In this week’s UMBC ebiquity meeting (10am Tue may 6 in ITE 325), PhD student Wenjia Li will talk about his research on security and MANETs. Guests are always welcome — just drop in. Here’s the title and abstract.
Gossip-Based Outlier Detection for Mobile Ad Hoc Networks
Wenjia Li, University of Maryland, Baltimore County
It is well understood that Mobile Ad Hoc Networks (MANETs) are extremely susceptible to a variety of attacks. Many security schemes have been proposed that depend on identifying nodes that are exhibiting malicious behavior such as packet dropping, packet modification, and packet misrouting. We argue that in general, this problem can be viewed as an instance of detecting nodes whose behavior is an outlier when compared to others. In this work, we propose a gossip-based outlier detection algorithm for MANETs. The algorithm leads to a common outlier view amongst distributed nodes with a limited communication overhead. Simulation results demonstrate that the proposed algorithm is efficient and accurate.
Remember when finding information on the Web was done by navigation using Gopher or Yahoo’s directory? I worked and we thought it was pretty good, at least until the search engines came along. Then we realized that search was much better than navigation for most tasks, especially as the size of the Web grew.
Recall how we get information from a big organization by phone today — we call customer service and navigate a confusing phone menu over the phone and after 10 minutes, end up being told to dial a different department. Dealing with such IVR (Interactive voice response) systems is part of the cost of living in our modern society. But maybe w can do better…
Fonolo offers a service that uses a search engine on their site to find the right spot on a company’s phone menu and connect you to it by a callback to your phone. You can even bookmark the point on the phone menu.
“And Fonolo wrote a web spider that visits large companies’ public phone numbers, and iterates through all the options on all the IVR menus from all the numbers, logging everything it finds. Then it’s just a matter of plotting it all on a directed graph, and making the whole thing searchable and available on the Web. And then the bit we like. You click on the bit you want to get through to, and their system uses the map to dial and navigate the IVRs for you, thus “deep dialing” the user directly to the point in the IVR they need. Every time someone dials through Fonolo, they use the interaction to re-validate that path through the IVR. The search terms that users submit tell them which companies they need to go spider.”
Fonolo is in a private beta mode, but you can sign up to be added to it on thei web site. You can see a video presentation of the idea and some ppt slides
I was very impressed with the ASUS eee PC, which is a well designed and engineered product that delivers a lot at a modest cost. Forbes has a story, :Eee! A New Cellphone!, on ASUS’s plans to manufacture mobile smart phones. In fact, their latest phone, the P527, is already available for sale in the US (e.g., $590 at Amazon, unlocked).
“ASUS says the P527 has a raft of features, including a touch screen, wi-fi, a camera, Windows Mobile software and a number of practical-minded applications. To distinguish it from competitors like the Samsung BlackJack or Motorola (nyse: MOT - news - people ) Q, ASUS loaded the phone with GPS, an FM radio, a business-card scanning program and a “travel log” feature that lets users record their travels and peg photos to specific locations using Google Earth. Even more unique: a feature that acts as a remote control for PowerPoint presentations (via Bluetooth) and an “S.O.S.” service that can track a user’s location and send it, along with a text message, to up to five numbers. “We’re trying to get a unique edge by thinking what users would want on the road and how they could carry less gadgets,” says Huang.”
Reviews, such as this CNet review, are mixed with many complaining about the phone’s slowness.
Language models are widely used in processing both written and spoken language. They are used for part of speech tagging, sense tagging, disambiguation, text similarity metrics, and many other tasks, including predicting the words a person intends when typing on a telephone keypad. The last application has some interesting wrinkles, as this video we spotted on Language Log explains.
The most popular predictive text system in use today is T9, developed by Nuance Communications. You can check out the video’s examples using this T9 demo.
Technology Review has an interesting article on femtocells, which may be the next big thing in home networking and mobile computing.
“Similar in concept to the Wi-Fi routers that many people use to blanket their homes with wireless Internet access, these little boxes instead provide a network for carrying the voice and high-speed data services of mobile phones. They’re designed to give bandwidth-hungry cell-phone subscribers the strongest possible connections at home.” (link)
The idea is attractive and I’d buy one in a minute. I live in a hilly area where the hills do a good job of blocking all kinds of signals — cell phone, TV, and radio. So my mobile phone is almost useless at home, even though I’m in the middle of the Baltimore-DC metropolis.
