AT&T FirstNET LMR-LTE Interworking Function

Etherstack Case Study

In 2020, Etherstack were selected by Samsung to supply the 3GPP LMR-IWF (InterWorking Function) to the AT&T FirstNet network, the first nationwide network for first responders to be deployed across the United States.

AT&T will eventually connect over 10,000 public safety agency radio networks to the AT&T FirstNet solution, from single agency small towns to large multiagency state-wide public safety networks.

To make this happen, a standards-based 3GPP LMR-IWF (InterWorking Function) is needed to bridge those thousands of LMR networks from different vendors to the 3GPP MCx solution that provides mission critical services over AT&T FirstNet LTE.

Think of the LMR-IWF as an “on-ramp/off-ramp” for mission critical voice and data traffic on a cellular service to your own LMR network.

Etherstack’s engineering and delivery team have successfully completed lab testing of the LMR-IWF with the end customer, and as announced by AT&T late last year, are now moving to support transition into live network support.

Etherstack’s LMR-IWF supports connections to existing LMR networks using the following interfaces:

• TIA APCO Project 25 ISSI (Inter RF-sub system interface)
• TIA APCO Project 25 CSSI (console sub-system interface)
• TIA APCO Project 25 DFSI (digital fixed station interface)
• Analog 2W/4W and AFSI interfaces via customer premises equipment
• ETSI DMR AIS (open standard DMR interface)
• A range of vendor specific (proprietary) RoIP, digital and other analog interfaces

Etherstack’s LMR-IWF product is a high performance, carrier grade, multiagency solution designed to scale to the largest network of its type in the world.

Whether you are seeking a single agency enterprise solution or a multiagency carrier based solution, reach out to Etherstack to discuss your needs.