Public Safety

Made in the USA: Engage products are used by state and local government agencies and partners to help ensure access to Public Safety networks and dispatch centers for over 30 Years.

Improved availability of emergency services network during natural disasters

Automatically switch to backup packet satellite network upon detection of T1 failure using Engage IP•Tube with Protector and Compression features.

Lower transport costs for routing emergency calls to PSAP

County government reduces T1 backhaul costs for carrying dedicated analog circuits from Local Exchange Carrier to Public Safety Access Point by converting T1 circuits to packets with the Engage IP•Tube and transport traffic over a lower cost packet network.

Increased reliability of state-wide emergency services network

T1 traffic routed over cellular network only when circuit issues exist, maximizing availability while minimizing backup costs.

Increased reliability of nation-wide emergency services networks

Our products provide Public Safety networks and control centers with innovative and cost effective solutions that connect network elements, protect critical circuits and secure network traffic and cryptographic keys. We have a quarter-century of experience developing, manufacturing, and supporting solutions that are critical to our customer’s operations.

Detection of network faults and automatic switchover to backup satelliteor cellular services, and lowering the cost of routing calls to Public Safety Answering Points (PSAPs) are a few of the ways Engage benefits Public Safety networks.


Success Story

Mission Critical: Public Safety Land Mobile Radio over IP

IPTube VF, a Voice Frequency full duplex 4 Wire Analog Circuit to Packet Converter. It is used by State and Local Public Safety organizations to preserve their investment in analog Land Mobile Radio (LMR) infrastructure and field radios, as well as eliminate expensive leased analog backhaul circuits.

LMR systems provide critical mobile and portable real time communications for state and local public safety first responders such as police and firefighters. However, many of these systems use analog field radios and analog wireline leased circuits for tower backhaul.

The IPTube VF is a proven and cost effective alternative for LMR tower backhaul. It digitizes the analog signal, encapsulates it into IP packets, and retains timing information across the link, for seamless replication of the analog signal at the other end. Existing radio, tower and head-end infrastructure and operating procedures are maintained while reducing overall operational costs.

For LMR towers with access to an organization’s intranet (i.e. rooftop of a networked facility), the monthly backhaul costs using the IPTube VF are virtually $0. Other packet services such as DSL, Cable, and 4G/LTE cellular can also be used and in many cases cost less than $50 per month. The Return On Investment of employing the IPTube VF to eliminate leased 4-wire analog circuits is measured in weeks.



Success Story

Public Safety Communications Network Dramatically Increases Network Availability

A major networking company owns and operates a public safety trunked radio system serving statewide public safety agencies. The P25 radio system utilizes T1 trunks for connection between approximately 180 tower sites and three regional centers. State Police, Highway Authority, county and municipal agencies all rely on the public safety radio system for critical public safety communications.

To ensure a high availability of service, the networking company’s engineers focused on minimizing service interruptions caused by T1 outages. In the event of a T1 failure, they wanted the circuit to automatically switch to an alternate path on a different access network. Cellular, with its increasing capacity and reliability, was determined to be a viable solution for this backup path. However, next generation 3G/4G cellular networks are packet based and don’t support native T1 circuit transport. The engineers needed equipment that would convert a T1 signal to IP, and automatically switch to the cellular path when the primary T1 failed.

The Engage Communication IPTube circuit emulation product line was just the solution the engineers were looking for. They had successfully used the IPTube for automatic protection switching of T1 over satellite links, and decided a similar solution would be effective for cellular backup of the critical P25 network. Engage Communication IPTube T1-over-IP solutions encapsulate TDM data into IP packets for transmission over IP & Ethernet connections. The IPTube uses circuit emulation to transparently transport T1 voice and data, enabling interconnection of T1-based PBX/Voice, public safety radio (LMR) and WAN router equipment over packetbased IP links.

The Link Protector option expands IPTube T1-over-IP functionality, adding auto protection switching and eliminating manual intervention in the case of a T1 outage.

Under normal operation, IPTube with Link Protector functions in a PassThru (transparent) mode, continuously monitoring the quality of the primary leased T1 connection. In the event of a T1 outage, the IPTube immediately detects the failed connection, switches from PassThru mode to T1-over-IP mode, and routes customer T1 traffic over an IP link.

In the public safety radio application, IPTube equipment is installed at the radio tower sites and at the regional centers. The primary T1 trunks, linking tower sites back to the regional centers, are monitored for quality on an ongoing basis. If a T1 link drops below customer configured performance levels, the IPTube automatically switches tower traffic over the cellular network, restoring T1 connectivity between the tower and the regional center. See Figure 1.

Fig 1 – Engage IP-Tube provides Auto Backup of T1s over Cellular Network

  •  Under normal conditions, IPTube provides PassThru of Primary T1, monitoring the primary T1 path
  •  Upon T1 outage, IPTube routes T1 traffic over Cellular network, immediately restoring T1 connection  

The IPTube automatically switches back to the primary T1 trunk when service is restored. With the IPTube again in PassThru mode, the public safety radio traffic is returned to the primary T1 trunk. The primary T1 is monitored for future outages, and the cellular connection can be terminated.

IPTube T1 units are available in standalone configurations for deployment at remote tower sites, and in chassis versions for aggregation at regional centers. IPTube circuit emulation solutions from Engage Communication offer a number of specialized features which help to ensure a high quality T1 connection over the cellular network:

  • Lossless Data Compression reduces Ethernet bandwidth by eliminating idle and redundant data, minimizing cellular bandwidth required;
  • Far-End Echo Cancellation suppresses echo in PBX and other Voice applications;
  • Assured Delivery Protocol greatly improves on UDP best-effort transport used in TDM-over-Ethernet products by enabling retransmission of dropped packets as well as packet out-of-sequence correction
  • Transparent TDM over IP mode ensures all customer traffic types can be carried over the emulated T1 circuit;
  • Alternatively, the HDLC-over-IP protocol makes efficient use of cellular bandwidth for WAN router traffic.

The availability of higher capacity/higher reliability cellular networks and IPTube T1 Circuit Emulation makes it possible to significantly improve availability for critical public safety communications networks.

Highlighted Solutions

Improved availability of emergency services network during natural disasters
 Opportunity: State government requires terrestrial T1 circuit backup during natural disasters to maintain emergency services connectivity.

• Solution: Automatically switch to backup packet satellite network upon detection of T1 failure using Engage IP•Tube with Protector and Compression features. 

 Result: When a storm knocks out terrestrial T1 circuits, connectivity is automatically restored via satellite, keeping emergency responder networks functioning.
Lower transport costs for routing emergency calls to PSAP
Increased reliability of state-wide emergency services network

Industry Feedback


“The Department of Defense Service Branches are very good, and very thorough when developing standards, and then evaluating equipment and components to those standards. They do multiple vendor comparisons, and pick the very best. Engage’s IP•Tube GT1 was judged to be the best TDM over IP technology for voice transport in this system, and was therefore included in the spec.”

Tim Carney, Vice President, ACG Systems

“Engage has simply been a great company to work with, they are always dependable and attentive to our program needs, whether it was cost, schedule, or performance.”

Program Manager, Fortune 500 Defense Contractor

Products and Solutions

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Engage Communication
9565 Soquel Drive. Aptos, CA 95003
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Telephone: 1-831-688-1021
Toll Free : 1-877-ENGAGE4
Designed, Fabricated, and Assembled
in America 
Supported Worldwide