Femtocell technology has its own industrial organization, the femtoforum, a “a not-for-profit membership organization founded in 2007 to promote femtocell deployment worldwide.”
Here’s a part of the TR article that excites me:
“Today, the equipment cost for femtocells runs in the range of $250 to $300. Sprint, one of the first companies to start commercial trials of the products, is offering them to consumers in Denver and Indianapolis for $50 apiece, along with an offer of lower-priced calling plans–altogether a substantial subsidy.”
Sprint’s press release descibes it’s AIRAVE femtocell, made by Samsung, and their pricing plan: $50 for the femtocell plus $15/$30 a month for the service (individual/family). While at home you talk for free.
Next Friday, UMBC alumnus Filip Perich (PhD 2004) will talk about his recent work using policies expressed in the Semantic Web language OWL to control how software radios manage access to the radio spectrum.
We present an overview of the policy-controlled dynamic spectrum access technology, which provides an order-of-magnitude improvement to wireless communications and spectrum management in terms of spectrum access, capacity, planning requirements, ease of use, reliability, and jam resistance. We describe the current radio systems developed by Shared Spectrum Company as part of the DARPA XG program and provide results from field testing and benefit studies.
Today’s Washington Post has a story, Electronic Passports Raise Privacy Issues, on the new passport card that’s part of the DOS/DHS Western Hemisphere Travel Initiative. The program is controversial since the cards use “vicinity read” radio frequency identification (RFID) technology that can be read from a distance of 20 or even 40 feet. This is in contrast to the ‘proximity read’ RFID tags in new US passports that require that the reader be within inches. The cards will be available to US citizens to speed their processing as they cross the borders in North America.
“The goal of the passport card, an alternative to the traditional passport, is to reduce the wait at land and sea border checkpoints by using an electronic device that can simultaneously read multiple cards’ radio frequency identification (RFID) signals from a distance, checking travelers against terrorist and criminal watchlists while they wait. “As people are approaching a port of inspection, they can show the card to the reader, and by the time they get to the inspector, all the information will have been verified and they can be waved on through,” said Ann Barrett, deputy assistant secretary of state for passport services, commenting on the final rule on passport cards published yesterday in the Federal Register. src”
As described in the ruling published in the Federal Register, the Government feels that privacy concerns have been addressed.
“The government said that to protect the data against copying or theft, the chip will contain a unique identifying number linked to information in a secure government database but not to names, Social Security numbers or other personal information. It will also come with a protective sleeve to guard against hackers trying to skim data wirelessly, Barrett said.” src
Of course, if you carry the card in your purse or wallet, your movements can still be tracked by the unique ID on the card. There are also security concerns since the tag’s ID may be cloned.
“Randy Vanderhoof, executive director of the Smart Card Alliance, represents technology firms that make another kind of RFID chip, one that can only be read up close, and he is critical of the passport card’s technology. It offers no way to check whether the card is valid or a duplicate, he said, so a hacker could alter the number on the chip using the same techniques used in cloning. “Because there’s no security in the numbering system, a person who obtains a passport card and is later placed on a watchlist could easily alter the number on the passport card to someone else’s who’s not on the watchlist,” Vanderhoof said.” src
I recently bought a GPS (Garmin Mobile 10) that works with my WM5 Smartphone. In the process of trying to install the Garmin Mobile XT application (which was very problematic and a huge pain, but I digress ….), I ended up uninstalling Google Maps.
When I went to download and reinstall it though, I noticed that they have a new beta feature (My Location) that shows you where you are. It can either use a GPS, or use cell tower information. Basically, it sees which cell tower your phone is signed up to (and what signals it is seeing from others), and uses this to estimate where you are to within a 1000 meters.
This is interesting, because we did it the same way back when there used to be AMPS / CDPD and Palm IIIs and Vs with cellular modems. Our project was called Agents2Go, and we published a paper about this in the MCommerce workshop of Mobicom in 01. I remember that Muthu et al from AT&T had a similar paper in MobiDE that year as well.
