As we move closer to intelligent computers, they may begin to follow our every move. In this edition of How Dewsoft Stuff will work, we will look at the parts of such a system and how they allow our data and information to move with us.

Send Out the Bat Signal

In order for a computer program to track its user, researchers had to develop a system that could locate both people and devices. The AT&T researchers came up with the ultrasonic location system. This location tracking system has three basic parts:

* Bats – small ultrasonic transmitters worn by users
* Receivers – ultrasonic signal detectors embedded in ceiling
* Central controller – coordinates the bats and receiver chains

Users within the system will wear a bat, a small device that transmits a 48-bit code to the receivers in the ceiling. Bats also have an imbedded transmitter which allows it to communicate with the central controller using a bidirectional 433-MHz radio link
Bats are 3 inches long (7.5 cm) by 1.4 inches wide (3.5 cm) by .6 inches thick (1.5 cm), or about the size of a pager. These small devices are powered by a single 3.6-volt lithium thionyl chloride battery, which has a lifetime of six months. The devices also contain two buttons, two light-emitting diodes (LEDs) and a piezoelectric speaker, allowing them to be used as ubiquitous input and output devices, and a voltage monitor to check the battery status.

A bat will transmit an ultrasonic signal, which will be detected by receivers located in the ceiling approximately 4 feet (1.2 m) apart in a square grid. There are about 720 of these receivers in the 10,000-square-foot building (929 m2) at the AT&T Labs in Cambridge. An object’s location is found using trilateration, a position-finding technique that measures the objects distance in relation to three reference points.

If a bat needs to be located, the central controller sends the bat’s ID over a radio link to the bat. The bat will detect its ID and send out an ultrasonic pulse. The central controller measures the time it took for that pulse to reach the receiver. Since the speed of sound through air is known, the position of the bat is calculated by measuring the speed at which the ultrasonic pulse reached three other sensors. This system provides a location accuracy of 1.18 inches (3 cm) throughout the Cambridge building.

By finding the position of two or more bats, the system can determine the orientation of a bat. The central controller can also determine which way a person is facing by analyzing the pattern of receivers that detected the ultrasonic signal and the strength of the signal.

In the Zone

With an ultrasonic location system in place, it’s possible for any device fitted with a bat to become yours at the push of a button. Let’s say the user leaves his workstation and enters another room. There’s a phone in this room sitting on an unoccupied desk. That phone is now the user’s phone, and all of the user’s phone calls are immediately redirected to that phone. If there is already someone using that phone, the central controller recognizes that and the person using the phone maintains possession of the phone.

The central controller creates a zone around every person and object within the location system. For example, if several cameras are place in a room for videoconferences, the location system would activate the appropriate camera so that the user could be seen and move freely around the room.

When all the sensors and bats are in place, they are included in a virtual map of the building. The computer uses a spatial monitor to detect if a user’s zone overlaps with the zone of a device. If the zone’s do overlap, then the user can become the temporary owner of the device.

If the ultrasonic location system is working with virtual network computing (VNC) software, there are some additional capabilities. Computer desktops can be created that actually follow their owners anywhere with in the system. Just by approaching any computer display in the building, the bat can enable the VNC desktop to appear on that display. This is handy if you want to leave your computer to show a coworker what you’ve been working on. Your desktop is simply teleported from your computer to your coworker’s computer.

Information Hoppers and Smart Posters

Once these zones are set up, computers on the network will have some interesting capabilities. The system will help us store and retrieve data in an “information hopper.” This is a timeline of information that keeps track of when data is created. The hopper knows who created it, where they were and who they were with.

Think of the hopper as a ubiquitous filing clerk. It will change how we think of our computer filing systems. By using a digital camera that is connected to the network, a user’s photographs are immediately stored in his or her timeline. Tape recorders could also send audio memos to the information hopper.

Two items of information created at the same time will be found at the same place on the timeline. The system knows who the user was with when he created the data, and the various timelines of the users working together. This way another timeline can be created to keep track of particular projects.

