Satellite TV provider Dish Network has submitted an informal $25.5 billion bid for Sprint Nextel, upping a previous offer from Japanese telecommunications company SoftBank. Dish has offered Sprint shareholders $4.76 in cash and roughly $2.24 in stock that would be financed through $17.3 billion in cash and debt financing. SoftBank offered $20.1 billion in October 2012. Sprint—the third-biggest US cellular provider with 56 million subscribers—has yet to comment on the Dish proposal. Sprint is currently the No. 3 cellphone service provider in the United States with 56 million subscribers nationwide. (ZDNet)(CNNMoney)(The New York Times)(Dish)
Tuesday, May 7, 2013
Dish Network Bids $25.5 Billion for Sprint
Monday, May 6, 2013
Is IPv6 Secure Enough?
by George Lawton
Proponents are pushing network operators and equipment makers to adopt IPv6.
Supporters say increased utilization will result in a better protocol that provides many more IP addresses for the huge number of Internet-connected devices than its predecessor, IPv4. The Internet Assigned Numbers Authority gave the last IPv4 addresses to regional Internet registries in 2011.
On 6 June this year, backers sponsored World IPv6 Launch day, during which participating websites enabled the protocol permanently. In addition, ISPs offered IPv6 connectivity and router manufacturers provided devices enabled for the technology by default.
Despite the ongoing campaign, numerous experts contend that IPv6 raises significant security concerns that adopters must address.
For example, they say, best security practices for IPv6 routers, firewalls, and spam filters have not been well developed and implemented.
There are also concerns that Windows machines now turn on IPv6 tunneling by default. With this approach, legacy IPv4 networks can carry IPv6 traffic by encapsulating and tunneling IPv6 packets across IPv4 networks.
However, this could create security problems for organizations that have such IPv4 networks but haven't deployed security measures to deal with malicious IPv6 packets.
Jeremy Duncan, senior director at security vendor Salient Federal Solutions, said there have already been several IPv6 denial-of-service (DoS) and spam attacks because many existing routers, firewalls, and other gateway devices can't protect against them yet.
"There is a small percentage of the attacker community that is knowledgeable about IPv6," said IPv6 security expert Scott Hogg, director of technology solutions at consultancy GTRI and chair of the Rocky Mountain IPv6 Task Force.
Some hackers, he added, don't even know about IPv6 vulnerabilities but launch general attacks that happen to exploit IPv6 networks' weaknesses.
The Internet Engineering Task Force began developing IPv6 in 1992 when the IETF saw that the increase in Internet activity would use up the limited number of IPv4 addresses. The group released IPv6 in 1996.
IPv4 uses a 32-bit address space, allowing for 232 — or about 4.3 billion — unique addresses.
IPv6 uses a 128-bit address space, allowing for 2128 — or about 3.4×1038 — addresses.
Google has collected statistics that indicate that IPv6 global aggregate usage has grown from 0.2 percent of all Internet traffic in early 2010 to 0.75 percent in mid-2012.
Newer operating systems and networking equipment support IPv6. However, many older IPv4 devices are still in use.
According to GTRI's Hogg, a key issue is the lack of time IT workers have spent learning about IPv6, even though their networks use the technology.
IPv6 has different security challenges than IPv4, he explained. "Most security practitioners have not invested the time to learn about these differences and formulate plans on how to secure IPv6," he said.
IPv6 code development for security is immature, according to Jeff Doyle, president of IP-network consultancy Jeff Doyle and Associates.
Vendors have just begun implementing and testing useful IPv6 security approaches, which are too new to have been proven safe, he explained.
One problem occurs because IPv6 networks create tunnels for sending traffic across IPv4 networks by encapsulating IPv6 data into IPv4 packets.
IPv4 equipment, including firewalls, cannot easily decode the traffic based on the newer protocol for security inspection.
Thus, hackers could send malware and spam that IPv4 security equipment couldn't detect.
Some older IPv6 implementations don't support newer security technologies, including those that provide built-in authentication and encryption.
Another problem is the IPv6-attack tools that people have created and posted online for use by unskilled hackers.
For example, said Salient Federal's Duncan, one prominent group — the Hackers Choice (THC) — has updated one of its tools to include exploits for LAN-based IPv6 equipment.
THC says it has done this to make public the vulnerabilities it finds so that people will fix them.
However, the toolkit also lets hackers fake router advertisements, which routers use to announce themselves on a link. Hackers could use fake RAs to overwhelm a router and thereby stall traffic.
