How might the blitzkrieg of the future arrive? By air strike? An invading army? In a terrorist's suitcase? Actually it could be coming down the line to a pc close to you. Operation Locked Shields, an international army exercise held final month, was not exactly your standard recreation of troopers. It involves no loud bangs or bullets, no tanks, aircraft or camouflage face-paint. Its troops not often even left their management room, deep inside a excessive safety navy base in Estonia. These folks signify a brand new sort of combatant - the cyber warrior. One group of IT specialists participating in Locked Shields, were detailed to attack nine different groups, located all over Europe. At their terminals in the Nato Co-operative Cyber Defence Centre of Excellence, they cooked up viruses, worms, Trojan Horses and other internet attacks, to hijack and extract knowledge from the computers of their pretend enemies. The idea was to learn helpful classes in the way to forestall such assaults on army and commercial networks. The cyber menace is one which the Western alliance is taking critically. It's no coincidence that Nato established its defence centre in Estonia. In 2007, the country's banking, media and authorities web sites have been bombarded with Distributed Denial of Service (DDOS) attacks over a three week period, in what's since turn out to be often known as Web War I. The culprits are thought to have been pro-Russian hacktivists, angered by the elimination of a Soviet-period statue from the centre of the capital, Tallinn. DDOS attacks are quite simple. Networks of thousands of infected computers, generally known as botnets, concurrently access the goal webpage, which is overwhelmed by the amount of visitors, and so quickly disabled. However, DDOS assaults are a mere blunderbuss by comparison with the newest digital weapons. Today, the concern is that Web War II - if and when it comes - may inflict bodily harm, resulting in large disruption and even loss of life. Richard A Clarke, an adviser on counter-terrorism and cyber-security to presidents Clinton and Bush. Clarke's worries are fuelled by the present tendency to place more of our lives on-line, and indeed, they seem like borne out by experiments carried out in the United States. At the guts of the issue are the interfaces between the digital and bodily worlds known as Scada - or Supervisory Control And Data Acquisition - programs. Today, these computerised controllers have taken over a myriad jobs as soon as performed manually. They do every thing from opening the valves on pipelines to monitoring traffic alerts. Soon, they'll develop into commonplace in the home, controlling smart appliances like central heating. And crucially, they use our on-line world to communicate with their masters, taking commands on what to do next, and reporting any problems back. Hack into these networks, and in principle you will have management of national electricity grids, water supplies, distribution systems for manufacturers or supermarkets, and other critical infrastructure. In 2007, the United States Department of Homeland Security (DHS) demonstrated the potential vulnerability of Scada systems. Using malicious software to feed in the improper commands, they attacked a big diesel generator. Film of the experiment shows the machine shaking violently earlier than black smoke engulfs the display. Although this happened under laboratory circumstances, with the attackers given free rein to do their worst, the concern is that, in the future, a belligerent state, terrorists, and even recreational hackers, would possibly do the identical in the real world. Jenny Mena of the DHS. One purpose why Scada methods may be susceptible to hacking is that engineers, relatively than specialist programmers, are sometimes likely to have designed their software program. They are professional of their discipline, says German safety marketing consultant Ralph Langner, but not in cyber defence. Moreover, essential infrastructure software program can be surprisingly exposed. A energy station, for example, may need less anti-virus protection than the common laptop. And when vulnerabilities are detected, it can be not possible to repair them immediately with a software program patch. Langner points out. "And a energy plant has to run 24-7, with only a yearly power-down for upkeep." So till the power station has its annual stoppage, new software program can't be installed. Langner is well-qualified to comment. In 2010 he, together with two employees, took it upon himself to investigate a mystery pc worm referred to as Stuxnet, that was puzzling the massive anti-virus corporations. What he found took his breath away. Stuxnet appeared to focus on a selected kind of Scada system doing a specific job, and it did little injury to another purposes it infected. It was clever sufficient to search out its manner from laptop to pc, looking out its prey. And, containing over 15,000 lines of laptop code, it exploited no fewer than 4 previously undiscovered software errors in Microsoft Windows. Such errors are extraordinarily rare, suggesting that Stuxnet's creators had been highly skilled and really properly-resourced. It took Langner some six months to probe only a quarter of the virus. But his analysis had already drawn startling results. Stuxnet's target, it turned out, was the system controlling uranium centrifuges at Iran's Natanz nuclear facility. There may be now widespread speculation that the attack was the work of American or Israeli brokers, or both. Whatever the reality, Langner estimates that it delayed Iran's nuclear undertaking by around two years - no lower than any air strike was expected to realize - at a relatively small cost of around $10 million. This success, he says, means cyber weapons are here to remain. Optimists say Stuxnet does a minimum of suggest a scrap of reassurance. Professor Peter Sommer, a world knowledgeable in cyber crime, points out that the amount of research and highly expert programming it concerned would put weapons of this calibre past anyone however a sophisticated nation state. And states, he level out, normally behave rationally, thus ruling out indiscriminate assaults on civilian targets. But even this crumb of consolation is denied by Langner, who argues that, having now infected computer systems worldwide, Stuxnet's code is available to anybody intelligent enough to adapt it, including terrorists. One thing is for certain, he provides: If cyber weapons do turn out to be widespread, their targets will lie mostly in the west, slightly than in nations like Iran, which have relatively little internet dependence. Because of this the previous rules of navy deterrence which favoured highly effective, technologically advanced international locations like the United States do not apply: Responding in type to a cyber attack could be effectively unimaginable. This asymmetry is prone to develop, as developed countries turn into ever extra internet-dependent. To date, the Internet Protocol format permits solely 4.3 billion IP addresses, most of which have now been used. But this 12 months, a brand new version is rolling out, offering an inexhaustible supply of addresses and so permitting exponential growth in connectivity. Expect to see far more machines than folks on-line sooner or later. In the house, fridges will robotically replenish themselves by speaking to meals suppliers; ovens and heating techniques will respond to commands from your smartphone. Cars might even drive themselves, sharing GPS knowledge to find the best routes. For industry, commerce and infrastructure, there will be much more reliance on cyber networks that critics claim are doubtlessly vulnerable to intrusion. In actual fact, it has already develop into a challenge for even delicate installations, not to mention households, to remain offline. Although navy and different critical networks are supposedly remoted from the public internet, attackers can target their contractors and suppliers, who plug into the "air-gapped" system at numerous instances. Somewhere down the food chain, a weak web site or a rogue electronic mail will provide a manner in. In line with Richard Clarke, the mighty American armed forces themselves are not immune, since their command & control, provides, and even some weapons systems, also rely on digital methods. The reply it appears isn't any. A new form of weapon appears to be emerging. And the world may must learn to adapt. The primary episode of the three half documentary sequence Danger in the Download offered by Ed Butler will likely be broadcast on BBC World Service on Tuesday 1 May at 00:06GMT and shall be out there afterwards on i-participant. Facing up to threat of cyberwar. The BBC isn't liable for the content material of exterior websites.