Another application that will come out of this ultrasonic location system is the smart poster. A conventional computer interface requires us to click on a button on our computer screen. In this new system, a button can be placed anywhere in your workplace, not just on the computer display. The idea behind smart posters is that a button can be a piece of paper that is printed out and stuck on a wall.

Smart posters will be used to control any device that is plugged into the network. The poster will know where to send a file and a user’s preferences. Smart posters could also be used in advertising new services.To press a button on a smart poster, a user will simply place his or her bat on the smart poster button and click the bat. The system automatically know who is pressing the poster’s button. Posters can be created with several buttons on it.

Ultrasonic location systems will require us to think outside of the box. Traditionally, we have used our one computer at work to store all of our files, and we may back up these files on a network server. This new ubiquitous network will enable all computers in a building to transfer ownership and store all of our files in a central timeline.

    * Distance — On Earth, we are only a fraction of a light second apart, making Earth communication nearly instantaneous over the Internet. As you move farther out into space, however, there is a delay of minutes or hours because light has to travel millions of miles, instead of thousands of miles, between transmitter and receiver.
    * Line of sight obstruction — Anything that blocks the space between the signal transmitter and receiver can interrupt communication.
    * Weight — High-powered antennas that would improve communication with deep space probes are often too heavy to send on a space mission, because the payload must be light and efficiently used.

There’s a good chance that humans will travel to Mars before we see the beginning of a new century. How will we communicate with these distant travelers? Scientists, engineers and programmers are already working to develop an interplanetary Internet that will connect us to probes and human space travelers, and allow more information to be sent back to Earth.

Wiring the Solar System

Take a look at the the 1997 Mars Pathfinder rover mission and you will understand space explorers need an interplanetary Internet for deep space communications. Data from the Pathfinder trickled back at an average rate of about 300 bits per second during its mission. Most likely, your computer can transfer data at least 200 times faster than that. An Internet between Mars and Earth would likely yield a data transfer rate of 11,000 bits per second. That is still much slower than your computer’s transfer rate, but it would be enough to send back more detailed images of the Mars surface. Mars Network researchers think that the transfer rate could eventually go to about 1 Megabyte (8,288,608 bits) per second and allow anyone to take a virtual trip to Mars.
An interplanetary Internet is like the Earth’s Internet on a grand scale and with some improvements. Here are the three basic components of the proposed interplanetary Internet:

    * NASA’s Deep Space Network (DSN).
    * A six-satellite constellation around Mars.
    * A new protocol for transferring data.
The DSN is the international network of antennas used by NASA to track data and control navigation of interplanetary spacecraft. It is designed to allow for continuous radio communication with the spacecraft. However, recent space missions have lost communication with the DSN, including the Mars Climate Orbiter and the Mars Polar Lander missions in 1999. There are three global facilities, in California, Australia and Spain, that make up the DSN. Each facility is equipped with one 111-foot (34-meter) diameter high efficiency antenna, one 111-foot beam waveguide antenna (three in California), one 85-foot (26-meter) antenna, one 230-foot (70-meter) antenna and one 36-foot (11-meter) antenna.

In an interplanetary Internet, the DSN will be the Earth’s gateway or portal to that Internet. In a paper published by the MITRE Corp., a company that is financing the Interplanetary Internet Study, researchers suggest that the DSN’s antennas could be pointed at Mars to connect Earth and Mars for at least 12 hours each day. Satellites orbiting Mars should provide a full-time connection between the two planets. A Martian rover, probe or human colony will provide a Mars portal to the interplanetary Internet.

Under the Mars Network plan, the DSN will interact with a constellation of six microsatellites and one large Marsat satellite placed in low Mars orbit. These six microsats are relay satellites for spacecraft on or near the surface of the planet, and they will allow more data to come back from Mars missions. The Marsat will collect data from each of the smaller satellites and beam it to Earth. It will also keep Earth and distant spacecraft connected continuously and allow for high-bandwidth data and video of the planet, according to Mars Network officials. NASA could launch a microsat as early as 2003, with the six-microsat constellation orbiting Mars by 2009. In 2007, the Marsat is scheduled to be placed in a slightly higher orbit than the constellation. All of these dates are still very tentative.