The problem at that time was that there was no publicly accessible database of all cell tower locations. Also, we heard informally from at least one telco that while doing this for research was Ok, if anyone ever tried to make money from it they would want to be a part of the loop. I guess Google has found a way to work with the various telcos ? Or maybe in the interim cell tower ids and locations have been made public knowledge ?
Of course Google maps also works with GPS, except that it refuses to work with my Garmin. I’ve tried all the tricks that a search on Google will reveal (mainly, setting the serial port used by Bluetooth to talk to the GPS) , but to no avail
FON (Wikipedia article) is “a global community of people who share WiFi.” The idea is intriguing and has potential, so much so that the Madrid-based startup behind just raised $22M from investors that include Google, Skype and eBay. Here’s how it is supposed to work.
“In order to become a Fonero, you go to FON, to download software that you install in your router, you place your antenna by a window and you share bandwidth with other Foneros from anywhere in the world. You can also buy the FON Ready router from our web site, plug and play. FON creates a free WiFi roaming environment for those who contribute WiFi signals, namely those who have already signed up with a local ISP and downloaded our software into their WiFi routers.”
FON currently provides software for the Linksys WRT54G/GL/GS routers. Since launching three months ago, they have added 3,000 Foneros to the network, but US coverage is still quite sparse (and nothing in the Baltimore DC area!).
Like all VC funded startups, there has to be a business plan, so what is it? If you are not a Fonero you pay to use a hotspot, probably with some kind of prepaid scheme like Skype’s. Foneros will come in two varieties: Linus’s who benefit by getting free access via any FON node and Bill’s, who don’t get free access but do get half of the payment for the users who go through their routers.
It remains to be seen how ISPs will react to this if it catches on. Most ISPs prohibit bandwidth sharing in their service agreement. Speakeasy is the only ISP who is listed as welcoming FON.
The MIT Tech reports on a plan in which MIT is collaborating with the city of Cambridge to deploy a free wireless mesh network. The article has some interesting technical details and says that the plan is based on MIT’s roofnet project, an experimental 802.11b/g mesh network in development at MIT CSAIL.
A collaboration with MIT researchers may provide Cambridge with a free, city-wide, wireless internet service as early as late summer. The project will rely on a mesh networking technology that allows individual computers to become new access points, projecting the reach of the network beyond its original antennas.
…
Traditionally, a wireless network is centralized around one wireless access point, which communicates with a wireless card in any laptop or desktop computer, Hart said. Mesh technology allows individual computers to propagate the network and act as new access points, making it unnecessary for a user to be within range of the original wireless signal, she said.
… [the wireless access points] are constructed from $15 commercial access points purchased from the software manufacturer NETGEAR, he said. The 40 milliwatt chip inside the commercial product is replaced with a 400 milliwatt chip and ‘hacked’ to include computer code that enables the mesh technology, he said.
…
The code, which is publicly available, was written by an MIT research group called Roofnet. Daniel E. Aguayo G, a Roofnet researcher, said that though they were not the first to write a code for mesh technology, they were the first to conduct a large-scale test of their software. …
FIPA is an IEEE Computer Society standards organization that promotes agent-based technology and the interoperability of its standards with other technologies. Jim Odell reports that FIPA’s P2P Nomadic Agent Working Group has released a draft of its specification. The group describes it’s focus as:
“The objective is to define a specification for P2P Nomadic Agents, capable of running on small or embedded devices, and to support distributed implementation of applications for consumer devices, cellular communications and robots, etc. over a pure P2P network. This specification will leverage presence and search mechanisms of underlying P2P infrastructures such as JXTA, Chord, Bluetooth, etc. In addition, this working group will propose the minimal required modifications of existing FIPA specifications to extend their reach to P2P Nomadic Agents. Potential application fields for P2P Nomadic Agents are healthcare, industry, offices, home, entertainment, transport/traffic.”
Technicians in Ireland are testing a device capable of skipping between incompatible wireless standards by tweaking its underlying code. A report from NewScientist states:
The device can impersonate a multitude of different wireless devices since it uses reconfigurable software to carry out the tasks normally performed by static hardware… The technology promises to let future gadgets jump between frequencies and standards that currently conflict. A cellphone could, for example, automatically detect and jump to a much faster Wi-Fi network when in a local hotspot.
I was very impressed with the 
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