Giga-hurts radio: Terrorists build Wi-Fi bombs to dodge cops' cellphone jammers
Explosives activated by wireless networking signals discovered amid election
Terrorists have been caught strapping Wi-Fi-activated backup triggers to bombs in Indonesia, police claimed this week.
The explosives were discovered in a raid earlier this month, and included a switching mechanism that enabled them to be detonated using a signal sent via Wi-Fi if the main trigger, which uses a SIM card and waits for a mobile phone message to detonate, was blocked by radio-frequency jammers.
"With that, he can put [the bombs] in some backpacks, and later he would just detonate them from a distance of 1km, for example," said Brigadier-General Dedi Prasetyo at a press conference, according to The Strait Times. Yes, we know Wi-Fi doesn't normally have a range of 1km. We'll get to that in a moment.
Indonesia is on high alert ahead of the release of its presidential election results next week. The polls closed in April, and in the past few days Prabowo Subianto, the main challenger to the current presidency, has held rallies asking for the elections watchdog to look into allegations, made by him, of electoral fraud.
It is expected that incumbent president Joko Widodo will be reelected when the results are announced on May 22, and in the lead-up, the cops have been swooping on suspected terrorists: it's feared extremists will set off explosives during street protests over the poll results.
You JAD, bro?
In one such raid on the island of Java, members of militant group JAD (Jamaah Ansharut Daulah), who are aligned with the Islamic State, were cuffed, and the plod found significant quantities of the same explosive that has been used by the Islamic State in bombs in Paris, Brussels, and Sri Lanka.
One of those arrested, according to police, is a professional bomb-maker who was working on the Wi-Fi trigger mechanism. It is not unheard of for bombs to use Wi-Fi signals – there have been several instances in the Middle East – but it is believed to be the first outside the region.
More details about the bombs were given by Dedi in Jakarta on Thursday. While Indonesian police now routinely used signal jammers at large public gatherings, thanks to a spate of bombs in recent years, they only disrupt cellphone communications, leaving wireless networking frequencies untouched.
Even though Wi-Fi will not travel as far as some cellphone signals, the police said that a careful construction of routers and amplifiers can extend the range as far as one kilometer. Which, while it may be news to people that deal with dead spots in their own house, is alarming to security forces trying to secure large areas full of people.
Dedi also complained it's more difficult to jam Wi-Fi signals than cellular, making these Wi-Fi-activated bombs most undesirable, though the spokesman did not go into more detail.
It may be that the Indonesian cops don't have the equipment to flood all the various wireless networking channels with noise effectively enough to disrupt communications. Standard Wi-Fi uses a healthy number of frequency bands, such as 900MHz, 2.4GHz, 3.6GHz, 4.9GHz, 5GHz, 5.9GHz, and 60GHz.
Perhaps the cops resort to turning off phone masts to block messages getting through, and can't do that with rogue Wi-Fi base stations and repeaters. Perhaps the extended Wi-Fi signals are highly directional, or use non-standard radio frequencies, thus evading the Southeast Asian nation's jammers.
Knowledgeable Reg readers are welcome to chip in. If Wi-Fi-activated bombs become a regular threat, we can imagine folks stepping up their efforts to build and deploy more effective Wi-Fi jammers. ®