Programmers are developing an Internet file transfer protocol to transmit the messages and overcome delays and interruptions. This protocol will act as the backbone of the entire system much as the Internet protocol (IP) and transmission control protocol (TCP) operate on Earth. IP and TCP, co-developed in the 1970s by Dr. Vinton Cerf, are the messenger service for our Earth-based Internet. These two protocols break up transmitted messages into packets of small data units and route them to a specified destination.

Cerf is part of the team of scientists who are developing a new protocol to enable reliable file transfer over the long distances between planets and spacecraft. This new space protocol must keep the Internet running even if some packets of data are lost during transmission. It must also block out noise picked up while crossing millions of miles. One idea for the space protocol is called the parcel transfer protocol (PTP), which will store and forward data at the gateway of each planet. The protocol would process an information request sent to a gateway and forward it to a final destination. The gateway would then check, process and forward information back down the path it came.

Astronomical Challenges
An interplanetary Internet will make data move drastically faster between Earth and the probes and other spacecraft that are millions of miles away. Engineers need to overcome several challenges before we plan our virtual journey to Mars through cyberspace. These challenges are:

    * The speed-of-light delay.
    * Satellite maintenance.
    * The possibility of hacker break-ins.

On Earth, two computers connected to the Internet are only a few thousand miles away at the most. Because light travels at 186,000 miles per second, it takes only a few fractions of a second to send a packet of data from one computer to another. In contrast, distances between a station on Earth and one on Mars can be between 38 million miles (56 million km) and 248 million miles (400 million km). At these distances, it can take several minutes or hours for a radio signal to reach a receiving station. An interplanetary Internet will not be able to duplicate the real-time immediacy of the Internet that you use. The store-and-forward method will allow information to be sent in bundles and overcome the concern of data being lost due to delays.

The satellites of the Mars Network will be tens or hundreds of millions of miles from Earth and that means that it will be hard to get up there to fix things when they go wrong. The components of these satellites would have to be much more reliable than those circling Earth.

Hackers pose the biggest threat to an interplanetary Internet. Break-ins and corruption of navigation or communication systems could be disastrous for space missions, and even cause deaths in manned-spacecraft missions. Developers are taking every precaution to design a system that will be able to control access. The protocol selected will have to be impenetrable to hackers, something that has not been possible on Earth. Developers may look at the Secure Sockets Layer (SSL) protocol used for financial transactions as a model for securing the interplanetary Internet.

The interplanetary Internet will possibly wire us to Mars within the decade and to other planets in the decades to follow. It will no longer be necessary to go into space to experience space travel. Instead, space will be brought right to your desktop. With enhancements made to boost data rate transfers, you and I might soon be able to take a a virtual space trip to the mountains of Mars, the rings of Saturn or the giant spot on Jupiter.

The 2000 election will always be remembered for the confusion that developed on election night and the days following. Early on election night, TV networks announced that Gore had won Florida, but then retracted that announcement. Then Florida was awarded to Bush, only for it to be announced later that the state was too close to call. Thousands of ballots were tossed out in South Florida because some voters couldn’t decipher the so-called “butterfly” ballot. Disputes over just a few hundred votes are keeping one of these men from claiming the White House, and legal suits and recounts are under way to decide who our next president will be. Perhaps the most amazing thing about the entire situation is that, in what is arguably the most technologically advanced country in the world, Americans are still voting with paper ballots. Little progress has been made since the American forefathers dropped beans in a jar to cast their votes.

We have the technology today to perform computerized elections. In fact, some companies, universities and unions already use e-voting to elect their officials. In the section of How Dewsoft Stuff Will Work, you’ll learn about how the next time Americans vote for the U.S. president, it might be at the breakfast table, checking off an online ballot on a PC or personal digital assistant.

