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Expert Interviews

Brian W. Callahan Discusses Defense System Modernization

Headshot of Brian W. Callahan

Brian W. Callahan, an executive with the Tetra Tech Federal IT Group, provides strategic direction in designing and executing solutions for modernizing mission-critical information systems for Department of Defense (DoD) clients. 

Beginning with his experience in data analysis and the related business process challenges of the client, he leads the development of solution strategy, team building, and application of innovative technologies. Brian’s passion is working with clients to design process improvements and apply appropriate technologies that transform their operations and solve their most challenging problems. For more than 20 years, he has successfully managed a wide range of DoD enterprise-level software development and data analytics implementation efforts, delivering measurable and meaningful performance improvements and cost savings.

Prior to his corporate career, Brian served in the U.S. Army 75th Ranger Regiment (1st Battalion) and in the 12th Special Forces Group, Army Reserves. The Ranger motto Sua Sponte (of their own accord) continues to guide his core values, nurturing an environment where technical experts and program managers are empowered to push themselves toward continual improvement for their clients. Brian holds a bachelor’s degree in Business Administration from the University of Michigan and a Master of Science in Environmental Sciences from Johns Hopkins University.


What is defense system modernization and how has it progressed over time?

In fiscal year 2021, the DoD spent roughly $38 billion on information technology (IT) investments. A significant percentage of this amount—around 75 percent—supported operation and maintenance of its vast IT system portfolio. The DoD IT enterprise is largely made up of legacy systems that have been developed for more than 50 years at substantial cost and include a wide range of architectures, platforms, technologies, development languages, and security standards. The result is a disconnected collection of systems that are outdated, inadequate for their current mission requirements, expensive to maintain, difficult to secure, and simply unable to meet current and emerging DoD needs.

System modernization involves the refactoring and replacement of legacy systems with solutions built using modern technologies that are easier to implement, easier to secure and connect, less expensive to maintain, and deliver greatly improved outcomes. Retiring these legacy systems will reduce sustainment costs and free up funds to invest in new capabilities, which is where the real benefits lie. Defense system modernization has been going on for decades, but with the focus on migrating to the cloud, there is an urgent need to reduce the overall number of legacy systems and consolidate duplicative functionality. This is the core goal of application rationalization through system modernization—eliminate unnecessary systems; combine and connect redundant functionality across systems; and migrate core capabilities to modern, scalable, and cloud-based platforms.


What current trends and challenges does the defense sector face in terms of system modernization?

Cloud computing is currently the major driver for system modernization within the defense sector. The DoD Cloud Strategy, released in late 2018, lays out a vision to stand up cloud environments and migrate legacy systems or build new applications in those environments. The goal is to enable the DoD branches to address legacy system issues and take advantage of the cost savings and increased capability, scalability, and flexibility that the cloud offers. Given the size, scope, complexity, and mission-critical nature of defense legacy IT systems, the effort involved in cloud migration is both massive (hundreds of systems) and costly (billions of dollars).

Early DoD cloud migration efforts attempted a simple lift and shift approach to migrating legacy systems to the cloud, which has shown to be wholly inadequate. The result is simply recreating the existing legacy IT stove-piped systems—with all their inherent costs, risks, limitations, and inadequacies—in a cloud environment, achieving the migration goal without any of the intended benefits. Consequently, there is significant interest within DoD program offices to understand both the cloud development platforms that are best suited to support legacy capabilities and the proven, effective migration processes that will ensure migration success.

There also is a realization that the software development life cycle is a strategic component, as it is integrated in some form or fashion into almost any DoD mission—be it business operations, logistics, or warfighting. Agile and DevSecOps represent a real change from traditional software development and deployment approaches. Combined, they significantly advance a development team’s ability to deliver new, secure capabilities to users at the speed of need. They also bring the client and end users into the development life cycle to improve the quality of the software and better tailor new applications to their specific mission requirements.


What do you think are the next developments in defense system modernization?

Successful migration of legacy capabilities to the cloud will generate considerable cost savings, as application rationalization collapses the number of IT systems requiring support and standardizes technologies across a common platform. More importantly, organizations will enjoy the rapid availability of information, tools, and technologies that will enable them to maintain a strategic edge. Savings realized through cloud migration can be used to support the development and cost-effective provisioning of new and emerging technologies that bring DoD organizations new capabilities—analytics, machine learning, artificial intelligence (AI), and robotic and digital process automation—that are the next logical development in defense system modernization.

Cloud platforms with advanced capabilities will enable rapid decision-making, improve allocation of resources, and facilitate force employment across multiple domains. By enabling our defense services and our allies to respond quickly, effectively, and efficiently to a wide variety of unpredictable and everchanging missions, these cloud platforms will add great value within the defense sector.


What role is Tetra Tech playing to help defense clients advance system modernization?

The cloud, particularly migrating their current systems, is the current focus for many of our clients. Our goal is to realize mission success through developing tightly integrated, cloud-based capabilities that rapidly process and analyze usable information for making and communicating high-quality decisions at speed and at scale. We achieve this goal by rapidly developing process-centric applications, adopting Agile and DevSecOps methodologies and tools, and incorporating smart technologies like AI, analytics, and software bots into cloud platforms.

Technology is obviously critical to cloud success; however, human and organizational factors are equally important. These are often overlooked and become significant barriers to change. To mitigate this, we work closely with our clients to help them involve the users early and often in the development process and help shape an environment supportive to change. This collaboration is key to our Small Business Innovation Research Phase I and II contracts where we are identifying and building specific critical system capabilities in no/low code platforms on the cloud. We view this as a technology partnership, which itself is a modern and innovative approach to software development and IT services.

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