Overlay network by Ms.Kajal Sharma (Lecturer, CS/IT)

With the rapid advancement of Internet and computing technology, much more aggregate information and computing resources are available, overlay networks provides better utilization of growing Internet information and resources. Overlay network brings more flexibility to add higher layer functionalities for today's Internet to support Quality of Service (QoS). Overlay network is virtual communication structure that is logically laid over a physical network. Nodes in overlay network can be thought of as being connected by virtual or logical link, each of which corresponds to a path, perhaps through many physical links, in the underlying network. An overlay network has also been proposed as a way to improve Internet routing such as through quality of service guarantees to achieve higher-quality streaming media. Overlay networking capability can be used to enhance features like overlay multicast at application service level.

Figure 1
Figure 1 demonstrates an overlay network. An overlay network has a virtual topology, which exists by the agreement of the overlay nodes. Packets are transmitted only along the virtual links between the overlay nodes using the underlying unicast mechanism provided by IP. In contrast to the Internet, in which routers are a shared resource that cannot be specialized for a particular purpose, the members of an overlay network may provide specialized services specific to the application at hand. An Overlay Network is a set of tunnels formed among network edges to support a common packet processing function other than the ones supported in the conventional network. The primary advantage of the overlay network architecture is that it does not require universal network support to be useful. This enables faster deployment of desired network functions and adds flexibility to the service infrastructure, as it allows the co-existence of multiple overlay networks each supporting a different set of service functions. An Overlay Multicast Network is one type of overlay network that provides multicast services to end users on top of the general Internet unicast infrastructure.
Overlay networks allow both network developers and application users to easily design and implement their own communication environment and protocols on top of the Internet, such as data routing and file sharing management. Data routing in overlay networks can be very flexible, quickly detecting and avoiding network congestions by adaptively selecting paths. The high connectivity of increasingly more end-nodes to join overlay networks enables effective sharing of a huge amount of information and resources available on the Internet. QoS (Quality of Service) is one of the most important unsolved research issues in this area.
Overlay networks such as the Chord, Pastry and Content Addressable Network (CAN), create a virtual topology on top of the physical topology. The overlay multicasting approach assumes no multicasting support in the network layer, and constructs a multicast delivery tree in the application layer. The overlay multicast tree consists of IP tunnels connecting edge routers in the network. IP Multicast is the traditional method for group communication over the Internet. Overlay Multicast, a substitute technology for IP Multicast has become a good topic for researchers.

NANOROBOTICS by Abhishek Kumar (4th sem, EC)

Nanorobotics is the technology of creating machines or robots at or close to the microscopic scale of a nanometer (10-9 meters). More specifically, nanorobotics refers to the still largely hypothetical nanotechnology engineering discipline of designing and building nanorobots. Nanorobots (nanobots, nanoids, nanites or nanonites) would be typically devices ranging in size from 0.1-10 micrometers and constructed of nanoscale or molecular components. As no artificial non-biological nanorobots have yet been created, they remain a hypothetical concept.
Nanorobotics theory Since nanorobots would be microscopic in size, it would probably be necessary for very large numbers of them to work together to perform microscopic and macroscopic tasks. These nanorobot swarms, both those which are incapable of replication (as in utility fog) and those which are capable of unconstrained replication in the natural environment (as in grey goo and its less common variants), are found in many science fiction stories, such as the Borg nanoprobes in Star Trek. The word "nanobot" (also "nanite", "nanogene", or "nanoant") is often used to indicate this fictional context and is an informal or even pejorative term to refer to the engineering concept of nanorobots. The word nanorobot is the correct technical term in the nonfictional context of serious engineering studies.
Some proponents of nanorobotics, in reaction to the grey goo scare scenarios that they earlier helped to propagate, hold the view that nanorobots capable of replication outside of a restricted factory environment do not form a necessary part of a purported productive nanotechnology, and that the process of self-replication, if it were ever to be developed, could be made inherently safe. They further assert that free-foraging replicators are in fact absent from their current plans for developing and using molecular manufacturing.

In such plans, future medical nanotechnology has been posited to employ nanorobots injected into the patient to perform treatment on a cellular level. Such nanorobots intended for use in medicine are posited to be non-replicating, as replication would needlessly increase device complexity, reduce reliability, and interfere with the medical mission. Instead, medical nanorobots are posited to be manufactured in hypothetical, carefully controlled nanofactories in which nanoscale machines would be solidly integrated into a supposed desktop-scale machine that would build macroscopic products.
The most detailed discussions of nanorobotics, including specific design issues such as sensing, power communication, navigation, manipulation, locomotion, and onboard computation, have been presented in the medical context of nanomedicine by Robert Freitas. Although much of these discussions remain at the level of unbuildable generality and do not approach the level of detailed engineering, the Nanofactory Collaboration[3], founded by Robert Freitas and Ralph Merkle in 2000, is a focused ongoing effort involving 23 researchers from 10 organizations and 4 countries that is developing a practical research agenda specifically aimed at developing positionally-controlled diamond mechanosynthesis and a diamondoid nanofactory that would be capable of building diamondoid medical nanorobots.
Nubot is an abbreviation for "Nucleic Acid Robots." Nubots are synthetic robotics devices at the nanoscale. Representative Nubots include the several DNA walkers reported by Ned Seeman's group at NYU, Niles Pierce's group at Caltech, John Reif's group at Duke University, Chengde Mao's group at Purdue, and Andrew Turberfield's group at the University of Oxford.

