Optimizing mobile small cell defense networks

ATCA chassis fitted with optimized software and COM Express hardware are leading the charge in next-generation network-centric warfare.

4Entire Aerospace and Defense (A&D) networks, from base stations to the core, are being consolidated into small, ruggedized communications platforms that provide the ability for an entire network to be picked up and moved. Femtocells are now being found on Humvees, ships, and even carried in a soldier’s pack, providing unparalleled communications right where it’s needed most. Compact network cores can fit in 2U and 5U ATCA chassis and can easily be transported. However, these ultra-portable cellular networks require a combination of hardware and optimized software that meets specialized Size, Weight, and Power (SWaP) requirements for next-generation network-centric warfare.

Our military networks have been lacking agility and reliability in comparison to the commercial cellular devices the enemy has at its disposal. Efforts in Iraq and Afghanistan have exposed this gap between proprietary radio communications and commercial cellular networks. Smart phones and cellular networks are allowing an unprecedented level of situational awareness, giving soldiers a significant advantage in the palm of their hand, but cellular networks can be difficult to deploy from a military transport vehicle, such as a Humvee or destroyer, because they tend to be very large, heavy, bulky, and power-hungry. In addition, the network nodes are too cumbersome to be portable, lack the ability to deliver ad-hoc communications, and are not easily customizable to deliver the reliability and security that the military requires.

The military wants to take advantage of proven commercial cellular technology and the associated economies of scale for the next-generation mobile communications systems. However, it cannot simply re-use this technology as is. These portable networks require particular architectures and specific hardware and software elements to meet the specific requirements, such as Size, Weight, and Power (SWaP), of network-centric warfare. This is leading to tremendous changes in how the military implements its wartime communications networks as it moves toward adoption of standards-based cellular technology with 3G today and LTE in the future.

Transitioning from proprietary solutions to COTS hardware

The telecom industry has been steadily moving from proprietary to standards-based designs due to refined standards and the development of a healthy supplier ecosystem. As telecom companies transition from proprietary to standards-based architectures, some are now saving resources and capital by outsourcing critical design and validation tasks. By using Commercial Off-The-Shelf (COTS) hardware as opposed to designing a computing system in-house, Network Equipment Providers (NEPs) are now in a position to avoid hardware design altogether and can focus development efforts on software-based value-add features. NEPs are finding that equipment based on open standards architectures typically costs less to deploy because it makes sound economic sense to design scalable platforms that can be employed across multiple applications (Figure 1).

Figure 1: The cost benefits of using COTS rather than proprietary solutions over the lifetime of a military system are apparent from the time of development.

Open standards-based COTS solutions not only address many issues facing equipment manufacturers, they also meet the needs of military programs. Military and aerospace system designers, who are in the process of replacing proprietary architectures, are seeking COTS technologies that competently accommodate the toughest environmental conditions (such as extreme temperatures) yet are efficient enough to meet application needs for power, performance, and heat dissipation. For example, the military is now looking outside of its engineering ranks to guarantee that its components are rigorously temperature tested. Many COTS technologies were designed to both withstand the rigors of military environments, and offer developers readily available, interoperable hardware that reduces design effort.

Putting the pieces together

Next-generation network-centric warfare requires ultra-portable cellular networks that squeeze the entire system, from base station to the core, into a small, ruggedized platform that can be picked up and moved, or even carried in a soldier’s pack (Figure 2). COTS technologies have made tremendous progress in satisfying the size, ruggedness, and performance requirements for a wide range of Aerospace and Defense (A&D) applications.

Figure 2: COTS technology can be leveraged to support the ultra-portable networks required for communications in network-centric warfare.

When combined, COTS technologies such as AdvancedTCA (ATCA) and COM Express provide a complete, deployment-ready solution with the flexibility for design and software enhancements. Together they support a network of networks in a manner that is standards compliant, providing a high level of interoperability and scalability. Many protocols can be consolidated onto one platform of nearly any size to accommodate a variety of missions, with base stations ranging in size from a big box to several smaller distributed units.

