TECHNOLOGY AT ITS BEST

AMD's ATI Radeon Runs into Trouble

2008-10-31T17:17:00.000-07:00

It's just been a few days of lau It's just been a few days of launch and AMD's ATI Radeon HD 4830 GPU has run into problems. Apparently, some units of the graphics card sent out by their partner, HIS was adjusted to run with a pre-production version of BIOS. Older BIOS meant that the streaming processors were disabled to 560 instead of specified 640 which restricted the full potential of the card.

However, the good news is that AMD has identified the issue and claims that around 400 units of HIS boards are affected by this problem which can be easily resolved by a BIOS update.

Through consultations with AMD board partners, it has been determined with a high degree of certainty that fewer than 400 ATI Radeon HD 4830 boards from one AMD board partner, HIS, have reached the market with the pre-production BIOS incorrectly provided by AMD. As only a small number of HIS-branded ATI Radeon HD 4830 cards are impacted, we ask any customers that purchased an HIS-branded ATI Radeon HD 4830 to test the board using the GPU-Z utility (available at Techpowerup.com ). If the GPU-Z utility reports fewer than 640 shaders, please visit the HIS website for information on how to update the card BIOS via a downloadable install utility."

Nokia XpressMusic 5320

2008-10-31T17:10:00.000-07:00

The XpressMusic Series of phones from Nokia got hotter with the release of the Tube now christened the XpressMusic 5800. However, we still don't have it with us as it's yet to hit the Indian market sometime in this month. Today we look at one of the smartest XpressMusic phones I've come across after a really long time - XpressMuic 5320.

I was not too impressed with the looks of the XpressMusic 5320, but I'll leave that for the end-user to decide.

The phone though does have an appeal by the kind of convergence it offers, which is exactly what helps this phone grow onto anyone who uses it. Being one in the intermediate range of handsets, it will create quite a stir in the sales of Nokia phones.

Bundle

Nokia XpressMusic 5320

Stereo Headset (3.5mm jack)

512 MB microSD card

USB Data Cable

Software & Manual

Specifications

XpressMusic

The 5320 XpressMusic phone has some added features as compared to the other phones in the XpressMusic series. Apart from the whole application bundle, there are two other factors that give the 5320 the edge in the series, even though it just an intermediate phone - Say & Play and N-Gage. So a quick word on its specialties.

Say & Play

The Say and Play XpressMusic feature is quite unique, one that I haven't seen in any other phone before. Say and Play works with you telling the phone which song to play and it plays it, much like a voice command. A recording begins once you keep the Own key pressed. You then have to mention the artist name and song, and you will be provided with a list of songs under his/her name.

You can further narrow it right down to just one song or album by adding the name of the album or song after the artist name. Just the name of the song or the artist won't do. Soon hopefully it will even recognize song names and take just that for a 'Say and Play' command.

N-Gage

The 5320 XpressMusic phone also supports the N-Gage platform. With an 8-way navigational D-Pad and gaming keys the phone is all ready to game. However, with the kind of games that are being designed for phones, it requires more than just the keys and the support.

It needs the power and very frankly the 5320 is very capable of it. I tried a couple of games and they ran smooth just like the phone houses a 3D Hardware accelerator. Though no mention of it has been made and I won't be surprised if it did.

It's not a very expensive device, at around €220 (£180 / $360) before tax and subsidy. And to a certain extent you can tell that there have been a few trade-offs when it comes to design. The QVGA resolution display is 2" in size, the camera has a flash but no autofocus and talktime is just 2.5 hours on 3G. Video capture is 320 x 240 pixels at 15 fps. It's certainly not as good as an N-Series device.. but then it is a lot cheaper.

The Nokia 5320 XpressMusic phone sells for around Rs.10,000 with a 1-year warranty. The phone may not be one of the most appealing to the eye but it sure has quite a good number of tricks under its sleeve.
You have to use the handset to know what it is capable of. The 5320 XpressMusic is mainly a music centric device, though it's capable of more.

