New secure encrypted server and cooling from Captec

Captec, a company specialising in the end-to-end delivery of secure and encrypted computing solutions, has announced two new developments aimed at the defence sector: a Secure Encrypted Server range and a new Direct Liquid Cooling system. These technologies are designed to address the increasing demands for data security and high-performance computing in challenging operational environments and will be presented at DSEI 2025, the company states in a July press release.

The new server line, designated as the Secure Encrypted Server (SES) range, includes the SES-120 and SES-110 models. These servers incorporate Viasat’s DARC-ssd 600 solid-state drives (SSD) and Captec is the only approved provider capable of supporting up to 4 drives in a single drive set of secure platforms, according to a company representative. These drives have been approved for use by NATO, and have also been evaluated by the UK National Cyber Security Centre (NCSC) under its Commercial Product Assurance (CAPS) scheme, a program that assesses and certifies a product’s security capabilities. An SSD stores data electronically on NAND flash memory chips. The data is saved by trapping electrons in a “floating gate” transistor, which can be read as a binary 0 or 1. Because there are no mechanical parts, the drive can access data instantly, a process that is silent and requires less power than older hard disk drives.

The servers were developed to an aggressive timeline in partnership with Viasat for a UK prime, a company representative explained to Calibre Defence via email. Adding that “the computers were put into 19 inch racks within a test facility with the recorded test data removed. The main focus is the ability the Server has to manage secure removable data.”

The Secure Encrypted Server range is intended to protect classified information, including data categorised as official, secret, and top-secret. According to the company, these servers are suitable for both enterprise settings and tactical environments, such as those found in vehicles, aircraft, and ships, where data security is a priority. There is a growing focus on the ability to store and access data in the field to support the ambitions for greater connectivity between units and the movement of targeting data around the battlefield. 

In a connected development, Captec is introducing Direct Liquid Cooling technology for ruggedised systems. This method of cooling involves circulating a specialised liquid, directly over heat-producing components like CPUs and GPUs. This is a departure from traditional air-cooled systems, which rely on fans to move air across heat sinks. The company states that this new cooling approach allows these components to maintain a more consistent operating temperature, which is crucial for high-performance computing and artificial intelligence applications at the edge.

Maintaining a lower temperature prevents “performance throttling,” a mechanism where a processor reduces its clock speed to prevent overheating. By avoiding this, the DLC technology is intended to allow systems to sustain high performance over longer periods. The company also notes that this cooling method can lead to reduced power consumption, which is a consideration in environments where power is a limited resource. 

Calibre comment

There are some applications in defence where existing commercial computing components can be used. However, defence vehicles – regardless of the domain that they operate in – place very different stresses upon computing components. The reasons for this vary by domain with some commonality. Land platforms will place a lot of vibration stress upon a computer, for example, and will struggle to cool the vehicle maintaining the optimal temperature for the computer. All applications will face size constraints, and a finite availability of power will shape many, too. Historically, it was not expected that every platform in a battlespace would carry a large computer. Many would have radios, which did introduce requirements for ruggedised equipment and cooling. Now, however, the trend is for some form of computer to be carried by most platforms, enabling data from sensors and advanced battle management systems to be operated at the furthest edges of the battlefield. This is driving the demand for secure and rugged servers that can perform even in the most extreme environments. 

By Sam Cranny-Evans, published on 12 August, 2025. Credit for the lead image is Captec Group Plc, it shows one of the SES products.