Conformance Testing Overview
Conformance Testing is the testing of a device or system against a standard. The objective in the NG9-1-1 Interoperability Testing Program is to determine if an NG9-1-1 functional element is compliant with the requirements set forth in the NG9-1-1 standards. The scope of a conformance test is limited to a single functional element. For example, an Emergency Services Routing Proxy (ESRP) functional element is tested to determine if it satisfies the requirements found in the NG9-1-1 standards that apply to that functional element.
The testing program is envisioned to eventually cover all NG9-1-1 function elements. The scope of this initial project covers the following functional elements:
- Location Information Server (LIS)
- Border Control Function (BCF)
- Emergency Services Routing Proxy (ESRP)
- Emergency Call Routing Function (ECRF)
- Location Validate Function (LVF)
- Bridge
- Logging Service
- Policy Story (PS)
- Call Handling Functional Element (CHFE)
The conformance tests for this project were divided into two broad categories: “basic” and “advanced”. The distinction is largely subjective. Basic conformance tests are simpler and generally involve a single interface or action.
The diagram below provides a visual representation of how the conformance testing system interacts with the Device Under Test (DUT) in a “basic” test.
In the example on the left, the conformance testing system behaves like Functional Element 1 (FE1) and sends a stimulus message to the DUT, which sends a response. In the example on the right, the conformance testing system behaves like two FEs: FE1 and FE2. FE1 sends the DUT a stimulus message, which the DUT modifies and sends on to FE2. In both cases, the testing system checks that the response is valid and declares a verdict of “pass” or “fail”.
Advanced conformance tests typically involve a more complicated dialog between devices and may involve more than just one or two other FEs. The diagram below depicts how the conformance testing system interacts with the Device Under Test (DUT) in an advanced test.
The conformance testing system behaves like three FEs: FE1, FE2, and FE3. FE1 sends the DUT a stimulus message. The DUT performs some action with FE2, followed by some action with FE3, then returns an answer to FE1. The testing system checks that the interactions of the DUT with FE1, FE2, and FE3 are valid and declares a verdict.