IPv6 offers rich extension headers that carry information that promises more granular networking control in areas such as routing, data encryption, and authentication.
However, vendors are just learning how to securely support these extensions.
In one case, a researcher used an extra-long extension header to overwhelm a router, allowing potentially malicious packets through without authentication.
Older IPv6 equipment supported by default the protocol's Type 0 routing headers, designed to list the intermediate nodes at which packets will stop on the way to their destination. This is designed to improve network performance.
However, hackers could construct packets that use the Type 0 headers to travel between two routers multiple times, resulting in a DoS attack.
Newer IPv6 equipment has support for Type 0 routing headers turned off by default.
IPv6 has several security features such as IPsec, which authenticates and encrypts each IP packet used during communications.
However, Salient Federal's Duncan noted, older equipment doesn't always have IPsec turned on by default.
IEEE 802.1X provides access control via the authentication of routers trying to communicate with the network.
The IETF's IPv6 Router Advertisement Guard (RA-Guard) analyzes RAs and filters out bogus ones sent from unauthorized routers. This helps counter router spoofing.
However, Windows doesn't natively support these capabilities, so organizations must deploy RA-Guard drivers on each of their computers to protect them.
The best practices for addressing IPv6 security issues are generally the same as those used with IPv4, said GTRI's Hogg.
However, in many cases, organizations must update their networking equipment to support the latest IPv6 capabilities, said consultant Doyle.
This will entail a simple software upgrade in some cases or, for equipment using dedicated-purpose chips that can't be upgraded, a full platform change.
Moreover, Doyle said, companies must make sure their IT personnel are fully trained in IPv6 security.
Businesses could also use deep-packet inspection tools to analyze IPv6 traffic more carefully.
Some organizations are offering security bounties to help find vulnerabilities. Will Brown, associate vice president of product development for network-equipment vendor D-Link, said, "We are working directly with the security community … and have created a reward program for disclosing any issues that can be verified."
Hogg stated, "We need security vendors to address IPv6 in all aspects of their security products to provide defenders [with] protection before they deploy IPv6."
Doyle predicted IPv6 will be a major concern to IT organizations and vendors for the next couple of years, as new vulnerabilities are discovered and addressed.
But in the long run, he said, as firewalls, spam filters, and packet-inspection tools improve, securing IPv6 will become routine.
Sunday, May 5, 2013
Businesses Turn to Object Storage to Handle Growing Amounts of Data
by Sixto Ortiz Jr.
Big Data has gotten so big that traditional, hierarchical file systems are straining to keep up with today's exponential information growth.
As businesses collect more and more information — particularly unstructured data such as multimedia files — administrators are having trouble managing, indexing, accessing, and securing the material.
The challenge with traditional file systems is maintaining their hierarchical organization and central data indices as the number of files and the amount of unstructured information grows.
In response, companies are turning to object storage, which stores data as variable-size objects rather than fixed-sized blocks.
Rather than housing information that can only be found somewhere in a hierarchical system, object storage uses unique identifier addresses to locate and identify data objects, explained Russ Kennedy, vice president for product strategy, marketing, and customer relations at object-storage vendor Cleversafe.
Object stores have nonhierarchical, near-infinite address spaces, said Mike Matchett, a senior analyst with the Taneja Group, a market-research firm.
Thus, even as the amount of data grows, the storing and finding of information doesn't become more complicated.
Nonetheless, widespread object-storage use faces several challenges.
Traditional storage systems house data in fixed-size blocks in directories, folders, and files. There is a limit to how many files can be housed in this hierarchical system, said Jeff Lundberg, Hitachi Data Systems' senior product marketing manager for file, content, and cloud.
Users can't go directly to information but instead must work via a central index, noted Janae Stow Lee, senior vice president of the File System And Archive Product Group at storage vendor Quantum Corp.
A complicating factor is that because of the increase in multimedia, Kennedy noted, file sizes are growing to the gigabyte and even terabyte range.
As the amount of data and number of files have grown, current storage systems have become very large, explained Tom Leyden, director of alliances and marketing for object-storage vendor Amplidata. This makes finding information in their huge hierarchies increasingly difficult, he said.
The difficulty of trying to find data via increasingly large indices limits the number of files and amount of data traditional storage systems can work with, said the Taneja Group's Matchett.
