Skip to main content
about c4i header picture


Slider Picture Intel/Joint Forces


Products Header Picture


Press Header Picture


Find out the latest announcements. 

About us

Since 1989, C4i has led advancements in secure communications for the world’s most demanding mission-critical environments. C4i’s interoperable communications solutions are used by defence, governments and industry in more than 40 countries. C4i products enable rapid response times, interoperability and flexible asset utilization, and provide customers with ongoing cyber security protection.

More about us

News & Events

Preview picture for FREQUENTIS C4i and Lockheed Martin unite to strengthen Australian national security

FREQUENTIS C4i and Lockheed Martin unite to strengthen Australian national security

  • As a supplier to Lockheed on the Air6500 Project, C4i will provide its VOICE C2 solution ensuring secure communications across air, land, sea, and space
  • Project for Royal Australian Airforce (RAAF) aims to enhance security, rapid response, and interoperability of the country’s defence systems
  • System will bridge classified and non-classified networks to connect systems, strengthen decision-making, and counter modern threats

AIR6500 is the RAAFs multibillion-dollar plan for an integrated communication network promoting seamless operability and connectivity across sensors, weapons, jets, and warships to protect against threats. Lockheed Martin was selected to lead the project in late August 2023, contracting 10 leading-edge Australian companies to support this mission.

As a supplier to Lockheed, Australian defence company, C4i, a member of the Frequentis Group, will provide its secure VOICE C2 technology. This secure communication system acts as a bridge, linking operators, radios, and telephony across the RAAF's operations. This integration will enhance the RAAF's ability to respond effectively in high-pressure situations.


C4i’s secure VCCS, the VOICE C2 system


Melbourne-based critical communications SME, C4i, has been awarded a nationwide voice communication control system (VCCS) contract. Following a successful initial system delivery on behalf of C4i, this contract will expand on what is already one of the largest systems in Asia Pacific.

C4i’s secure VCCS, the VOICE C2 system, offers unparalleled operational flexibility, allowing operators to control any radio – from anywhere – at any time; with the intuitive graphical user interface providing operational access to both local and remote systems, for quicker response times. 

With several hundred controller working positions, working end-to-end, the C4i VCCS will represent one of the largest Voice Over Internet Protocol (VoIP) systems in Asia Pacific and the world.


Lockheed Martin Australia and C4i Collaborate

Lockheed Martin Australia and C4i Collaborate to Build Secure Communication System for AIR6500

Lockheed Martin Australia has joined forces with C4i, Australian secure communications systems expert, signing a contract as part of a proposal to deliver advanced secure communication capabilities to support the Royal Australian Air Force’s AIR6500 Phase 1 Project (AIR6500-1).

The contract will see the two companies work together to design, test, integrate and authenticate secure voice communication technologies as part of the risk reduction phase in transitioning to Lockheed Martin Australia’s proposal for AIR6500-1 acquisition.

The secure communications systems technologies will focus on homegrown secure voice communication systems that connect into next generation Joint Air Battlement Management C2 networks, while increasing system security, rapid response and interoperability in support of the RAAF’s Integrated Air and Defence Missile (IAMD) mission.


Defence SME C4i Pty Ltd in Melbourne

Australian Member of Parliament, Mr. Josh Burns MP, visits Defence SME C4i Pty Ltd in Melbourne

Australian based company, C4i, welcomed Mr. Josh Burns, Federal MP for Macnamara to its facilities  to showcase first hand C4i’s high-end C4i defence secure communication technology. The products  are all designed, developed and built in Melbourne in the centre of his Federal Electorate.

In 2021 C4i received AU$33.6M of export orders, directly contributing to the local economy, securing over 95 high-end engineering jobs in the defence industry and its associated supply chain in the Melbourne/Victoria area. The Frequentis Group intends to create additional job growth in Melbourne by transferring software and hardware Intellectual Property from Europe to Australia, further developing C4i as a global export hub for Air Defence communication technology.


c4i lab integration

Australian SME C4i Pty Ltd achieves AUD$33.6M defence export orders in 2021

Melbourne-based secure communications company achieves historical export orders 

In 2021 C4i Pty Ltd, a Melbourne-based secure communications system expert, achieved the largest value of export orders in its history, increasing by over 37 per cent in 2021.

C4i delivers high-tech Secure Communication System technology to prime contractors and international end user customers including: the US Air Force and Marine Corps, UK Ministry of Defence, Canadian Department of National Defence, Taiwan Airforce, and the Qatar Ministry of Defense. In the Australian Defence market the C4i secure Voice Communication System (VCS) is being rolled out in the Air Defence segment of the Royal Australian Air Force.  


The business received the prestigious Victorian Export Award for Innovation Excellence during the 2017 Governor of Victoria Export Awards (GOVEA) held in Melbourne.

C4i Receives State of Victoria's Innovation in Export Operations Award

The business received the prestigious Victorian Export Award for Innovation Excellence during the 2017 Governor of Victoria Export Awards (GOVEA) held in Melbourne.

C4i is a global leader in IP and data distribution service based secure voice communications for mission-critical environments. It is used in more than 35 countries by a wide range of industries - including aviation, defence, public safety, utilities and transport. 


SwitchPlusIP Voice Communication System Receives Joint Interoperability Test Command Certification

"The certification comes as a result of extensive testing conducted at JITC's Global Information Test Facility to confirm that the system meets all information assurance and interoperability requirements," said Ed Sayadian, president, Harris Mission Networks.

"SwitchplusIP has already been deployed at many U.S. Department of Defense sites. This certification demonstrates Harris' continued commitment to information security."