Once a computer has been infested, it waits for orders from criminal bot herders, who turn these zombie computers into massive bot networks that spew spam and other malware across the Internet.
You may not be able to block the botnet invasion completely, but with layers of bot-hunting technologies and common sense, you can minimize the effect on your network.
'Everybody Gets Bots'
Before you can battle the bots, you've got to understand the scope of the problem. "We've been in denial about the scale of the problem,'' says Michael Barrett, CISO of PayPal in San Jose, Calif.
In fact, in a recent survey of 394 Network World readers responsible for network security, a surprising 43.7% said that compromised clients were not a significant problem. Another 30.2% said that they have not seen evidence that any computer on the network has ever been infected.
Just because nearly three-quarters of respondents aren't on high alert, it doesn't mean the threat isn't there, says Rick Wesson, CEO of Support Intelligence, a San Francisco firm that tracks bot outbreaks. On any given day, his company's honeypot will trap all kinds of insidious and fraudulent spam coming from zombie clients.
"The deal is that these bot herders are pretty smart, operating systems are very vulnerable, and everybody gets bots. Most companies run pretty tight networks, but the idea that you are not going to have bot networks running on your systems is naive. We have a lot of data that says a sizable portion of the Fortune 1000 has bots," he says.
If the Fortune 1000 can't stop bots, smaller organizations and consumers don't have a prayer. The little guys have fewer resources to perform security updates or to monitor their networks and machines for strange traffic patterns, says Ken Lloyd, director of security for security service provider Cyveillance in Arlington, Va. Consumers are at the highest risk because they tend to have the least security, Lloyd says.
"Enterprises have the problem, too, no doubt about it," says Martin Roesch, CTO of intrusion-detection software-maker Sourcefire. Enterprises are most vulnerable to roving machines that aren't properly set up to fight off malware attacks. "That's when there's trouble -- it's people getting spammed over [instant messaging], or Trojans and viruses over IM, or getting these things in their in-box, or surfing where they shouldn't be with vulnerable versions of [Internet Explorer] and Firefox," he says.
In fact, Gartner predicts that 75% of enterprises will be infected by bots by year-end.
Criminalization of the Internet
In the past year, bot herding has taken a disturbing turn to organized criminal activity aimed at making money. The stereotypical teenager out for ego-gratifying distributed denial-of-service attacks is a thing of the past.. For example, a high-profile arrest in London last summer involved a 63-year-old, a 28-year-old and a 19-year-old. These people are more organized, more professional and more interested in stealth.
"The amount of effort involved in this would literally take a distribution channel. You have the people making it, the people selling it, the people using it. One person could not do this entire thing from creation to use. Script kiddies are out of the question," Lloyd says. "The people who are running these things are basically into organized crime."
Specifically, bot herders are launching high-paying scams, such as spam, identity theft through keylogging (capturing keystrokes to learn users' names and passwords), click fraud (automatically clicking on ad banners for which advertisers pay per click) and warez (the distribution of pirated software).
The scale and the amount of money involved can be enormous, researchers say. For instance, click fraud accounts for about 14% of all clicks and as much as 20% of the higher-priced ads, ClickForensics says. It cost advertisers an estimated $666 million last year, research firm IncreMentalAdvantage says. The Business Software Alliance claims that a quarter of the world's software is pirated, amounting to billions of dollars in losses for software makers.
Black-market servers -- where people buy, sell and contract for botnets -- are flourishing.
"Bots are a big part of the underground economy. . . . It's a new twist, an explosion that we've seen in the last six months or so," says Oliver Friedrichs, director of emerging technologies for Symantec Security Response. These servers are also the place where criminals sell stolen information obtained from their bots, such as credit card numbers.
Battle of the Botnets
Because bot herders obviously spend resources managing and running their botnets, they have become less interested in increasing the number of networks they manage. Symantec reports that the number of command-and-control servers diminished by 25% in the second half of 2006, which indicates that bot herders are consolidating and making each network larger, the company says.
Strange new attacks have caused security researchers to speculate that bot herders are engaged in turf wars and attacking each other. The goal of some malware may be to disable rivals' drones; in the process, that causes havoc with networks. For instance, one recent worm was directed at machines that had visited a malicious pump-and-dump Web site. It infected the machines with a virus that caused them to reboot continuously, rendering them useless for legitimate work (and illegitimate uses), Web-monitoring firm Websense reports.
Because bot herders are more interested in keeping their millions of infected machines secret, they will activate a machine, blast the spam or run the click-fraud game and quickly shut the connection down. Rootkit infections operate invisibly to the operating system. And bot herders control their machines via HTTP (not necessarily relying on Internet Relay Chat); that means detecting bots on your network is hard to do.