And as traditional systems store more data, they become more likely to experience mechanical drive failure. Administrators then must copy data to additional systems to guarantee reliability and availability, which could be cost prohibitive for some organizations.
Added Quantum's Stow Lee, as information volumes grow, traditional file systems' data-replication approaches become too expensive and time-consuming to use.
Data backups also become costly, which could create serious problems for organizations that need timely recovery points, noted Tad Hunt, chief technology officer of storage vendor Exablox.
Many companies are using storage-area networks and network-attached storage to cope with spiking data volumes, but these approaches typically use hierarchical file systems and thus are also beginning to experience problems, noted Ross Turk, vice president of community at storage consultancy Inktank.
Work on object-storage technology began in 1994 at Carnegie Mellon University and has been supported over the years by the National Storage Industry Consortium and the Storage Networking Industry Association.
However, there was no big need for object storage until recently.
Numerous vendors — such as Amplidata, Caringo, Cleversafe, DataDirect Networks, Exablox, and Quantum — are now developing and selling object-storage products.
Searching for specific content in a large traditional file hierarchy requires analysis of the entire index and the reading of long lists of nodes and their contents, explained Dustin Kirkland, chief technology officer at Gazzang, a security and operations diagnostics company.
This process can consume considerable time and CPU resources, he noted.
Many organizations are thus turning to object storage, which uses the same types of hardware systems as the traditional approach but stores files as objects, which are self-contained groups of logically related data. The information is stored nonhierarchically, with an object identifier and metadata that provides descriptive attributes about the information.
Applications that interface with object-storage systems use identifiers to access objects easily and directly, wherever they are. The objects thus aren't tied to a physical location on a disk or predefined organizational structure. To applications, all of the information appears as one big pool of data.
There is no large central index that users must work through to access data. These indices act as a bottleneck in traditional storage systems, noted Quantum's Lee. Not using indices lets the object-based systems add storage hardware and scale well.
Object systems' identifiers contain more metadata than traditional storage files. According to Amplidata's Leyden, this makes finding data much easier for searchers.
This also lets companies apply detailed policies — such as file-access controls — to objects for more efficient and automated management.
Object storage also simplifies data management and use because administrators don't have to organize and manage hierarchies, according to Cleversafe's Kennedy.
And, he said, the systems are less expensive to set up and operate because they are less complex and highly scalable, and also require fewer administrators.
Object storage — which enables easier, quicker data access than traditional systems — saves money because it can work with slower, less expensive drives without losing performance.
Object-based systems typically secure information via Kerberos, Simple Authentication and Security Layer, or some other Lightweight Directory Access Protocol-based authentication mechanism, Kennedy noted.
Object storage systems' scalability; suitability for use with lower-cost, high-capacity hard drives; and improved automation make the approach good for cloud computing, he said.
Because it is highly scalable and enables easy information access even from large data collections, object storage is best for large unstructured files such as those containing multimedia.
The approach is good for unstructured data also because this type of information doesn't always fit easily into the hierarchical systems that traditional storage houses.
Currently, Leyden said, object storage is used mostly in cloud applications like Dropbox, Amazon's Simple Storage Service, and Google's Picasa photo-storage program. These applications form the basis for cloud-based services such as file sharing, backups, and archiving.
The widespread use of object storage faces several challenges.
Some companies have to rewrite their application interfaces to use object-storage APIs natively, said Quantum's Lee.
The security and privacy of data in object-storage systems is an important issue, said Gazzang's Kirkland.
He explained, "All information should, without question, be encrypted before being written to disk. Object storage without comprehensive encryption should be as unfathomable in 2012 as a minivan without seat belts."
According to Matchett, object-storage use is already spreading, particularly in public and private cloud implementations.
Jeffrey Bolden, Managing Partner at IT consultancy Blue Lotus SIDC, said object storage will remain a niche technology.
He noted that traditional file systems enforce relational integrity — which ensures that relationships between tables remain consistent despite any changes that may be made to information in the database — while object storage doesn't.
Quantum's Stow Lee said object storage will be a niche application at first—primarily for customers needing at least 500 terabytes of storage—but then will be widely adopted as the technology improves and cloud services grow in popularity.
However, she added, no storage technology is best for all uses, so traditional file systems will still be around.
Saturday, May 4, 2013
Nanomedicine: a new frontier
Artist’s conception of membranes forming on a gold ?lm with nanopores. Membranes are delivered asballoonlike vesicles that break open on contact to form ?at sheets. Green circles are proteins embedded in
the membrane that extend down into the nanopores. Biosensors can detect and characterize the interactions between membrane proteins and molecules such as antibodies.
