Guidance: Land Open Systems Architecture (LOSA)

Land Open Systems Architecture (LOSA) is the Ministry of Defence’s approach to using open standards, common data models and defined interfaces to support land capability integration. It helps systems exchange information more consistently, reduces bespoke integration effort, and makes it easier to upgrade or replace digital capabilities throughout their service life.

LOSA is supported by a set of core products: the Land Data Model (LDM), Generic Vehicle Architecture (GVA), Generic Soldier Architecture (GSA) and Generic Base Architecture (GBA). The LDM acts as the parent data model from which the GVA and GSA data models are derived. The Generic Architectures provide more specific approaches for vehicles, soldier systems and base infrastructure.

Although LOSA is rooted in the land environment, its principles may support wider defence integration where common data models, open standards and defined interfaces are needed. It gives programmes, suppliers and integrators a consistent way to design digital and data elements so that systems can exchange information with shared meaning, rather than relying on bespoke project-by-project integration.

By promoting common architecture and reusable integration patterns, LOSA helps defence platforms work together more effectively and makes future upgrades easier. It supports interoperability across platforms, soldier systems and base infrastructure, while also helping UK land capabilities align more easily with NATO, allies and industry partners.

You should use LOSA if you are working on systems, services or equipment that need to exchange data or integrate with other MOD, allied or industry systems.