No matter the computing technology, year after year designers try to find ways to increase performance. Successfully integrating a high level of computing power basically comes down to board size, board power consumption, and backplane technology. In all of these areas, ATCA has a significant advantage. ATCA is a bladed platform that easily scales features and performance by adding blades that support new applications or more computing power. With its roots in telecom, ATCA was designed to maximize serviceability and availability, leveraging hot-swappable components and redundancy (for example boards, switches, fans, and power entry modules). In the field, an ATCA chassis is powered by stepping up the military vehicle battery voltage to 48 volts, thus avoiding the 120-volt (AC) supply required by a rackmount server. Yet, to attain the maximum benefits from ATCA equipment, manufacturers have realized it takes a combination of telecom and ATCA expertise to bring all of the elements together — chassis, blades, operating system, middleware, and platform management software — into a cohesive platform.

Boosting performance is especially challenging for designers of small form factor systems who face stringent space and power constraints. It's also difficult to keep up with the design churn associated with implementing new processor generations and increasingly complex design rules. As a result, military system developers are turning to COM Express boards, which remove the processor, chipset, and memory from the rest of the design. For example, for the purpose of reducing size and cost, a leading provider of military mobile telecommunications technology and software development completely revamped its system architecture using COM Express, and now the core network is the size of a shoebox and one-tenth the cost of other available solutions.

Figure 3: Radisys’ CEQM67 combines the next generation quad-core performance the Intel Core i7 processor and the Mobile Intel QM67 Express Chipset with Radisys design expertise to provide breakthrough processing performance on a Type 6 COM Express Revision 2.0 module.

The case for small cells in military applications

Small cells provide unparalleled communications right where it’s needed most without adding extra weight or taking up a lot of space. As opposed to a traditional macrocell on a hilltop or a tall tower, a small cell is a wireless base station that is portable and transmits at very low power. Small cells typically use an IP broadband connection (such as cable, DSL, or fiber) for backhaul and eliminate the need for dual-mode handsets, as virtually any existing wireless handset should work seamlessly with a small cell offered by the carrier.

A wireless equipment manufacturer recently set out to design a flexible LTE network solution that could scale from small to large networks to serve U.S. state and local governments seeking to improve public safety. Increasing capacity had to be as simple as adding processing blades to the chassis and activating additional subscriber licenses, while minimizing SWaP was essential for supporting military or disaster response applications in which the wireless network may need to be transported via van or military Humvee. For customers with existing mobile infrastructure, the solution required the flexibility to make use of legacy equipment. To meet its objectives, the equipment manufacturer developed an Evolved Packet Core (EPC) that is available in different hardware configurations, making it a highly scalable and cost-effective solution. The EPC ships in either a 2- or 14-slot ATCA chassis from Radisys, running the full complement of Trillium LTE protocol software including open interfaces for integrating external network elements.

But is it secure?

Commercial cellular networks have built-in security and integrity protection features. These, however, are being modified for military applications. Existing features that can be customized include:

1.  Air interface ciphering – In commercial networks this is based on the Advanced Encryption Standard (AES) and KASUMI and SNOW 3G algorithms, but can be modified to use any defense-grade encryption approach.

2.  Integrity protection – Mobility and session state information is encrypted and decrypted in the core of the network leveraging commercial-grade algorithms, which may be customized for military requirements.

The ATCA platform enables a robust telecom security gateway that offers world-class security features with multi-gigabit performance to secure the backhaul capabilities — the infrastructure for connecting cell sites to the core network. Furthermore, the COM Express combination of Intel Active Management Technology (Intel AMT) and Trusted Platform Management (TPM) ensures remote access transactions are safe and secure. In addition, since small cells are portable and not left in the same spot for long periods of time, they are less vulnerable. However, many NEPs are also addressing security through protocols. For example, Radisys provides the COTS solutions for mobile infrastructure and the expertise needed to customize the solutions based on SWaP constraints, while NEPs bring the specific insight needed to wrap A&D security features around the standard offering.

Warfighters need more situational awareness on the battlefield and better communications back to the command center. Adoption of commercial standards-defined cellular technology solves the agility, reliability, and cost challenges, but does not deliver an ultra-mobile solution enabling ad-hoc network roll-out and the network of networks concept central to next-generation network-centric warfare. These ultra-portable cellular networks require a combination of hardware and optimized software that meets specialized security and SWaP requirements. Modular, ruggedized computers combined with a customizable carrier board provide COTS-based hardware ideal for ultra-portable warfighter communications applications and are specifically developed to support the extreme conditions in the field. The addition of small cell software solutions provides unparalleled communications right where it’s needed most, without extra weight or bulk.

John Long is a product line manager at Radisys, with a focus on ATCA single board computers and storage.