---
title: "Testing Locally-Created Services"
slug: "testing-locally-created-services-lx"
tags: ["test", "SAT test", "Y.1564", "RFC-2544", "Assurance Sensors", "Assurance Sensor GT", "Assurance Sensor GT-S", "Assurance Sensor LT-S", "Assurance Sensor LX-S"]
updated: 2026-07-07T13:56:17Z
published: 2026-01-27T18:07:50Z
canonical: "docs.crossworkassurance.cisco.com/testing-locally-created-services-lx"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crossworkassurance.cisco.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Test Locally-Created Services

You can include services that have been locally created on the unit in a Y.1564 and RFC-2544 test by enabling an internal loopback on of the unit's UNI ports to redirect the test traffic through traffic policies.

Enabling an internal loopback on both UNI ports (near-end and far-end) lets you test services end-to-end, as shown in the following illustration:

## UNI-to-UNI (End-to-End) Testing

![image.png](https://cdn.document360.io/01d1de5e-a375-4fbc-aa82-666ac04c2113/Images/Documentation/image-3N2MMFUA.png?sv=2026-02-06&spr=https&st=2026-11-12T14%3A47%3A22Z&se=2026-11-12T15%3A47%3A22Z&sr=c&sp=r&sig=PSLrqMFJApwh5ScNre8zNFwtANU%2F4YYtsFUP03N3BuQ%3D)

The traffic in this end-to-end test moves seamlessly between the two units:

- The test traffic is generated toward the local UNI port on Unit 1.
- The internal loopback on Unit 1 redirects the traffic to the policies stage, then toward the NNI port.
- The test traffic enters Unit 2 and goes through the policies before reaching the UNI port.
- Another internal loopback is used on Unit 2's UNI port to loop the traffic and send it back to Unit 1.
- In both units, the traffic goes to the policing stages for the ingress direction as well as for the egress direction.

The units can also be configured to perform UNI-to-NNI testing, as well as NNI-to-UNI testing, as shown in following illustrations:

## UNI-to-NNI Testing

![image.png](https://cdn.document360.io/01d1de5e-a375-4fbc-aa82-666ac04c2113/Images/Documentation/image-A8MI8YTC.png?sv=2026-02-06&spr=https&st=2026-11-12T14%3A47%3A22Z&se=2026-11-12T15%3A47%3A22Z&sr=c&sp=r&sig=PSLrqMFJApwh5ScNre8zNFwtANU%2F4YYtsFUP03N3BuQ%3D)

## NNI-to-UNI Testing

![image.png](https://cdn.document360.io/01d1de5e-a375-4fbc-aa82-666ac04c2113/Images/Documentation/image-U1H6EH0N.png?sv=2026-02-06&spr=https&st=2026-11-12T14%3A47%3A22Z&se=2026-11-12T15%3A47%3A22Z&sr=c&sp=r&sig=PSLrqMFJApwh5ScNre8zNFwtANU%2F4YYtsFUP03N3BuQ%3D)

**Notes:** The Internal Loopback functionality only supports Layer-2 and Layer-2 Accedian test frames in conjunction with two-way tests. Other types of test traffic, such as Layer-2 Generic, Layer-3, are not supported. When using an internal loopback, the maximum throughput is limited to 50% of the line rate.

To enable an internal loopback, access the **Port Configuration** menu. For details, see *Setting Up Ports*.

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