Monthly Archives: November 2016

The secrets of cryptography

“Split up into groups of three,” directed Sophia Yakoubov, associate staff in the Secure Resilient Systems and Technology Group at MIT Lincoln Laboratory and instructor of the LLCipher cryptography workshop. “Within each group, the person sitting on the left is Alice, the person on the right is Bob, and the person in the middle is Eve. Alice must write a secret message in a notebook and pass it to Bob. Eve must figure out Alice’s message and intercept everything that Alice and Bob pass to each other. Alice and Bob each have a lock and matching key, however, they cannot exchange their keys. How can Alice pass her secret message to Bob so that Eve is unable to unlock and view the secret, and only Bob can read it?”

The 13 high school students participating in the workshop glanced at one another until one brave student addressed the entire class, starting a flurry of conversation: “Any ideas?”

Thus began one of the many hands-on challenges that students tackled at the LLCipher workshop held in August at the MIT campus in Cambridge, Massachusetts, and MIT Lincoln Laboratory in Lexington, Massachusetts. LLCipher is a one-week program that introduces students to modern cryptography, a theoretical approach to securing data such as Alice’s secret message. The program begins with lessons in abstract algebra and number theory that students use to understand theoretical cryptography during lessons later in the workshop.

“I decided that LLCipher was for me when I researched the course topics,” says student Evan Hughes. “As I made my way down the topic list, I didn’t understand many of the concepts, so I immediately applied to the program.”

Because of student feedback from LLCipher’s inaugural year in 2015, Yakoubov extended each lesson from two to six hours. “Many students said they wanted more time on learning,” says Yakoubov. “Specifically, they wanted to learn more than one cryptography technique and apply those techniques to ‘real-world’ scenarios, rather than just learn theory.” This year, in addition to the El Gamal public key cryptosystem, students learned the RSA public key cryptosystem. RSA is one of the most common methods to secure data and uses slightly different math from El Gamal. Both RSA and El Gamal use modular arithmetic, a type of math in which integers “wrap around” upon reaching a certain value, i.e., the modulus, similar to a clock that uses 12 numbers to represent 24 hours in one day. El Gamal uses a very large prime number as a modulus; RSA uses a very large composite number, i.e., a whole number that can be divided evenly by numbers other than 1 or itself, with a secret factorization.

To reinforce the techniques and allow students to apply the theory, Yakoubov, along with the help of Uri Blumenthal and Jeff Diewald of the Secure Resilient Systems and Technology Group, created an online platform that includes El Gamal- and RSA-based challenges. “With these exercises, we are able to show students examples of flawed cryptography so that they can see how easily it can be broken,” says Yakoubov. “Students can visualize huge numbers and see why concepts like randomization are so important to effective encryption.” The platform is used throughout the course and includes six challenges that bolster teamwork and creativity.

“Learning about public key encryption is fun because it is so complicated and secretive,” says student Garrett Mallinson. “I like creating codes that no one else can break or unlock — this is like what characters do on television shows in just 45 minutes.”

During the final day of the course, students toured several Lincoln Laboratory facilities, such as the anechoic chambers and the Flight Test Facility. “I enjoyed the tour around Lincoln Laboratory,” says Hughes. “We always hear about theoretical concepts at school, so it is inspiring to see people applying and making the things we hear about.”

Solve complex urban problems

MIT has signed an agreement to engage in research collaborations with the Amsterdam Institute for Advanced Metropolitan Solutions (AMS) in the Netherlands. The collaboration’s flagship project, led by researchers from multiple departments at MIT, will be to develop a fleet of autonomous boats for the city’s canals.

Based in Amsterdam, the AMS Institute brings together a consortium of public and private partners to tackle complex urban challenges such as water, energy, waste, food, data, and mobility. MIT joins with two research institutions in the Netherlands — the Delft University of Technology and Wageningen University and Research Center — as the core academic partners who will use the city as a living laboratory and test bed.

An interdisciplinary team from MIT has assembled to lead the collaboration’s first project: ROBOAT, an effort to develop a fleet of autonomous boats, or “roboats,” to investigate how urban waterways can be used to improve the city’s function and quality of life.