The only competition I see from the Walkman is the W580i and given an option I would go in for the XpressMuisc 5320 for its features. But if its music quality, nothing beats the in-earplugs offered default in the package of the W580i. Maybe a 1GB card in the 5320's package could turn the tables on the W580i.

Sony Ericsson XPERIA X1

2008-10-31T17:06:00.000-07:00

The XPERIA runs on the Windows Mobile OS - v6.1 and it runs smooth and being a Windows Mobile OS it's not something tough to get used to. If you remember I did mention in the HTC Touch Diamond review that the phone has opened this whole new avenue for Windows Mobile Devices. Well that's what it is exactly with the XPERIA.

However, there were few things that I didn't quite like. I had earlier mentioned the call hang button held down locking the phone. I prefer to have the list of options like in the HTC Touch Diamond. So I can choose to Lock the Phone or go to Communication Manager or Enter Flight Mode etc. I hope to see it implemented in the final release.

As enjoyable it was typing on the XPERIA's QWERTY keypad I would have wanted a touch pad because the phone is pretty responsive and it does have a screen that can fit on it easily and would eliminate the need to use a stylus.

The XPERIA's 3.2 MP camera is an autofocus module assisted with flash. The camera is just a 3.2MP, which is the disappointing bit, but has enough options to keep you fiddling around. Its options are much like the G900. The camera quality is not one that I can give an opinion on because it's a prototype, but the images were pretty good.
The music player of the phone is another thing that was disappointing.

It was so basic that other than the look of it I couldn't believe it was a Sony Ericsson. So much so that it's not possible to believe that the makers of the Walkman could come up with something so bland. I hope there are more options in the Media player. The screen resolution (800 x 480 pixels) of the phone is such that it makes it good for watching widescreen movies. However, there is no support for DivX or XviD and I don't see it happening for even the final version. Hope the X2 supports all formats.

The highly-anticipated Sony Ericsson Xperia X1 smartphone has been approved by the FCC and helpfully posted on their website so I can spend my Saturday mornings combing through confusingly bureaucratic PDF files looking for announcements like this. The specific model vetted by the fatcats in Washington probably isn't the one we'll be seeing here in North America: it's referred to as the X1i, which in Sony terms means Europe, and it's not yet equipped with 3G. Still, this is a good indication that we will be getting the X1 before 2009, though it'll still be after those shifty Europeans.

The Sony Ericsson XPERIA X1 is not yet available in the Indian market and will be here only in early November. The expected price tag for the phone is anywhere between 35K - 40K, which is quite steep. I feel it's better to look at it as any other premium Sony Ericsson phone, which when launched is highly priced and later on sees a price drop.

The HTC Touch Diamond is slow and sells for a much lesser price. We will also see the Touch Pro, which should be faster and has perfect competition with the Sony Ericsson XPERIA X1. Also, the X2 is expected to feature early next year, which may demand the price of the X1 to drop. But until then it's a long wait.

Samsung I900 omnia

2008-10-31T17:03:00.000-07:00

This phone features Windows Mobile 6.1 Professional as its base operating system with the TouchWiz Interface working as a face.

It's been over a month since I reviewed the Samsung TouchWiz F480 and the more I used the phone I realized that the full touch interface from Samsung was worthy of appreciation. Now we've got our hands on the Olympiad i900 from Samsung, better known as the Omnia.

This phone features Windows Mobile 6.1 Professional as its base operating system with the TouchWiz Interface working as a face. Let's see if the Windows Mobile platform can help the TouchWiz interface get any better than the Original TouchWiz phone - the F480.

Bundle

Samsung i900 Omnia (8GB)

Stereo Headset

1GB microSD card

USB Cable

Charger

This is what we received along with the Samsung Omnia handset as its bundle.

Specification

The Samsung Omnia sells for Rs.33,500 with a 1-year warranty. After seeing the price of the TouchWiz F480, a non Windows Mobile device from Samsung for under 20K, this pricing seems rather steep. The phone does have a lot to offer with regard to its functionality.

But as I see it, the use of Windows Mobile is what has increased its price. At this price you get a lot of phones and the choice is not limited. Almost every other phone is accessible, the N95 8GB a great phone for 24K is also available but it doesn't feature DivX/XviD support.

