Ten years ago, Brazil became the first country to hold fully electronic national elections. By October 2008, the South American nation was adding a new chapter to its rich history of electoral innovation by using broadband connections over mobile satellite links to transmit the poll results.
Using a spacecraft orbiting at 36,000km above the equator might not seem the most obvious method for relaying an e-vote from A to B. On closer examination, though, it makes sense.
Electronic voting systems usually consist of two devices: a machine at the voters' end on which each voter presses a button or touches a screen to have their say; and a server at the other to count the results. From a communications engineering perspective, the path that digital voting data must follow to link these two devices is the opposite of that in a TV or radio broadcast, where data flows from a central point (the transmission antenna) to an array of receivers - what's known as a point-to-multipoint configuration. Voter data travels multipoint-to-point, from an array of emitters to a central receiver.
'Ask the Audience' - the lifeline offered in the 'Who Wants to be a Millionaire' television show to poll the audience for the answer - is a good example of a basic e-voting application. In this case, each handheld voting machine produces just one vote, which is instantly transmitted either wirelessly or through a studio cable to a central server.
As the size and the geographical distribution of the group to be polled extends beyond the confines of a TV studio to a local council, county, state or country, so does the complexity of the network used to gather the votes.
Terrestrial telecommunications are usually the preferred way to transmit voting data, usually over fibre-optic networks. In Brazil, this approach works very well when it comes to sending electronic vote results from, say, Sao Paulo or Rio de Janeiro to the capital Brasilia, where the Supreme Electoral Tribunal (TSE) is based.
But how about the hundreds of small villages hidden in the depths of the Amazon rainforest and other rural areas where no electricity grid - let alone any terrestrial communication infrastructure exists?
Voting goes up
'In these remote districts we still need to transmit the results immediately after the polls close,' says Giuseppe Dutra Janino, the TSE's secretary of information technology.
He says the only other alternative, which is what they were doing until they started using satellite communications, was to use a boat to transport the memory cards or diskettes that held the data gathered by the voting machines. The boats would have to navigate rivers and cross swamps to reach the nearest transmission point, a process that would take up to a week to complete.
With a population of over 190 million, Brazil is the world's fourth largest democracy. The country has 130 million registered voters, who are grouped into 400,000 electoral sections distributed across 5,565 municipalities.
'We operate 500,000 electronic ballot boxes,' says Dutra Janino. 'This makes Brazil the organiser of the world's largest computerised elections.' Developed in Brazil by Omnitech, Microbase and Unisys do Brasil, the voting machines made their debut in a trial during the 1996 elections, before being used by every voter in every electoral district in 2000.
Two years later, the TSE made its first attempt at using satcoms to speed up the count in the Amazon region. In what is now seen as Brazil's first-generation satellite voting system, diesel generators were used to power electronic ballot boxes whose voting records were then transmitted using Globalstar satellite phones. As the polls closed, a diskette ejected by each ballot box was inserted into a laptop attached to the satellite phone. The Globalstar device then sent the results to a Regional Electoral Court (TRE).
Although the technology was used again in 2004 and 2006, it became evident that it wasn't robust enough. With a maximum data throughput of just 9.6kbit/s, the system was too slow (it took more than 12 hours to confirm official results) and unreliable, frequently suffering from signal loss.
For the 2008 municipal elections, the TSE decided to use a more powerful, broadband satellite network. A public tender called for 1,200 portable terminals supporting both broadband data and telephone connections.
Most of the boxes (1,000) would be dotted all over the Amazon, a vast, four million sq km region (that's 16 times the surface of the UK) comprising nine states of Brazil's Northern and central west regions.
The winning contract went to Tesacom,South America's largest satellite communications service provider. The company partnered with Addvalue Technologies, a Singapore-based equipment manufacturer that would build the 1,200 terminals.
Unlike the hardware used for previous elections, the chosen Wideye Sabre1 boxes were not satellite phones but portable terminals that interfaced with the BGAN (Broadband Global Area Network) service provided by satellite operator Inmarsat. While BGAN supports up to 492kbit/s of symmetric bandwidth, the Sabre 1 terminals can only upload data at up to 240kbit/s. Still, this meant 25 times more uplink bandwidth for each of the isolated electoral sections.
