The national infrastructure
The UK's national infrastructure is defined by the Government as: “those facilities, systems, sites and networks necessary for the functioning of the country and the delivery of the essential services upon which daily life in the UK depends”.
The national infrastructure is categorised into nine sectors:
- emergency services
- financial services
There are some cross-sector themes such as technology wherein there may be infrastructure which supports the delivery of essential services across a number of sectors.
Critical national infrastructure
Infrastructure is categorised according to its value or “criticality” and the impact of its loss. This categorisation is done using the Government “Criticality Scale”, which assigns categories for different degrees of severity of impact.
Not everything within a national infrastructure sector is “critical”. Within the sectors there are certain “critical” elements of infrastructure, the loss or compromise of which would have a major detrimental impact on the availability or integrity of essential services, leading to severe economic or social consequences or to loss of life. These “critical” assets make up the nation's critical national infrastructure (CNI) and are referred to individually as “infrastructure assets”. Infrastructure assets may be physical (e.g. sites, installations, pieces of equipment) or logical (e.g. information networks, systems).
The Criticality Scale
The Criticality Scale includes three impact dimensions: impact on delivery of the nation's essential services; economic impact (arising from loss of essential service) and impact on life (arising from loss of essential service).
More details of the Criticality Scale can be found in Cabinet Office's Strategic Framework and Policy Statement.