, however it is believed that such proposals do not satisfy the general use case for metadata, and a new approach is required. Problem Statement ----------------- Typically, the E.164 number associated metadata is such that it cannot be described using a URI consistent with those returned by a lookup using ENUM (RFC 3761bis), making a direct use of RFC 3761bis inappropriate. However, the basic lookup mechanism of RFC 3761bis appears to provide a good foundation for a metadata lookup service, so E2MD will work from this basis. The initially favored approach is to define an additional DDDS application (E2M) that maps E.164 numbers to metadata, which will operate in parallel to the current DDDS application for ENUM (E2U) that maps E.164 numbers to URIs. Current proposals for metadata to be addressed by E2MD include (but are not limited to) 'cnam' to provide information about the calling party name, 'unused' to provide a hint that a number is not in use, 'send-n' to describe the structure of an ENUM tree, 'spid' to describe a communication service provider identifier, 'itad' to describe an internet telephony administrative domain, etc. Scope of Working Group ---------------------- The E2MD Working Group is chartered to develop a new Dynamic Delegation Discovery System (DDDS) application (E2M) that can be used with DNS NAPTR RRs for resolving E.164 numbers into metadata. E2MD will provide the means for data related to E.164 numbers that do not fit into the classic concept of ENUM (E2U). Furthermore, the E2MD working group will produce guidelines for the development and review of future proposals for E2MD service specifications, as well as define a registration process for future E2MD services. A new IANA registry will be specified for registration of E2MD services. The registration policy shall be Expert Review and Specification Required (see RFC 5226), similar to those specified for Enumservice registrations. Until this registration process is in place, the E2MD working group will act as the central point for discussion and review of proposals for new E2MD services. The E2MD working group will ensure that each E2MD service specification published follows IETF practices and, in particular, includes a thorough Security Considerations section as defined in RFC 3552 / BCP 72 "Guidelines for Writing RFC Text on Security Considerations". The E2MD specifications shall reuse as much as possible from the ENUM DDDS application and its IANA registry specification. Limitations of the DNS are to be considered while defining the protocol; in particular packet size restrictions of deployed DNS transport. E2MD shall not be specified as a general purpose lookup nor as bulk transfer protocol, but rather focus on clear use cases related to E.164 numbers. Some of the metadata affected by E2MD standardization may be subject to policy constraints within certain administrative jurisdictions, such as national boundaries. When such policy constraints exist, it is the responsibility of E2MD operators to comply with those constraints on the handling of metadata. The E2MD working group will not attempt to anticipate or mandate such policies. Rather, it is assumed that if policy constraints exist for access to the metadata in an E2MD database, then such policy will be enforced by the E2MD operator. In particular, the E2MD working group will not address AAA issues within the E2MD framework. Goals and Milestones -------------------- Aug 2010 Submit Internet Draft(s) for the E2MD DDDS application and its IANA registry specification to IESG Dec 2010 Submit 'cnam' and 'unused' as E2MD service registrations (Informational) to IESG XXX 2011 Close the E2MD Working Group (or recharter) Internet-Drafts --------------- http://tools.ietf.org/html/draft-hoeneisen-e164-to-metadata-02 http://tools.ietf.org/html/draft-ietf-enum-unused-04 http://tools.ietf.org/html/draft-ietf-enum-cnam-08 (http://tools.ietf.org/html/draft-bellis-enum-send-n-02) Request For Comments -------------------- None