The 2008 municipal election in Brazil marked the first time that the BGAN system was used in an election, and was the world's largest deployment of the technology.
'One of the biggest hurdles we had to overcome was activating the devices,' says Jos' Sanchez Elia, chief executive officer of Tesacom. 'Never before had so many BGAN terminals been simultaneously activated for any other application.'
Each new BGAN satellite terminal needs to be registered with Inmarsat before it is authorised to use the network. 'We were initially told that a much larger number of bulk activations could be done than what was actually possible,' says Sanchez Elia.
Silvina Graziadio, the company's regional sub-director of marketing and communications, recalls: 'In less than three days we activated 1,200 SIM cards when, on an average day, Inmarsat would activate just 20.'
'We brought down the home location register system that Inmarsat uses to activate new terminals,' adds Sanchez Elia.The activation process was carried out from Tesacom's headquarters in Buenos Aires, Argentina, although the terminals were already in Brazil, having recently arrived from Singapore.
As soon as the activation phase was over, the Brazilian military started a complex logistics operation to transport the boxes to each of the electoral sections where they would be used.
The network was configured so that vote results data would be transmitted as files over an FTP connection from a laptop, this time attached to the Addvalue terminals (placed in an open-air space well clear of trees) to the corresponding TRE. Results collated at each of the 27 TREs (one for each of Brazil's 26 states plus the Federal District) were then transmitted directly to Brasilia.
'We set up the system with traffic-control mechanisms that ensured that only the election results data could be transmitted to the TREs,' says Graziadio. (So no free Internet access or email checking for the electoral officers in charge of beaming up the results.) Users did have access to voice communications, albeit restricted to a certain amount of minutes for each BGAN terminal.
These restrictions helped minimise transmission costs and maximise security, crucial given the value of the information that was being exchanged.
Sanchez Elia says Tesacom had to perform several tests prior to the selection of the system, during which 'all the opposition parties were called in and asked to try to hack our private network'.
The link between the TSE headquarters in Brasilia and Inmarsat's servers was configured as an IPSec virtual private network. Communications between the portable terminals and the satellite (as well as between the satellite and Inmarsat's ground station) were secured through satellite-based encryption.
Inmarsat provides near-global mobile broadband coverage by breaking up the surface of the Earth into a series of circles that are individually targeted by spot beams produced by three dedicated geostationary satellites (called I4).
At the busiest time during the 2008 Brazilian elections, after the polls closed at 5pm and the results transmissions began, a single spot beam from the Inmarsat I-4 F2 satellite was relaying data sent from nearly 500 simultaneously operating BGAN terminals.
Traffic congestion was a real concern. 'It was one of the big question marks before the election,' Graziadio admits. 'Was this single spot beam going to be able to handle such an unprecedented amount of simultaneous BGAN terminals?'
As it turned out, the solitary spot beam handled it very well. By 11pm on election day all the results from the Amazon electoral sections had been officially logged. 'Some journalists asked us why we didn't also do the transmission of the other 398,800 electoral sections,' says Sanchez Elia, 'since the results transmitted by our terminals actually arrived much earlier than those coming from Sao Paulo and the rest of the other large urban areas.'
Total air time billed for the satellite traffic generated by the 1,200 terminals cost just $15,000. 'The TSE was [pleasantly] surprised at how low the operational cost of the system was,' says Sanchez Elia.
On 3 October 2010, Brazilians will go to the polls again to elect a new president. It will be the first major election in the country after the successful implementation of mobile broadband satellite voting technology in the Amazon.
The TSE's secretary of information technology says he is very pleased with the way the BGAN satellite terminals performed in 2008 and that, as a result, they intend to use them again in the 2010 general election. A new public tender is being launched to deploy a similar network, only this time the number of terminals used will rise to around 2,000.
As for the remaining 398,000 or so electoral sections, they will have to stick to fibre.