BlackBerry Messenger...

By Christopher Williams, Technology Correspondent

During the Arab revolutions earlier this year, attention focused on Facebook and Twitter, but for the looters and rioters of Tottenham, Enfield and Brixton, the communications tool of choice has apparently been BlackBerry Messenger (BBM). It appears to have acted as their private, encrypted social network over the past two nights’ violence.

RIM’s BlackBerry smartphones are very popular among inner city youths on both sides of the Atlantic. The devices themselves are typically cheaper than Android models and the iPhone, particularly on pay-as-you-go packages. But it is software that central to BlackBerrys’ success in this market.

BBM is an instant messaging application, allowing users to communicate in a similar way to text messaging, but effectively for free, as traffic is exchanged via the internet. According to analysts it is replacing text messaging among young people.

“We’ve seen SMS usage fall among young people and the main driver is BlackBerry,” said Graham Brown of Mobile Youth, in April.

Each user has a unique PIN that allows other BBM users to contact them. BBM PINs are typically shared more readily than phone numbers, which means news can spread through the network more quickly than via text messages.

For authorities aiming to track disturbances via this technology, it presents particular problems compared to public social networks like Facebook and Twitter. While chatter in public can be monitored in real time using fairly simple software – and the Met has such capabilities – BBM conversations are more secure.

Messages are strongly encrypted using an algorithm called Triple-DES, which makes them unintelligible to observers. BBM can be intercepted and deciphered more easily than say, BlackBerry email, however, because all devices share the same cryptographic key.

In the words of Crackberry.com, “although PIN-to-PIN messages are encrypted using Triple-DES, the key used is a global cryptographic 'key' that is common to every BlackBerry device all over the world".

“This means any BlackBerry device can potentially decrypt all PIN-to-PIN messages sent by any other BlackBerry device, if the messages can be intercepted and the destination PIN spoofed.”

Within the British security apparatus, such technically-challenging spy work is carried out by GCHQ in Cheltenham and requires a warrant from the Home Secretary. Whether authorities would consider using such a resource – normally concerned with international terrorism and espionage – to spy on youths looting Foot Locker seem unlikely.

Alternatively, RIM can be legally compelled to hand over decrypted versions of BBM conversations, but it would be too slow a process to be useful while disturbances were ongoing.

Finally, and perhaps most likely, police could go “undercover” on the BBM network, aiming to befriend ringleaders and gather intelligence

At time of writing, evidence for the use of BBM, a legitimate technology, by rioters in London is anecdotal. But given its popularity among the relevant section of society, and that the attention now focused on it seems fair.

Facebook and Twitter have meanwhile played their usual role in major events in Britain, that of forums for breaking news, rumour and instant reaction. While Arab youth used them to spread ideas of openness as well as organise their actions, the mindless destruction and theft in London is orchestrated away from public view. Telegraph