ICE 4: Call Routing Based on LoST Hierarchy
NENA held the Industry Collaboration Event #4 (ICE 4) in Irving, Texas at the AT&T Center for Learning the week of 11/14/2011. The focus of the event was emergency call routing based on the LoST hierarchy. This is the core function required to assure reliable and predictable emergency call routing and location validation regardless of the media type or device being used to place a call. The largest and most complex ICE event ever undertaken, it culminated in a successful multi-vendor testing process, resulting in heightened awareness and recognition of the requirements necessary for interoperable call routing. The twenty-two companies involved evaluated multi-vendor interaction between Emergency Call Routing Functions and also included the following functional entities:
  • Emergency Services Routing Proxies
  • Location Validation Functions
  • Location Information Servers
  • Legacy Network Gateways
  • Call logging and recording
  • NG9-1-1 PSAP CPE
  • SIP User Agents
The testing explored a greater detail of specification called for in the requirements in a variety of different "real world” situations focusing on call routing. Specifically, the following interactions and protocols were evaluated:
  • Recursive and iterative LoST queries 
  • Multi-Hop routing cases involving a combination of a forest guide, state-level ECRF, and regional or local "leaf node" ECRF’s
  • Default routing and error handling at the ECRF and ESRP level
  • LIS based location validation utilizing an LVF in a variety of different scenarios
  • Call logging and recording interaction
The final ICE4 summary report is now available.      VIEW VIDEO OF THE ACTUAL EVENT

More information on ICE:
  • Delaine Arnold– NENA ICE Testing Coordination Manager - 813.960.1698
  • Roger Hixson– NENA Technical Issues Director - 614.442.9110

ICE 4 Participants

  • Jason Horning, BullBerry, Chair
  • Bill Mertka, Motorola, Vice Chair
  • Jim Shepard, 911 Datamaster
  • Larry Reeder,
  • Marc Berryman, Digital Data Technologies Inc.
  • Mike Tedder, Emergent
  • Wolfgang Kampichler, Frequentis
  • Avery Penniston, GeoComm
  • Mark Grady, INdigital
  • Christian Militeau, Intrado
  • Karl-Heinz Wolf, ipcom
  • Matt Clark, microDATA
  • Jerry Eisner, RedSky
  • Thanos DeLiligas, Siemens Enterprise Communications
  • Gilles Ferland, Solacom

ICE4 Planning Committee Charter

The NENA NG9-1-1 Industry Collaboration Events (ICE) Steering Committee has approved commencement of planning for the fourth ICE event. As with previous events, the planning and execution will be the responsibility of a Planning Committee. This document provides guidance to the Planning Committee as they begin their work.


Plan and execute an event that:

  1. Attracts and encourages the widest possible participation of vendors that have products in the focus area.
  2. Allows all participating vendors to test all valid architectures and configurations requested.
  3. Delivers relevant feedback on standards to the appropriate NENA Technical Committees
  4. Allows vendors to better understand the interoperability between their implementations and products developed by other vendors.
  5. Allows for the gathering of relevant results data that will be reported to the NENA Technical Committees, to other SDOs, and, at a high level, to all interested parties, all in formats appropriate to the audience in question.

ICE 4 Focus Areas:

ICE 4 primarily focuses on multi-hop LoST routing hierarchy envsioned in NENA 08-003 and IETF RFC 5582 documentation, using call originations from/replicating Internet based originating services and legacy origination equipment for this ICE 4 test cycle. Envisioned tests will include, but are not limited to:

  • Recursive and Iterative LoST Queries (findService with and without validateLocation set to true)
  • Multi-Hop routing cases involving a combination of US Forest Guide, state-level ECRF/LVF, and regional or local "leaf node" ECRF/LVFs.
  • Default Routing behavior handling (both by an ECRF and an ESRP).
  • Civic address validation (Assuming ECRF/LVF WG documentation is ready by mid-June)

The following areas have been explicitly excluded from ICE-4 testing:

  • LoST data syncronization (i.e. the sharing or replication of authoritative mapping information between one ore more ECRF/LVFs)
  • Security and Authentication protocols or mechanisms
  • Discrepancy Reporting
  • Civic Address Boundary response for LVF query

Other testing plans and elements may be included on vendor or operator request.

Scenarios will be added to the charter as they evolve.

This particular event will focus on elements that impact call routing based on the LoST hierarchy. Functional Elements to be tested include but are not limited to:

  • User Agents (SIP and non-SIP based)
  • LNG
  • ESRP
  • LIS
  • ECRF
  • LVF
  • LPG
  • PSAPs (NG9-1-1 and Legacy via LPG)
  • Recording (passive recording by recording/logging vendors)

Exhibit A - Basic NG9-1-1 Architecture

Planning Committee Participation:

Any vendors of products that are required to support the multi-hop routing processes described within this charter are encouraged to actively participate on the Planning Committee. In addition, vendors of products that provide such capabilities are also encouraged to take an active role in the development of scenarios, bilaterals, network designs, and any database setup necessary to support the event.

At this time, participation on the Planning Committee is limited to vendors of actual equipment, and component solutions. No distributors, end users, or other industry stakeholders will be involved in the planning. If any of these stakeholders have comments they would like provide to the Planning Committee, they may do so by providing their comments to the NENA Industry Collaboration Event (ICE) Testing Coordination Manager, Delaine Arnold, via email at

The diagram in the pdf file illustrates both an iterative and recursive call flow that will be tested at the ICE 4 event. Slight variations of this call flow may also be tested.