Everything our bodies do depends on interactions that happen on a nanoscale, the realm of atoms and small molecules. Today, medicine is catching up.
At the University of Minnesota, nanomedicine researchers are pushing forward with projects like new drug-delivery technologies and better screening of potential drugs.
April 29, 2013
Feature
Nanoparticles against cancer
In cancer biology, for example, mechanical engineering professor John Bischof, chemistry associate professor Christy Haynes, and radiology professor Michael Garwood are out to deliver nanoparticles of iron oxide to tumors and kill them with heat while sparing healthy tissue.
“We want to get the temperature of the nanoparticles above 45 degrees C [113 F],” says Bischof, whose expertise is heating measurements.
This is possible by applying alternating magnetic fields around the nanoparticles inside living tissue. The applied fields make the particles’ magnetic fields flip direction quickly, or they roll the particles back and forth, creating friction. These motions heat the particles within tumor cells that contain them, but not normal cells, which don’t.
Ideally, the team would inject enough iron oxide into a tumor to achieve more than 1 milligram of iron per gram of tumor tissue. It is important to know how many of the nanoparticles have been absorbed by a tumor so as not to overtreat.
“Unfortunately, clinical imaging like ultrasound or computed tomography [CT] can’t accurately measure iron concentrations in that range,” Bischof says.
However, at the U’s Center for Magnetic Resonance Research, Garwood has developed SWIFT, a new technology that can. At present, no other imaging technology is capable of this, Bischof says.
To improve stability and heating properties, Haynes applies coats—10-20 nanometers thick—of a special “mesoporous” silica. This silica naturally contains pores, into which molecules of anti-cancer drugs can be added for a one-two punch.
Dartmouth College researcher Jack Hoopes depends on this work as he, along with physicians, move toward bringing iron oxide thermo-therapy to patients. Clinical trials with breast cancer patients are scheduled to begin this year.
Are they toxic?
Nanomedicine also concerns the toxicity of nanoparticles. When inhaled in quantity, they can be harmful. But what if they’re ingested and get into the bloodstream?
Christy Haynes has tested commonly used nanoparticles—made from silica, titanium, gold, and silver—for toxicity to several types of cells from the immune systems of lab animals and humans.
“With the four types of particles, we almost always see 80 percent viability of the cells,” she says. In other words, the cells held up pretty well. Haynes hopes to learn if this result will apply to other cells with similar functions. She also wants to answer big questions like: How long do nanoparticles last in the body? and How are they excreted?
Drug screening
If a drug is to elicit some response from a cell, it first must interact with a protein “receptor” embedded in the cell’s outer membrane. A good candidate drug is one that interacts strongly, but measuring the strength of interactions is inefficient because most tests in use only tell whether or not an interaction occurs.
But that’s about to change.
“We’re developing optical sensors to study how proteins interact with molecules,” says Sang-Hyun Oh, an associate professor of electrical and computer engineering. “Membrane proteins are the main targets.“
Oh and his colleagues have developed a way to fabricate ultrathin gold films containing nanoscale pores in a precise array. In experiments, they lay a membrane containing receptors over a film, with the receptors protruding from the membrane both downward into the pores and upward. Next, they add a candidate drug to be tested.
Under laser light, electrons in the gold atoms resonate and funnel the light down the pores and into a detector. This response is very sensitive to how a drug candidate interacts with a receptor.
Oh and his team created the instrument that measures the interaction strength. They are collaborating with Mayo Clinic neuroscientists who have developed antibodies to potentially treat multiple sclerosis by restoring neurons’ myelin sheaths, which the cells need to function normally.
“With rodents, we found that the antibodies attached to membranes of [myelin-forming cells] and triggered them to initiate repair,” says Oh.
Without Oh’s group, the Mayo Clinic scientists would have to rely on costly, inefficient testing of the antibodies they produce. Clinical trials with MS patients will begin soon.
Tags: College of Science and Engineering, Academic Health Center
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TK Recommends
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UM News (2013).
Nanomedicine: a new frontier
University of Minessota
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IMPORTANT NOTICE
Friday, May 3, 2013
What does the Muse CD cover have to do with Medical Imaging?
