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SLg Interface

dsTest, Developing Solutions, SLg Interface, Location Serrvices, LCS Testing. MME Testing, GMLC Testing

dsTest supports the 3GPP Evolved Location Protocol (ELP) SLg Diameter interface on both the Mobility Management Entity (MME) client and the  Gateway Mobility Location Center (GMLC) server.  3GPP Location Services (LCS) are specified in 3GPP TS 23.271 and the SLg interface in TS 29.172.

Location based services, such as Emergency Services, rely upon LCS.  LCS are also used to optimize network performance and enhance network self-optimization.  With the SLs and SLh interface applications, you can verify your end-to-end LCS solution.

Initiate Subscriber location requests from the GMLC and verify that the MME authenticates the request, retrieves the appropriate  information from the E-UTRAN and responds with the  correctly formatted location information (current or last known) of the requested subscriber.dsTest, Developing Solutions, LCS, Location Based Services, SLs, SLg, SLh, MME, GMLC, HSS, E-SMLC, Location Services, LCS Testing

From the MME, initiate a subscriber location report, and verify that the GMLC acknowledges the message from the MME, correctly processes the information , transferring the correct information to your external LCS client.

Use the MME and GMLC nodes and the SLg Interface application to test Diameter Routing Agents (DRA), Proxies, Relay Agents, and Redirect Agents.  dsTest provides more tools for Location Services EPC compliance testing.

Comprehensive sets of operational measurements for the SLg Interface, Diameter, and socket level are collected at configurable intervals and stored in a SQLite database on the dsTest server.  Real-time measurements may be retrieved through our dsClient CLI interface or graphed via our dsClient GUI interface.


The SLg Interface application implements the following ELP functions:

  • Provide Subscriber Location, in support of EPC mobile terminating positioning (EPC-MT-LR) procuedures;
  • Subscriber Location Report, in support of EPC mobile originating (EPC-MO-LR) and EPC Network Induced (EPC-NI-LR) procedures.

A complete set of events that can be generated with the SLg interface application can be found here.

The Diameter application ID assigned to the SLg interface application is 16777255, and the vendor identifier is 10415 (3GPP).

Advanced Diameter Testing Features

Enhance your testing with Developing Solutions testing assistance solutions:

  • Insert, delete, or replace AVPs in your messages with our SmartAVP solution.  SmartAVP enables you to define proprietary signaling or to corrupt AVPs to facilitate negative testing.
  • Configure commands to define the series of actions and rates that each subscriber takes.  Advanced profiles can be created using SmartEventsto define a mix of traffic based on probability assignments.   With SmartEvents, you can specify when your SmartAVPs are used.
  • Define a set of message templates against which all messages will be validated with our complete Diameter Dictionary.   Every Diameter message is validated, even under load conditions.

Read more about our SmartEvents feature.
Read more about our Advanced Diameter Testing Features.

Supporting Standards3GPP SLg Diameter Interface, Location Services (LCS)

  • SLg – 3GPP TS 29.172
  • LCS – 3GPP TS 29.271
  • Diameter – RFC 6733
  • SCTP – RFC 4960

General Reference Guides

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