Point and Click Voting

Photo courtesy Sequoia Pacific Voting Equipment
Some voters are already trying out touch-screen voting computers like this one.
Americans live in a country that is heavily dependent on millions of computers. Obviously, you are aware of the impact of computers, since you are reading this over the Internet, but computers do more than just connect us to the World Wide Web. Almost everyone uses an ATM for a good portion of their bank transactions. Computers installed on gas pumps allow us to pay at the pump. We rely on computers to help us perform many everyday tasks, but there are still things we don’t trust computers to do. And one of those tasks is voting. As the 2000 election plays out, many political pundits and techies argue that electronic voting, or e-voting, will prevent a lot of the problems that have put the presidential election on hold. The advantages of e-voting include:

    * Streamlining the voting process.
    * Preventing ballot errors and confusion.
    * Increasing national voter turnout.

Most voters already use some sort of computerized voting system. Punch cards, like the ones used in the disputed Palm Beach County, Fla., precincts, are tallied by a computerized counting machine that detects the punched holes in a ballot. This form of voting has been used since the 1960s. Optical scanners are used for those voting systems that use paper and pen, to detect pen marks made on a ballot. Optical scan vote counters are not as old as punch card technology, but they seem somewhat archaic compared to other technologies that we use everyday. For many, e-voting is the next logical step for elections.

In the punch card system, if you feed the same 100 ballots through the counting machine seven times, you get seven different vote counts. These inaccuracies are a problem when you are counting millions of ballots, and thousands or hundreds of votes can decide the election outcome. There are two e-voting technologies available that could streamline this process, and make counting ballots as easy as hitting a key on a computer keyboard.

In Brazil and the Netherlands, many voters already use an ATM-like machine to cast their vote. Using these machines, voters gather at their traditional voting precinct and cast their ballots in a kiosk, just like the one they have always used. This kiosk retains the privacy that voters want. Voters carry in a cartridge and place it in the e-voting computer, which displays the candidates on a touch-screen, liquid-crystal display. Unlike paper ballots, these machines display information about each candidate aside from their party affiliation, and might even display the candidate’s photo so that there is less confusion over identity. A voter makes their choice for president by touching the screen. Once the voter makes a selection, a new list of candidates, for the next office on the ballot, appears on the screen. If a voter makes a mistake, such as selecting two candidates for the same office, the computer points out this error and allows the voter to correct it. Once the voter has completed the ballot, the computer allows the voter to review his or her choices before returning the cartridge to an election official.

While it’s been more than a week since polls closed on the 2000 U.S. election, and we are still awaiting the final outcomes in many states, including Florida, Oregon and New Mexico, paperless ballots can be counted instantly when polls close. There is no waiting for overseas or absentee ballots, because they can be counted along with the other e-ballots. Everything is electronic, so in addition to the benefit of timeliness, there is also less concern over human error in the counting process.

Electronic polling places are considered to be a stepping stone toward Internet voting, which would allow people to vote from their home or work computer — or any computer with Internet access. Voters could simply point and click on the candidate they support. This type of voting has the potential to significantly increase voter turnout. In 1998, only 44.9 percent of Americans of voting age took the time to vote. Many non-voters say that the inconvenience of registering or voting is the main reason they did not cast a ballot. With e-voting, you might eventually be able to register online. Online voting eliminates the lines at polling places, and gives us the ultimate anonymous vote. If no one actually sees you vote, there is far less chance that they can know for whom you voted.

Testing E-Voting Technology

Several states were taking a close look at e-voting even before election day 2000 — but the aftermath of this year’s presidential election could sway them toward implementing systems in time for the 2004 vote. You may be one of the few voters who took part in one of the various pilot e-voting programs around the country. The success or failure of these test programs will play a pivotal role in determining the future of e-voting.