Nevertheless, if you want DivX/XviD support you can get it by just paying a little extra for decent software. Then there is the Viewty for under 20K, however, that too misses out on Wi-Fi and its interface isn't the best. Now these options can be attained for well under the price that the Omnia is selling for.

So the question is whether you can sacrifice one of the features these phones have to offer. If you can't, then the Omnia should be able to satisfy your needs. However, if you want to save some money then it's better to go with something much cheaper than the Omnia, depending on what you want from your phone.

1,00,000 Sony Laptop Batteries Recalled

2008-10-31T17:01:00.000-07:00

You've been using Sony batteries in your HP, Dell and Toshiba notebooks.

Sony's battery woes don't seem to end. The U.S. Consumer Product Safety Commission has issued a voluntary recall of Sony batteries sold via laptop manufacturers like HP, Dell, and Toshiba.

The recall was issued after a few reported incidents where the lithium-ion batteries overheated and caught a small fire resulting in minor property damage and injuring two people with minor burns.

There are around a 35,000 affected batteries sold in the US through HP, Dell and Toshiba, while the remaining 65,000 have been sold worldwide as separate battery packs. Sony has acknowledged the battery recall and issued a statement for the same.

"It is believed that most of these incidents were related to manufacturing line adjustments made from October 2004 to June 2005, which may have affected some battery cells produced during that period. In addition, there were some incidents that may have involved a raw material flaw."

India get hands on Nokia N79

2008-10-31T16:58:00.000-07:00

As promised, Nokia has started shipping its N79 for the Indian market. The phone was unveiled in August this year.

The N79 is aimed at the style-conscious multimedia phone users. For the same, the phone comes with a range of features that include integrated navigation, music with FM transmitter, high-speed connectivity capability, Web browsing, 10 pre-loaded N-Gage games.

For the style-factor, the phone will be bundled with three 'Xpress-On' swappable smart covers -- available in 5 colors: Light Sea Blue, Espresso Brown, Olive Green, White, and Coral Red.

The N79 is a candybar phone sporting a 2.4-inch screen with a resolution of 320 x 240 pixels (QVGA). It measures 110 x 49 x 15 mm and weighs 95g. Like the others in the Nseries, this phone too is powered by the Symbian operating system (OS 9.3, Series 60 v3.2) and also features a 5-megapixel camera with a Carl Zeiss autofocus lens.

The phone is 3.5G (GPRS, EDGE, HSDPA, WCDMA) ready and can also keep you connected through Wi-fi. It also bundles a Micro-USB connector (USB 2.0) for data transfer and a 3.5 mm AV connector.

Nokia N79 comes preloaded with 'Anthems 1998-2008', a compilation of 19 all-time favorite classic club songs, and 17 new age music videos (by the Ministry of Sound).

The phone also bundles along a 4GB microSD memory card to fill the void of the paltry 50 MB internal memory.

The company claims that the N79 offers up to 372 hours of battery time in standby, and 5 and a half hours while talking.

The Nokia N79 is available for an approximate price of Rs. 23, 000.

Dell launched new subnotebook: Inspiron Mini 12

2008-10-31T16:51:00.000-07:00

On Sunday, the Dell Inspiron Mini 12, a larger version of the Mini 9, makes its debut—in Japan. Dell had reached an exclusive agreement with VIC Camera, Kojima, and SofMap—all Japanese retailers—to make the early announcement overseas. According to Dell, the Inspiron 12 will ship in the United States by mid-November. The Mini 12 is officially the first netbook to house a 12-inch wide screen; the largest so far have been 10-inch models such as the Lenovo IdeaPad S10 and the MSI Wind. The screen offers 1,280-by-800 resolution, higher than the typical 1,280-by-600 netbooks. Its shape is like a wedge, measuring 9.0-by-11.8-by-0.92 inches, becoming thicker towards the back. The weight starts at 2.7 pounds, with a 3-cell battery. A 6-cell battery will be available later on and will likely bring the weight over 3 pounds.

