After internet connectivity in Egypt was reportedly severed for political reasons, what would it take to blackout network access in Australia?
There are a number of methods that could be used to take down Australia's internet communication.
Of the fibre cables linking Australia to the world, the most significant is the Southern Cross Cable which links the nation, and neighbour New Zealand, to the United States.
If this were to be cut or sabotaged, then most Australians would be cut off from much of the internet. And such a feat is quite possible, according to one source familiar with the layout of the crucial fibre networks, speaking under the condition of anonymity.
"If anything happened to Southern Cross, there would be big problems for Australia," he said. "Sabotaging the cable would need devotion but it would not need to be [physically] severed … to take it out for several days."
The source would not be drawn on how the cable could be deactivated, but it could be as simple as a phone call and "a line on a router configuration file", according to Arbor Networks chief scientist Craig Labovitz.
Flick of a switch
Approaching Australia's internet service providers would be the most efficient way for taking Australia offline. In such an unlikely event, the Federal Government would need to flex regulatory muscle to force providers such as Telstra, Optus, iiNet, TPG and Internode to cease routing traffic.
"If ISPs stop resolving, unless you are operating with a provider that is outside the country [which] ignores the directive or is not asked, everyone would be stuck," The Australian Domain Administrator (auDA) chief executive Chris Disspain said.
Based on the multitude of media reports over the last few days, the Egyptian Government has proved that this method works to devastating effect. The nation's providers deactivated telephone and data services, sending the nation into an effective communications blackout. Vodafone said it had complied as if it hadn't, the government had the power to unplug them with more disruptive effects.
"The internet is people power and makes governments very worried," communications analyst Paul Budde said. "If the top five or six providers were forced to flick the switch, that would blackout Australia."
Budde said such a scenario could be exacerbated under the National Broadband Network, assuming that it reduces the number of redundant links and allows the government to terminate services provided by the network's wholesale operator, NBN Co.
Australia's domain name system servers are another vulnerable point and are critical to maintaining access to Australia's websites.
If the seven Australian-based DNS servers and those spread internationally were taken down at the root level, access to .au domain names would fail, according to auDA's Disspain.
"Qantas.com would work, but not qantas.com.au. It would not resolve," Disspain said. "But [the government] would be better to stop internet service providers from resolving."
And Disspain said he would fiercely protect the DNS servers that are under auDA control. The government would need to jump through difficult regulatory hoops to enforce its powers under the Telecommunications Act, unless auDA could be convinced it was in the national interest. "But that is entering the world of the ridiculous," Disspain said.
Alternatively, a network attack on Australia could damage our internet access capabilities or give the government reason to order a blackout.
Internet providers and auDA maintain that they can defend against attacks such as Distributed Denial of Service (DDoS), in which links are overloaded with junk traffic data, and they have proven to do so in the past.
But large attacks usually cause momentary disruption, and can at least be a pain for networking companies while they last.
Industry has typically been reticent to discuss defence techniques, and even more tight-lipped to mention counter-attacks that are known to be used against large DDoS attacks.
"We can stop DDoS," Disspain said, without alluding to techniques.
Budde said that the government may terminate internet connectivity if Australia came under a serious and sustained attack of a scale as yet unseen.
In the event that Australia is sent back to the digital stone age, tools from the era may be a citizen's salvation.
The humble dial-up modem could be used to connect users to the internet over a fixed line if a connection could be made using an offshore internet provider.
But in the hypothetical scenario that the government asked telecommunications providers to stop broadband services, it could also ask providers to stop all national communications services, including dial-up, Disspain said.
If that occurred, satellite communications could be used by those who possess a device capable of using the networks.
"Satellite links do not conform to national boundaries," Disspain said. "They are physically out of reach, but it is slow and would be crowded."
Tools still remain for those without satellite, fixed or mobile connectivity. Australian-developed "batphones", which do not require mobile or terrestrial connectivity but maintain contact using a mesh network, would allow people to communicate over variable distances.