NENA Standard for Enhanced 9-1-1 (E9-1-1) Default Routing Assignments and Functions
"NENA Recommended Standard for E9-1-1 Default Assignment and Call
Routing Functions” document provides an overview of various database and
network specifications and requirements related to Default Routing of
9-1-1 calls. It is intended to help local authority; database and/or
network administrators select a model in the development of standard
default routing arrangements. It identifies and defines methods used to
assign defaults and route 9-1-1 calls when circumstances prevent normal
selective routing. Each approach is used during a specific set of
circumstances; similarly a specific set of circumstances shall determine
which approach is most appropriate.
While default routing schemes are critical to an E9-1-1
compliant set of database and network design, throughout much of the
9-1-1 community, there is misunderstanding from time to time about the
methods used to route 9-1-1 calls when circumstances prevent typical
routing. This document aims at describing such circumstances and the
method(s) used in such circumstances which shall give the community a
common foundation for discussing default call routing schemes.
It shall be recognized that the rationale for default
management within database and network components and for default call
routing is in an evolution with the advent of new communication
mechanisms generating the end of local rate center number assignment
restriction and the introduction of geographic number portability.
Use of this "NENA E9-1-1 Default Assignment and Call Routing Functions” Standard will:
- foster a common understanding of terms used in the
assessment, determination and deployment of default call routing for
- foster fundamental default management rationale for databases;
- explain default call routing ;
- foster increased communication regarding default call routing selections in the planning of E9-1-1 deployments;
- provide alternatives to switch/network vendors regarding desired operational attributes; and
- foster a common set of standards to complete 9-1-1 calls to designated PSAPs when normal selective routing cannot be invoked.