Like the S10 and the Wind, the Mini 12’s feature set includes three USB ports, a multi card reader, Ethernet, VGA-Out, and a 1.3-mega pixel camera. Hard drives aren’t the meager solid state ones offered on the Mini 9; you have a choice of 40GB, 60GB, and 80GB spinning drives. Although it doesn’t have the antenna infrastructure to support WWAN, an empty slot is available for it, like on the Mini 9. In the meantime, the Mini 12 has both Wi-Fi and Bluetooth built in. Like the Mini 9, the new Mini uses Intel’s Atom platform: The 1.33-GHz Z520 and the 1.6-GHz Z530 Atom processor are both available come November. The Mini 12 is one of the few systems to run Windows Vista Basic, which will be the only choice for operating systems at this time. The Vista system starts at $550.

Source: Computer World

Future of Mobile - Google Android Phone

2008-10-31T16:45:00.000-07:00

The main event of the night, was Google’s presenter Justin Baird on the future of mobile. He started off by presenting some interesting stats such as there being 1.3Billion people having internet access versus 3.3Billion having mobile phones. Obviously, mobile presents a wealth of untapped opportunites. there are more people sending SMS than using search engines. Everyone in the developed world has a mobile - if not one, than two!

Justin talked about a bunch of other stuff, but the only stuff which I remember was what we had all been waiting for - The Andriod - Google’s answer to the Apple Iphone. A very cool device I must say. Again, this bordered on being a product pitch, but that’s what happens when you attend a marketing event.

The Android is really different to any other phone because it an open source product, which I found rather interesting. The Apple Iphone or any other phone, is a static device because you only use the applications already found on your mobile i.e. they have already been preprogrammed on there. Being capable of open source, means that new developments and applications can be constantly added. Google is adopting a similar practice to its igoogle portal which has open source for its applications. I’ve got a igoogle portal, and I’m fascinated by the amount of widgets they have developed for it. You name it, and they’ve got it. If they dont have it, you can develop it, if you have the necessary know how. That is one of the reasons facebook is so popular, because new apps are constantly being developed by the user community.

I think we will see a lot more mashup apps involving google maps. What the phone does is triangulate your position using cell towers, giving you a fairly good idea of where you are. The thing that really blew me away was compass function using google maps. Imagine having a screen showing you where you want to go. When you move, the phone acts like a compass and adjusts the picture based on where you have moved, giving you a real picture. Very cool.

In addition, because Google is behind it, you know that search has to be incorporated somehow. the stats really surprised me. The click through rate for display ads on google typically is 0.2%. However, on mobiles, that rate is 2%. That’s a 10 fold increase. I tell you why - because the ads become even more relevant based on your location. If your current location is say Parramatta, and you search for restaurants and ads come up for that area, you are more inclined to click on those ads on your mobile. With the unleashing of True Local, we will really see the power of geographic based ads.

From the presentation and my own experience overseas, Australia is really behind globally in the mobile experience. But we are catching up. I remember friends of mine in New York, using blackberries to search for places using google maps. In the U.S they also have unlimited data ability for their phones. Phone data charges here are quite prohibitive - the carriers have to work together to find a way to somehow get to the level of unlimited data downloads. But its probably not going to happen because we can’t get enough people onto the network to make that feasible.

After this presentation, I really do think there are lot more marketing and innovative opportunites we can use with mobiles. I mean more people have mobiles than computers. A mobile is our social currency and keeps us attuned with our friends and family. It is only natural that it becomes even more extended into our lives. Once we can get full internet functionability on our phones, we will really see the true power of mobiles. And there really won’t be a distinction between online and offline. We’ll always be connected.

Android phone already vulnerable to attacks

2008-10-31T16:40:00.000-07:00

Less than a week after the release of Google’s T-Mobile G1 smart phone, security experts detected a serious security flaw in its Android operating system that leaves it wide open for hackers to launch drive-by attacks on users’ devices.The security vulnerability, detected by researchers at Baltimore, Maryland-based Independent Security Evaluators, follows last week’s release of Google’s T-Mobile G1 phone Oct. 22, which is powered by the Android operating system.