Approximately 350 military personnel stationed overseas, or in states far from their home polling precincts, are the first Americans to vote via the Internet. This voting program was run by the U.S. Department of Defense’s Federal Voting Assistance Program (FVAP), and is expected to be a viable replacement for absentee or mail-in votes. These military personnel were given a certificate on a floppy disk, which was inserted in a computer. That information was paired with a similar certificate at their home county, allowing the personnel to log onto the system and vote.

This past election day, Riverside County, Calif., conducted the first paperless voting, and it went off with few hitches. Voters used the touch-screen, ATM-like voting machines at 715 polling locations. The e-voting machines are secure, independent computers that cost about $18,000 each. Voters used a cartridge to record their votes, which were then read by a computer. Proponents of electronic voting say that if the computers in Riverside had been used in Florida, a recount would have been instantaneous, if it were needed at all.

Voters in San Diego and Sacramento counties in California, and in Maricopa County in Arizona had the opportunity to cast ballots in an online voting trial on election day. In this so-called “shadow vote,” voters first voted using traditional methods, and then were given the choice to vote again on a computer. The second vote was not counted toward the election, but the online votes will be studied to see if this method has potential for future elections. Tabulation of the hundreds of online shadow votes took only a a few seconds, while tabulation of traditional votes takes hours or days.

With problems continuing to plague the Florida ballot count, it’s likely that officials will give these pilot electronic voting programs some serious consideration. However, e-voting must overcome several obstacles before it becomes widely accepted for use in national elections. In the next section, we will look at some of the legal and technological challenges facing the implementation of e-voting.

Bridging the Digital Divide

Electronic voting is the first new election technology to be introduced in years. Of course, this change doesn’t come without criticism. Traditionally, people are resistant to change, even if it offers an opportunity to simplifying their lives. And to be fair, e-voting does have its drawbacks. Here are just a few:

    * Computers will disenfranchise the computer illiterate, including the elderly, the poor and minorities.
    * It will be very difficult to verify voters’ identities.
    * Computers are susceptible to attacks by computer viruses and hackers.

The digital divide is a rather new term, referring to the gap between the technology haves and have-nots. Those with computer knowledge are typically younger and more affluent than those who lack computer skills. The electronic voting system used in Riverside County has already drawn protests from minority groups who say that this computerized system intimidates voters who have limited access to computers. Studies show that whites and Asians are more computer savvy than blacks and Latinos, that younger voters have more computer knowledge than older voters and that those with money have more access to the Internet than those without money.

The Voting Rights Act of 1965 poses the biggest legal barrier to e-voting. This act called for an end to discrimination against minorities in the election process, and prohibits some states from making changes to voting procedures without federal approval. The courts could declare computer-based or Internet voting a violation of this act.

Another potential problem facing electronic or online voting will be verifying the actual identity of the person casting the ballot. Giving a 10-digit PIN number to voters is one method of deterring voter fraud; fingerprint, iris and retinal scanners could also verify that you are who you say you are when you vote. This would be a significant improvement over the identification process used at polling places now. On election day this year, all that most of us had to do to verify our identities was recite our address. We didn’t have to show any form of identification or proof of who we are.

Many people worry that voting on a computer network may make their votes vulnerable to attacks by hackers. Security measures developed to protect other areas of the Internet, including shopping, have not been able to completely lock out malicious attacks. You’ve probably heard of cases in which someone’s credit card number was stolen online, costing the credit card holder hundreds, if not thousands, of dollars. So how can we be sure that our votes are secure? Security may be the weak link of online voting. Before e-voting becomes commonplace, developers will need to address the prospect of hackers jamming an e-voting computer system and preventing selected groups of voters from casting ballots.

E-voting has its share of flaws, but it might draw more interest following the problems that have plagued this year’s election. In a country that relies so much on technology, we might finally see that technology easing the political process in the next presidential election. Who knows? In November 2004, you could wake up on election day and cast your ballot at a virtual polling booth in the privacy of your own home.