Social-networking Diseases
More worrisome still is that today's bot herders use such techniques as toxic blogs, cross-site scripting and iFrames, which do not require a user to take any action, such as clicking on an e-mail attachment, to become infected.. If a PC with a vulnerable operating system or browser visits a Web site or blog that contains malicious code, it is secretly infected. Malicious JavaScript, sometimes in adware, is downloaded automatically to the PC. Then it's directed to other malicious Web sites to receive its commands, and the bot is in business. With the popularity of inexpensive Web-hosting based on shared servers, a hacker can use a single operating-system vulnerability to gain access to dozens of Web servers.
Toxic blogs and cross-site scripting, which involve planting malicious code into an otherwise legitimate site, have been around for years. Bot herders are finding new ways to make use of them, however. Among the more infamous instances was the bot herder who hacked into the Dolphins Stadium Web site just before the Super Bowl -- a time when thousands of people would be trying to buy tickets.
Social networks, too, can become cesspools of malware, because these networks let users upload and share files, data and other potentially harmful code. With iFrames, invisible frames can be used to download undetected malware automatically on compromised Web sites, as well as on blogs and social networks.
"Web sites and social-networking sites -- there's so much personal information on these sites and so many users, it's just a gold mine of info," says Chris Boyd, director of malware research for FaceTime Communications, a Web-monitoring company specializing in protecting real-time applications, such as IM and VoIP.
Sunday, December 16, 2007
Friday, August 24, 2007
Know your DVD player
Have a DVD player like everyone has but never have seen what it’s capable of? Its a device that sits quietly on the table top, spinning discs, sometimes shining, blinking to give you an idea its from another planet. It’s a DVD player but plays everything you throw at it. If I am not mistaken, all the time it’s switched on, 1% of the time it plays DVD’s and the rest, you throw at it, it plays. Now its being around for the longest time ever and is ready to be overshadowed by the Blu- Ray players and the HDDVD players but yet, many of them are clueless what it is.
I always like to act innocent, so once I decided let me see how many of them know their gadgets better. Now which gadget to choose. I found everyone has a DVD player, so now the contest officially began. The questions will not be mentioned here but I have the answers what people gave me. “DVD’s are very clear”, “My DVD player plays everything so clearly that even VCD’s look very clear”, “The best part of my DVD player is I can now experience Dolby Digital with everything I play”
Now I was laughing from inside but again as I like to act innocent, that smile never was shown up on my face. The best part is I asked the person who said that the VCD’s look very clear like a DVD, that how many DVD’s do you watch in a month and the answer is “I never had to put in a DVD in my player as the VCD’s look so clear. Now I won’t act stupid by criticizing people but yes I would like to educate people as what is a DVD player and how to make use of it to the fullest.
Let’s begin with knowing the DVD player better
There is no doubt that DVD player is the hottest selling product these days. In
Today’s DVD players can play wma, mp3, Divx, and so on, but the players that command a premium that also play DVD Audio, SACD. DVD as a format is a successor of VCD’s that had content stored in MPEG 1 format. A resolution of 352 x 288 pixels and frame rate of 25 frames/second. With advertisements seen in the media, print everyday of resolutions as high as 1080p this resolution seems to be poor. DVD overshadowed VCD’s. With an impressive specification as compared to VCD’s they had no place to go. With a resolution of 720 x 576 pixels MPEG2 (Called Full-D1) images on a DVD were much clear and good DVD players displayed them with much precision. Coming down to the Audio Specs of DVD we see that with a sampling rate of 48000 Hz and Up to 8 audio tracks containing Dolby Digital, DTS, PCM(uncompressed audio), MPEG-1 Layer2. That is much superior to VCD’s. Let’s also have a look at MP3’s. You might be surprised what MP3 is doing here but at the later part you will get a hint of what I am trying to say. (MPEG-1 Audio Layer-3) Is the standard technology and format for compressing a sound sequence into a very small file while preserving the original level of sound quality when it is played.
Well that’s was just a round of introduction, lets begin with the story. DVD player will cost you round about Rs. 2500/- and also goes as high as Rs. 4, 99,999/- and much higher as well. But again isn’t it just a DVD player that plays DVD’s? So why pay lakhs of rupees for it? Well I don’t want people to sell their valuables and get that costly DVD player. Leave them for us Videophiles who are ready to sell our Kidney any time to get such a Gadget (well don’t eye on my 2nd kidney as let me live and experience what I have purchased in exchange of my kidney)
A DVD player on its front fascia has a tray to accept 1 DVD at a time and they are slim, with minimal buttons somewhere on the top or in the front and a host of buttons on the remote control. In the back of the DVD player again you will have a lot of connectors in different colors making you wonder when I need 3 pins why do I have 20 or more in the back. Now the front fascia is decorated will lot of logos that say Dolby Digital and DTS digital out in basic DVD players. Well a lot of them also say MP3, WMA and MP4 as well.