“These phones will currently ship with the vulnerability present and may pose a security risk to their users until and update becomes available,” said Miller in his posting. According to the advisory, Google Android relies on more than 80 different open source packages. And the security error stems from a buffer overflow vulnerability in some of the older, more vulnerable versions of the open source software. Subsequently, an unsuspecting user could be successfully exploited simply by accessing an infected Web page using with a vulnerable operating system, experts say. Once a user in infected, attackers could then obtain access to any personal information accessible from the victim’s browser — including cookies, information entered into Web application and saved passwords — in order to steal a bank account numbers, Social Security information and other sensitive data.

Source: CRN

Robotic Surgeons

2008-05-15T12:29:00.000-07:00

The first generation of surgical robots are already being installed in a number of operating rooms around the world. These aren't true autonomous robots that can perform surgical tasks on their own, but they are lending a mechanical helping hand to surgeons. These machines still require a human surgeon to operate them and input instructions. Remote control and voice activation are the methods by which these surgical robots are controlled.

Types of instruments used
by the da Vinci Surgical System

Robotics are being introduced to medicine because they allow for unprecedented control and precision of surgical instruments in minimally invasive procedures. So far, these machines have been used to position an endoscope, perform gallbladder surgery and correct gastroesophogeal reflux and heartburn. The ultimate goal of the robotic surgery field is to design a robot that can be used to perform closed-chest, beating-heart surgery. According to one manufacturer, robotic devices could be used in more than 3.5 million medical procedures per year in the United States alone. Here are three surgical robots that have been recently developed:

da Vinci Surgical System
ZEUS Robotic Surgical System
AESOP Robotic System

On July 11, 2000, the U.S. Food and Drug Administration (FDA) approved the da Vinci Surgical System, making it the first robotic system allowed to be used in American operating rooms. Developed by Intuitive Surgical, da Vinci uses technology that allows the human surgeon to get closer to the surgical site than human vision will allow, and work at a smaller scale than conventional surgery permits. The $1 million da Vinci system consists of two primary components:

A viewing and control console
A surgical arm unit

In using da Vinci for gallbladder surgery, three incisions -- no larger than the diameter of a pencil -- are made in the patient's abdomen, which allows for three stainless-steel rods to be inserted. The rods are held in place by three robotic arms. One of the rods is equipped with a camera, while the other two are fitted with surgical instruments that are able to dissect and suture the tissue of the gallbladder. Unlike in conventional surgery, these instruments are not directly touched by the doctor's hands.

Photo courtesy Intuitive Surgical.
Surgeon's view when using the da Vinci Surgical System

Sitting at the control console, a few feet from the operating table, the surgeon looks into a viewfinder to examine the 3-D images being sent by the camera inside the patient. The images show the surgical site and the two surgical instruments mounted on the tips of two of the rods. Joystick-like controls, located just underneath the screen, are used by the surgeon to manipulate the surgical instruments. Each time one of the joysticks is moved, a computer sends an electronic signal to one of the instruments, which moves in sync with the movements of the surgeon's hands.

Another robotic system that is close to being cleared by the FDA is the ZEUS System, made by Computer Motion, which is already available in Europe. However, both the da Vinci and ZEUS systems must receive governmental approval for each procedure that a surgeon plans to use it for. The $750,000 ZEUS has a similar setup to that of the da Vinci. It has a computer workstation, a video display, and hand controls that are used to move the table-mounted surgical instruments. While the ZEUS system has not yet been cleared for American use beyond clinical trials, German doctors have already used the system to perform coronary bypass surgery.

The ZEUS system employs the assistance of the Automated Endoscopic System for Optimal Positioning (AESOP) Robotic System. Released by Computer Motion in 1994, AESOP was the first robot to be cleared by the FDA for assisting surgery in the operating room. AESOP is much simpler than the da Vinci and ZEUS systems. It's basically just one mechanical arm, used by the physician to position the endoscope -- a surgical camera inserted into the patient. Foot pedals or voice-activated software allow the physician to position the camera, leaving his or her hands free to continue operating on the patient.

