E9-1-1 Selective Routing Switch

Document Information
Full name: 

NENA Standard Generic Requirements for an Enhanced 9-1-1 SelectiveRouting Switch

Document type: 


Standard number: 

03-005 v1

Document description: 

This document is intended to define the Generic Feature Requirements of an Enhanced 9-1-1 Selective Routing switch. For legibility, this document describes the Selective routing switch as a single switching element even though the NENA Functional Entity Model describes the Selective Routing function as it fits into the E9-1-1 network as a whole. This allows the developer to create the E9-1-1 function as a centrally located switching entity, or as distributed network elements. It also distinguishes which features and characteristics are fundamental to an Enhanced 9-1-1 system, and which, through either current or anticipated advancement of the industry, are deemed optional or additional features of the 9-1-1 network.

Although traditional methods are described for many of the feature requirements of an Enhanced 9-1-1 Selective Routing switch, the method of how the selective routing switch performs that function is left to the creator of the Selective Routing entity. Therefore, whenever this document describes a selective routing switch as a single switching element, it should be understood that this is to aid in readability and describing the requirements. As the 9-1-1 network evolves and matures, the features and requirements of the selective routing function may ultimately be spread across multiple physical components, and look more like the NENA Functional Entity Model than a single switching element.

It is also understood that the manufacturer of a selective routing switch could either use recognized standards and methodology to perform the functions, or could develop (and document) new methods or interfaces between the router and other network components needed to perform the outlined selective routing features.

This document further defines each characteristic as being either a standard element (i.e., fundamental to most/all selective routing switches) or as an optional or enhanced characteristic (i.e., an additional offering by one or more vendors) to the selective routing switch. This document is forward looking, and as such, many features and capabilities of the 9-1-1 network (necessary for the future) are described, even though they may not be currently deployed throughout the 9-1-1 network at this time.

This document describes the features and/or characteristics generally associated with the typically accepted version of an “Enhanced 9-1-1 Selective Router.” Individual cases, including local policies or regulatory constraints may deem many of these features to be unnecessary to meet 9-1-1 public safety needs, and as such, they may not be offered by the 9-1-1 system service provider. This document is applicable to all types of 9-1-1 calls regardless of the caller’s originating service type (i.e., wireless, land-line, POTS, Centrex, PBX, ISDN, VOIP, etc.). It focuses on the routing and handling of the call based on the fundamental concept that the location of the caller is inferred through the TN (ANI) associated with the call setup. Although there are many different methods to establish the call, the outcome is that the calls can all be discussed in this uniform context throughout the document.

Users, manufacturers, and system designers that implement the use of this document will be able to communicate and provide Enhanced 9-1-1 Selective Routing services and features in a more consistent and uniform manner across all sectors of the 9-1-1 industry. This document can provide a common framework and terminology as to what is required and/or expected in an Enhanced 9-1-1 selective routing switch or network. Furthermore, this document identifies the fundamental characteristics of an Enhanced 9-1-1 network, which in most cases are the requirements for any 9-1-1 system provider when offering services to the Public Safety community.

Use of this NENA document will:

  • Provide a common frame of reference between all parties involved in the development, design, manufacture, installation, discussion, ordering, and use of an Enhanced 9-1-1 system or network.
  • Allow for a more seamless deployment of Enhanced 9-1-1 services to the public safety community and end user, including the interoperability between 9-1-1 systems, and other telecommunications service providers.
  • Allow 9-1-1 system providers to offer customized packages to its users through a common platform that is hardware independent.
Committee Information
Committee Name(s): 

Technical – Network

Committee type: 


Document Dates


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E9-1-1 Selective Routing Switch.pdf 178.98 KB