Expectations
What should we expect from a DVD player? This is the most stupid question anyone would ask. How can you buy a car and not expect something from it other than just moving from one place to another. With DVD players we are talking about the clarity of the picture and sound in general. Now again I am not asking you to evaluate, but just enjoy the quality that an original, well mastered DVD would give you. Original DVD’s are now very cheap. With Moser Baer and T Series coming up with DVD’s as cheap as 35 rupees this is what you can start with. These DVD’s are any time better that any VCD or even the pirated DVD that you get for 12 rupees anywhere that has 4 to 5 movies stuffed with pathetic picture quality and bad Media to make you DVD players lens life worse.
You might also come up with DVD’s as costly as 600 rupees to 999 rupees. Now do not judge a book by its cover and never judge a DVD by its price. But generally these are imported DVD and a lot of care is taken while mastering the DVD and their picture quality generally is better and these DVD’s are again collector edition DVD’s. (This comment should not be used to judge the picture quality by its price)
Performance
Take for example a decent DVD player priced at 7000 rupees and a reference grade DVD (Finding Nemo Collectors edition for eg) is being played in a DVD player. Now the DVD player has a reputation of displaying awesome images for the price tag it has to offer. But the scenario is the DVD player is connected to the television with composite connections. Now the images are damn clear and the end user is very happy of what he is seeing, but do you know you could have enhanced the picture quality by just changing the connections. In a regular DVD player we see that there are 3 types of connectors namely, Composite (widely used), S Video (rarely used) and Component (used only when component cables are supplied by the OEM). Component connectors are far more superior to S Video and S Video is far more superior to Composite. Composite connection is the one that you see on the back of the DVD player with yellow, white and red connector. S Video is the big round connector that looks like an alien. Component is the one on the back of the DVD player that is symbolized with red, green, blue color. When the DVD player is connected too the TV that has a component in, the pictures are displayed with ultimate clarity as compared to Composite connection. That was on the video part. Now not only connections do make a difference. Component connections are not widely used because it’s seen that manufacturers do not pack the DVD player with a component cable and they expect consumers to buy them separately. No doubt, because still 80% of the televisions do not have a component in, but only have composite, so it makes sense for manufacturers to pack the box with the widely used connector and do some cost saving. DVD as a media also plays an important role in determining the final output. A pirated DVD from the street has a camera print or has a pathetic video transfer done. Now genuine DVD’s have a better video transfer done in the studios and hence the picture quality is better. So the final word is get/ rent a better and a genuine DVD that will also enhance the life of y0ur player and will also get you a better picture quality and sound and you will do your bit in reducing piracy.
Audio
DVD is mastered to give you better audio than VCD’s. DVD’s are authored in Dolby Digital, DTS and others. Now to experience the effect to the fullest you need to have a DVD player that can decode these signals. That’s when you need to look at the front fascia before buying a player. If it says Dolby Digital then that means that when you insert a DVD whose soundtrack is in Dolby Digital then your DVD player will be able to read those signals and send them ahead. To experience Dolby Digital to the fullest you need to have 5 speakers and 1 subwoofer to the minimum and not 2 speakers of the television. Now what if your DVD has its sound track in DTS and your DVD player has a logo that says DTS digital out, then that means that your DVD player will not decode signals but will help you connect the DVD player to an external decoder that has a DTS decoder. Beware this is the common mistake that consumers make thinking that their DVD player can decode DTS bit stream as well. The logo you need to look for is DTS digital surround. Again you need 5 speakers and 1 subwoofer to enjoy it to the fullest and not 2 speakers.
Quality
DVD as a medium uses MPEG 2 compression and the video and Audio is not that compressed as VCD’s and the compression Is better that means that compression with minimum loss as compared with the original. So the more you compress you know what happens to the sound /picture quality, but we still need compression because the raw format is that huge, cannot fit in the media that we use commercially. Take for example MP3 that we were talking about are again compressed medium. See the difference doesn’t the Audio CD always sound better, open, airy as compared to MP3? So as much data is not compressed in a DVD the final output is much better than a VCD for example. Why VCD again for that matter avi files, xvid or anything that you say that is compressed. But again AVI files are pirates favorite. They give you 75% of the thrills of a DVD without much pain but again that is compression and a compromise of quality. With original DVD’s made available so cheap why would anyone go for an AVI print, if I had to believe that?
Again this was written in keeping the general audience in mind so no advanced technology is discussed. I thought of keeping things simple, but at the same time I expected the crowd to at least know a bit of what I am talking or Google it. This is very basic so that in my next post I can explain a DVD player in detail and by that time who had already gone through this will definitely know what I am talking about.
Subscribe to:
Posts (Atom)