Get future-ready: Transforming defence’s legacy technology

Now, monolithic, non-interoperable systems that sit outside the wider defence ecosystem are the real legacy technology. And often, it’s these systems originally designed to protect the limited domains of land, sea and air that are operating inefficiently in more volatile, multi-domain environments like cyber and coalition warfare. Faced with adversaries that rapidly adapt and the need to share data with government, industry and international partners, these data silos are now more than just a budgetary drain – they’re a barrier to mission readiness. The challenge is not only connectivity; it is trust: who can access which data, under what conditions, and with what assurance – increasingly across organisational and national boundaries.

When an organisation is focused on managing its legacy systems, it fails to advance its capabilities for the new defence sphere, falling behind allies – and adversaries – and limiting mission readiness, coalition credibility and interoperability in turn.

But for many, transforming to a modern IT environment is a complex and challenging task.

Budgets can be tied to legacy systems, making it difficult to fund modernisation or inspire stakeholders. And with complicated interlinked technology setups, finding the specialist expertise to address and plan an upgrade can be challenging.

These barriers lead many organisations to choose a lift-and-shift cloud migration that simply replicates data in the cloud rather than updating how its architected and managed. While expedient, this approach rarely improves interoperability or resilience, and in defence contexts can introduce additional considerations around sovereignty, accreditation, and sustained authority to operate. In other words, it can shift risk rather than reduce it.

Modernisation isn’t easy. But in the changing world of defence, it’s essential. It’s about evolving capability without increasing operational risk, delivering faster insight, safer collaboration and resilient operations.

When you modernise with Fujitsu, you get the benefit of over 60 years of industry experience working on mission-critical, zero-downtime systems for defence partners like the MOD. We understand the reality of operating within stringent assurance regimes, maintaining zero-downtime services, and evolving complex sovereign and hybrid estates safely. So if you want to make your technology transformation-ready, get in touch – the team is ready to help.