This is Muse CD cover of their 6th album: "The 2nd Law":
Indeed, this image is truly beautiful and remarkable. It is an image of the white matter fibers in the brain obtained with diffusion MRI (link). The image was obtained by the Human Connectome Project, which is a 5-year project funded by NIH to find the networks of the human brain. These networks will show how our brain communicates between different regions and give insight about the anatomical and functional organization of the brain. The project also has the goal to produce data that will help understanding brain diseases such as Alzheimer's disease. The data is available to the scientific community.
Indeed, this image is truly beautiful and remarkable. It is an image of the white matter fibers in the brain obtained with diffusion MRI (link). The image was obtained by the Human Connectome Project, which is a 5-year project funded by NIH to find the networks of the human brain. These networks will show how our brain communicates between different regions and give insight about the anatomical and functional organization of the brain. The project also has the goal to produce data that will help understanding brain diseases such as Alzheimer's disease. The data is available to the scientific community.
So how do you obtain these networks? By applying computer algorithms to data obtained with different neuroimaging techniques: MRI, fMRI, diffusion MRI among others. These computer algorithms come from the graph theory. The application of these algorithms is extremely useful, because the algorithms analyze the network, reduce the complexity, find similarities and differences between different networks.
A very nice science article for researchers not familiar with the topic:
http://www.sciencemag.org/site/products/lst_20130118.xhtml
To know more about obtaining diffusion MRI data or network methods, look into these two articles:
- Hasan, K., Walimuni, I., Abid, H., & Hahn, K. (2011). A review of diffusion tensor magnetic resonance imaging computational methods and software tools Computers in Biology and Medicine, 41 (12), 1062-1072 DOI: 10.1016/j.compbiomed.2010.10.008
- Kaiser, M. (2011). A tutorial in connectome analysis: Topological and spatial features of brain networks NeuroImage, 57 (3), 892-907 DOI: 10.1016/j.neuroimage.2011.05.025
Thursday, May 2, 2013
Tartaglia-Pascal triangle and quantum mechanics
The paper I wrote with Alfonso Farina and Matteo Sedehi about the link between the Tartaglia-Pascal triangle and quantum mechanics is now online (see here). This paper contains as a statement my theorem that provides a connection between the square root of a Wiener process and the Schrödinger equation that arose a lot of interest and much criticisms by some mathematicians (see here). So, it is worthwhile to tell how all this come about.
On fall 2011, Alfonso Farina called me as he had an open problem after he and his colleagues got published a paper on Signal, Image and Video Processing, a journal from Springer, where it was shown how the Tartaglia-Pascal triangle is deeply connected with diffusion and the Fourier equation. 
People working in quantum physics are aware of the difficulties researchers have met to link stochastic processes a la Wiener and quantum mechanics. Indeed, skepticism is the main feeling of all of us about this matter. So, the question Alfonso put forward to me was not that easy. But Alfonso & al. paper contains also a possible answer: Just start from discrete and then go back to continuum. So, the analog of the heat equation is the Schrödinger equation for a free particle and its kernel and, indeed, the evolution of a Gaussian wave-packet can be managed on the discrete and gives back the binomial coefficient. What you get in this way are the square root of binomial coefficients. 
Then, I thought that this connection could be deeper than what we had found. I tried to modify Ito calculus to consider fractional powers of a Wiener process. I posted my paper on arxiv and performed both experimental and numerical computations. All this confirms my theorem that the square root of a Wiener process has as a diffusion equation the Schrödinger equation. You can easily take the square root of a natural noise (I did it) or compute this on your preferred math software. It is just interesting that mathematicians never decided to cope with this and still claim that all this evidence does not exist, basing their claims on a theory that can be easily amended.
We have just thrown a seed in the earth. This is our main work. And we feel sure that very good fruits will come out. Thank you very much Alfonso and Matteo!
Farina, A., Frasca, M., & Sedehi, M. (2013). Solving Schrödinger equation via Tartaglia/Pascal triangle: a possible link between stochastic processing and quantum mechanics Signal, Image and Video Processing DOI: 10.1007/s11760-013-0473-y
Marco Frasca (2012). Quantum mechanics is the square root of a stochastic process arXiv arXiv: 1201.5091v2
Farina, A., Giompapa, S., Graziano, A., Liburdi, A., Ravanelli, M., & Zirilli, F. (2011). Tartaglia-Pascal’s triangle: a historical perspective with applications Signal, Image and Video Processing, 7 (1), 173-188 DOI: 10.1007/s11760-011-0228-6
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