The ROBOAT project will develop a logistics platform for people and goods, superimposing a dynamic infrastructure over one the world’s most famous water cities. “This project imagines a fleet of autonomous boats for the transportation of goods and people that can also cooperate to produce temporary floating infrastructure, such as on-demand bridges or stages that can be assembled or disassembled in a matter of hours,” says Carlo Ratti, professor of the practice of urban technologies in the MIT Department of Urban Studies and Planning (DUSP).

In addition to infrastructure and transport, ROBOAT will also deploy environmental sensing to monitor water quality and offer data for assessing and predicting issues related to public health, pollution, and the environment. “Water is the bearer of life. By focusing on the water system of the city, ROBOAT can create opportunities for new environmental sensing methods and climate adaptation. This will help secure the city’s quality of life and lasting functionality,” says Arjan van Timmeren, professor and scientific director at AMS, who also envisions a multitude of possibilities for a network of roboats, from real-time sensing similar to the MIT Underworlds project to retrieving the 12,000 bicycles or cleaning up the floating waste that ends up in the Dutch city’s canals each year.

Joining Ratti from MIT as co-principal investigators are Daniela Rus, professor of electrical engineering and computer science and director of the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL); Andrew Whittle, the Edmund K. Turner Professor in Civil Engineering in the Department of Civil and Environmental Engineering; and Dennis Frenchman, the Class of 1922 Professor of Urban Design and Planning and director of the DesignX program in the MIT School of Architecture and Planning.

At AMS, Van Timmeren and Stephan van Dijk, research program manager, will coordinate the involvement of another 12 groups of researchers from TU Delft and Wageningen UR. Along with the City of Amsterdam, Waternet, the public water utility of Amsterdam and surrounding areas, will participate in the research.

The first prototypes of autonomous boats, or “roboats,” are expected to be tested in Amsterdam in 2017. The project’s initial phase will last for five years.

With nearly one-quarter of the city covered by water, Amsterdam is an ideal place for developing ROBOAT, according to the researchers. The canal system was once the key functional urban infrastructure of the city and today still plays a major role in recreation and tourism. Amsterdam’s waters, including bridges, canals, and the IJ river and its docks, offer plenty of opportunity to help solve current issues with transportation, mobility, and water quality.

Measuring your heartbeat and breath

As many a relationship book can tell you, understanding someone else’s emotions can be a difficult task. Facial expressions aren’t always reliable: A smile can conceal frustration, while a poker face might mask a winning hand.

But what if technology could tell us how someone is really feeling?

Researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) have developed “EQ-Radio,” a device that can detect a person’s emotions using wireless signals.

By measuring subtle changes in breathing and heart rhythms, EQ-Radio is 87 percent accurate at detecting if a person is excited, happy, angry or sad — and can do so without on-body sensors.

MIT professor and project lead Dina Katabi envisions the system being used in entertainment, consumer behavior, and health care. Film studios and ad agencies could test viewers’ reactions in real-time, while smart homes could use information about your mood to adjust the heating or suggest that you get some fresh air.

“Our work shows that wireless signals can capture information about human behavior that is not always visible to the naked eye,” says Katabi, who co-wrote a paper on the topic with PhD students Mingmin Zhao and Fadel Adib. “We believe that our results could pave the way for future technologies that could help monitor and diagnose conditions like depression and anxiety.”

EQ-Radio builds on Katabi’s continued efforts to use wireless technology for measuring human behaviors such as breathing and falling. She says that she will incorporate emotion-detection into her spinoff company Emerald, which makes a device that is aimed at detecting and predicting falls among the elderly.

Using wireless signals reflected off people’s bodies, the device measures heartbeats as accurately as an ECG monitor, with a margin of error of approximately 0.3 percent. It then studies the waveforms within each heartbeat to match a person’s behavior to how they previously acted in one of the four emotion-states.

The team will present the work next month at the Association of Computing Machinery’s International Conference on Mobile Computing and Networking (MobiCom).