33 Section 5 DEFEND 5.0.1. The DEFEND elements of this strategy aim to ensure that UK networks, data and systems in the public, commercial and private spheres are resilient to and protected from cyber attack. It will never be possible to stop every cyber attack, just as it is not possible to stop every crime. However, together with citizens, education providers, academia, businesses and other governments, the UK can build layers of defence that will significantly reduce our exposure to cyber incidents, protect our most precious assets, and allow us all to operate successfully and prosperously in cyberspace. Acting to promote cooperation between states and good cyber security practice is also in the interest of our collective security. 5.0.2. The Government will implement measures to ensure that citizens, businesses, public and private sector organisations and institutions have access to the right information to defend themselves. The National Cyber Security Centre provides a unified source of advice in government for threat intelligence and information assurance, ensuring that we can offer tailored guidance for cyber defence and respond quickly and effectively to major incidents in cyberspace. The Government will work with industry and international partners to define what good cyber security looks like for public and private sectors, for our most important systems and services, and for the economy as a whole. We will build security by default into all new government and critical systems. Law enforcement agencies will collaborate closely with industry and the National Cyber Security Centre to provide dynamic criminal threat intelligence with which industry can better defend itself, and to promote protective security advice and standards. 5.1. ACTIVE CYBER DEFENCE 5.1.1. Active Cyber Defence (ACD) is the principle of implementing security measures to strengthen a network or system to make it more robust against attack. In a commercial context, Active Cyber Defence normally refers to cyber security analysts developing an understanding of the threats to their networks, and then devising and implementing measures to proactively combat, or defend, against those threats. In the context of this strategy, the Government has chosen to apply the same principle on a larger scale: the Government will use its unique expertise, capabilities and influence to bring about a step-change in national cyber security to respond to cyber threats. The ‘network’ we are attempting to defend is the entire UK cyberspace. The activities proposed represent a defensive action plan, drawing on the expertise of NCSC as the National Technical Authority to respond to cyber threats to the UK at a macro level. Objectives 5.1.2. In undertaking ACD, the Government aims to: • make the UK a much harder target for state sponsored actors and cyber criminals by increasing the resilience of UK networks; • defeat the vast majority of highvolume/low-sophistication malware activity on UK networks by blocking malware communications between hackers and their victims; • evolve and increase the scope and scale of Government’s capabilities to disrupt serious state sponsored and cyber criminal threats; • secure our internet and telecommunications traffic from hijacking by malicious actors; National Cyber Security Strategy 2016