2.5.4 Emergency Context Resolution with Internet Technologies (ecrit)

NOTE: This charter is a snapshot of the 76th IETF Meeting in Hiroshima, Japan. It may now be out-of-date.

Last Modified: 2009-09-30


Hannes Tschofenig <Hannes.Tschofenig@gmx.net>
Marc Linsner <marc.linsner@cisco.com>

Real-time Applications and Infrastructure Area Director(s):

Robert Sparks <rjsparks@nostrum.com>
Cullen Jennings <fluffy@cisco.com>

* The Real-time Applications and Infrastructure Area Directors were seated during the IETF 65.

Real-time Applications and Infrastructure Area Advisor:

Cullen Jennings <fluffy@cisco.com>


Roger Marshall <rmarshall@telecomsys.com>

Mailing Lists:

General Discussion: ecrit@ietf.org
To Subscribe: https://www.ietf.org/mailman//listinfo/ecrit
Archive: http://www.ietf.org/mail-archive/web/ecrit/current/maillist.html

Description of Working Group:

In a number of areas, the public switched telephone network (PSTN) has
been configured to recognize an explicitly specified number (commonly
one that is short and easily memorized) as a call for emergency
services.  These numbers (e.g. 911, 112) relate to an emergency
service context and depend on a broad, regional configuration of
service contact methods and a geographically-constrained context of
service delivery.  These calls are intended to be delivered to special
call centers equipped to manage emergency response. Successful
delivery of an emergency service call within those systems requires
both an association of the physical location of the originator with an
appropriate emergency service center and call routing to deliver the
call to the center.

Calls placed using Internet technologies do not use the same systems
to achieve those goals, and the common use of overlay networks and
tunnels (either as VPNs or for mobility) makes meeting them more
challenging.  There are, however, Internet technologies available to
describe location and to manage call routing.  This working group will
describe when these may be appropriate and how they may be used.
Explicitly outside the scope of this group is the question of
pre-emption or prioritization of emergency services traffic. This
group is considering emergency services calls which might be made by
any user of the Internet, as opposed to government or military
services that may impose very different authentication and routing

The group will show how the availability of location data and call
routing information at different steps in session setup would enable
communication between a user and a relevant emergency response
center. Though the term "call routing" is used in this document, it
should be understood that some of the mechanisms which will be
described might be used to enable other types of media streams. Video
and text messaging, for example, might be used to request emergency

While this group anticipates a close working relationship with groups
such as NENA and ETSI EMTEL, any solution presented must be useful
regardless of jurisdiction, and it must be possible to use without a
single, central authority.  Further, it must be possible for multiple
delegations within a jurisdiction to be handled independently, as call
routing for specific emergency types may be independent.

This working group cares about privacy and security concerns, and will
address them within its documents.

Goals and Milestones:

Done  Informational RFC containing terminology definitions and the requirements
Done  An Informational document describing the threats and security considerations
Done  A Standards Track RFC describing how to identify a session set-up request is to an emergency response center
Done  A Standards Track RFC describing how to route an emergency call based on location information
Done  An Informational document describing the Mapping Protocol Architecture
Done  Submit 'Location Hiding: Problem Statement and Requirements' to the IESG for consideration as an Informational RFC.
Done  Submit 'Framework for Emergency Calling using Internet Multimedia' to the IESG for consideration as an Informational RFC.
Done  Submit 'Best Current Practice for Communications Services in support of Emergency Calling' to the IESG for consideration as a BCP document
Oct 2009  Submit 'Synchronizing Location-to-Service Translation (LoST) Protocol based Service Boundaries and Mapping Elements' to the IESG for consideration as an Experimental RFC
Dec 2009  Submit "LoST Extension for returning Boundary Information for Services" to the IESG for consideration as an Experimental RFC
Mar 2010  Submit "Using Imprecise Location for Emergency Call Routing" to the IESG for consideration as an Informational RFC


  • draft-ietf-ecrit-phonebcp-14.txt
  • draft-ietf-ecrit-framework-10.txt
  • draft-ietf-ecrit-location-hiding-req-02.txt
  • draft-ietf-ecrit-specifying-holes-01.txt
  • draft-ietf-ecrit-lost-sync-08.txt
  • draft-ietf-ecrit-lost-servicelistboundary-01.txt
  • draft-ietf-ecrit-rough-loc-01.txt

    Request For Comments:

    RFC5012 I Requirements for Emergency Context Resolution with Internet Technologies
    RFC5031 PS A Uniform Resource Name (URN) for Emergency and Other Well-Known Services
    RFC5069 I Security Threats and Requirements for Emergency Call Marking and Mapping
    RFC5222 PS LoST: A Location-to-Service Translation Protocol
    RFC5223 PS Discovering Location-to-Service Translation (LoST) Servers Using the Dynamic Host Configuration Protocol (DHCP)
    RFC5582 I Location-to-URL Mapping Architecture and Framework

    Meeting Minutes


    Lost Update
    LoST Sync
    SoS URI Parameter
    ECRIT Direct Calling
    Unauthenticated Access
    Data Only Emergency Messaging