5 Ways to Avoid Adware and Malware by Manish Kasera (6th sem, IT)

Most people have systems in place to protect their computers and vital information when they’re browsing the Internet. However, with new adware and malware threats identified regularly, any browsing can leave a computer exposed, especially if the user is unaware of what to look out for. Since adware and malware removal are more difficult than prevention, it makes sense to be educated and prevent a malware infection before it happens.

First, it’s important to distinguish between adware and ad-supported software. Ad-supported software is considered a legitimate alternative for consumers who do not wish to pay for software such as games and utilities. With ad-supported software, the ad is actually part of the software application and the user clearly understands they will be presented advertisements in exchange for free use of the software.

These ads are often displayed in the application screen or are text-based links. Ad-supported software generally does not employ ad formats like pop-ups and pop-unders. Upon exiting the software, the ads disappear. Quite often, the user has the option of disabling the ads by purchasing the software outright.
Adware, on the other hand, is often installed unknowingly by a user and presents advertisements externally to the software that generates them. The software that generates these ads is installed on the user’s computer, and users often will not know what generated the ad or how to stop the ads from being displayed. Ads delivered by adware are often shown as pop-ups or pop-unders. However, not all pop-ups and pop-unders are generated by adware; some are legitimate advertisements, known as site-based ads that come from a web site and not from software on the computer.

Adware is considered by most people to be a form of malware, specifically a form of spyware. Spyware, in its most benign form, monitors the Internet browsing habits or tendencies of the user. These habits are sent back to the originator, who then uses that information to send the user even more “targeted”, and sometimes annoying, ads.
Once on a system, spyware secretly installs itself and goes to work. Spyware is often very difficult for the average user to remove. While spyware infections are purposefully difficult to identify, there are some signs that it exists: for example there can be unwanted changes to homepage settings, new wallpaper backgrounds, new screensavers, or additions, deletions or alterations to security settings and favorites list.

Other signs of a spyware infection include pop-up ads that aren't related to usually-visited web sites, commonly manifested in advertisements that are adult content in nature or, believe it or not, advertisements for anti-virus or other anti-malware software commonly known as rogue software.

Anti-spyware software works by identifying spyware installed on a system and removing it. Since spyware is installed like any other application it will leave traces of itself in the system registry and other places on the computer.
It is important to remember that not all companies who claim their software is malware-free are really telling the truth. There is always a chance that adware, spyware, or other malware is in disguise so to speak, and that programs with embedded spyware may not state its existence at all.

Always stay on the side of caution and be sure to research privacy policies and licensing agreements that come with freeware, and become familiar with Internet lists of companies reported to be using spyware such as the one published by StopBadware.org. Much like a firewall or anti-virus program, anti-spyware software is crucial to maintain optimal protection and security on a computer or network.
Malware, on the other hand, is intended to not only access a computer without the owner’s consent, but is created either to damage it, use it for illicit purposes, or to steal personal information. This category includes all kinds of viruses, worms, Trojans, root kits, and the like. Anti-malware software that uses some form of heuristics to identify and stop bad programs before they can infect are a best bet.

Be most careful when considering downloading anything off the Internet, and if doing so, consider these five tips to ensure that playing it safe is playing it smart!

1. Be proactive – Have inbound and outbound firewall-enabled plus antivirus and anti-spyware software installed. This will alert that someone is trying to access a targeted computer to put software on it. Major antivirus companies have adware and malware protection combined. Norton and CA are popular suite options. AVG, Avira and Avast, offers free stand-alone anti-virus software while Lavasoft and SuperAntiSpyware offer free stand-alone anti-spyware software.
It’s also a good idea use a broadband router instead of directly connecting your computer to a high-speed modem. Most broadband routers include a hardware firewall which provides additional protection. Finally, ensure that you have all the latest security updates for your operating system and applications by visiting the manufacturer’s websites or turning on automatic updates.

2. Stick to familiar websites – When searching for common information, make sure it is from a reputable source. If during the search the site that pops up is not recognized, at the very least, be wary of the links and downloads offered on that site. Popular, heavy-traffic sites such as About, YouTube, MSN, Yahoo, Wikipedia, and any number of familiar news sites are sure to be safer bets.

3. Download from reputable sites – Downloading presents the greatest danger of introducing adware or malware into a system. Accidentally downloading an unwanted program instead of the one that is really wanted is a common mistake. As well, downloading one program, only to have it bundled with potentially unwanted software program can be a common problem. Reputable downloads sites like CNET Download.com, Softonic and Softpedia offer editor and user ratings for more insight into other people’s experiences with a particular program.

4. Check for unfamiliar programs – Every now and then, it’s a good idea to check the applications programs listed in the computer control panel to see if there are programs that you don’t recognize. If something doesn’t look like it belongs there and it can be identified as unnecessary, remove it. If it cannot be determined what exactly it is, search for that particular program online, or run a scan with one of the options outlined in step five.

5. Run regular scans – Anti-virus and anti-spyware software should be running regular and automatic system scans to detect issues. Real-time protection should be turned on as well as automatic updates. Research continues to show that people are commonly infected by malware simply because it was not up-to-date.
By following these five guidelines, you can increase your chances of staying safe online. Additionally, certified experts such as BluePhone can help with these five guidelines to ensure that proper precautions are taken with properly installed protection. And in the event that a mistake has been made, they can uninstall malicious programs and make everything right again.