Robots and Artificial Intelligence

2008-05-15T12:27:00.000-07:00

Artificial intelligence (AI) is arguably the most exciting field in robotics. It's certainly the most controversial: Everybody agrees that a robot can work in an assembly line, but there's no consensus on whether a robot can ever be intelligent.

AI in the Movies

2001: A Space Odyssey

Bicentennial Man

Blade Runner

Demon Seed

The Matrix

Short Circuit

The Terminator

Westworld

Like the term "robot" itself, artificial intelligence is hard to define. Ultimate AI would be a recreation of the human thought process -- a man-made machine with our intellectual abilities. This would include the ability to learn just about anything, the ability to reason, the ability to use language and the ability to formulate original ideas. Roboticists are nowhere near achieving this level of artificial intelligence, but they have had made a lot of progress with more limited AI. Today's AI machines can replicate some specific elements of intellectual ability.

Computers can already solve problems in limited realms. The basic idea of AI problem-solving is very simple, though its execution is complicated. First, the AI robot or computer gathers facts about a situation through sensors or human input. The computer compares this information to stored data and decides what the information signifies. The computer runs through various possible actions and predicts which action will be most successful based on the collected information. Of course, the computer can only solve problems it's programmed to solve -- it doesn't have any generalized analytical ability. Chess computers are one example of this sort of machine.

Some modern robots also have the ability to learn in a limited capacity. Learning robots recognize if a certain action (moving its legs in a certain way, for instance) achieved a desired result (navigating an obstacle). The robot stores this information and attempts the successful action the next time it encounters the same situation. Again, modern computers can only do this in very limited situations. They can't absorb any sort of information like a human can. Some robots can learn by mimicking human actions. In Japan, roboticists have taught a robot to dance by demonstrating the moves themselves.

Some robots can interact socially. Kismet, a robot at M.I.T's Artificial Intelligence Lab, recognizes human body language and voice inflection and responds appropriately. Kismet's creators are interested in how humans and babies interact, based only on tone of speech and visual cue. This low-level interaction could be the foundation of a human-like learning system.

Kismet and other humanoid robots at the M.I.T. AI Lab operate using an unconventional control structure. Instead of directing every action using a central computer, the robots control lower-level actions with lower-level computers. The program's director, Rodney Brooks, believes this is a more accurate model of human intelligence. We do most things automatically; we don't decide to do them at the highest level of consciousness.

Photo courtesy Kitano Symbiotic Systems Project
Kitano's PINO
"The Humanoid Robot"

works. Developing AI isn't like building an artificial heart -- scientists don't have a simple, concrete model to work from. We do know that the The real challenge of AI is to understand how natural intelligencebrain contains billions and billions of neurons, and that we think and learn by establishing electrical connections between different neurons. But we don't know exactly how all of these connections add up to higher reasoning, or even low-level operations. The complex circuitry seems incomprehensible.

Because of this, AI research is largely theoretical. Scientists hypothesize on how and why we learn and think, and they experiment with their ideas using robots. Brooks and his team focus on humanoid robots because they feel that being able to experience the world like a human is essential to developing human-like intelligence. It also makes it easier for people to interact with the robots, which potentially makes it easier for the robot to learn.

Just as physical robotic design is a handy tool for understanding animal and human anatomy, AI research is useful for understanding how natural intelligence works. For some roboticists, this insight is the ultimate goal of designing robots. Others envision a world where we live side by side with intelligent machines and use a variety of lesser robots for manual labor, health care and communication. A number of robotics experts predict that robotic evolution will ultimately turn us into cyborgs -- humans integrated with machines. Conceivably, people in the future could load their minds into a sturdy robot and live for thousands of years!

In any case, robots will certainly play a larger role in our daily lives in the future. In the coming decades, robots will gradually move out of the industrial and scientific worlds and into daily life, in the same way that computers spread to the home in the 1980s.

The best way to understand robots is to look at specific designs. The links on the next page will show you a variety of robot projects around the world.

Homebrew Robots

2008-05-15T12:25:00.001-07:00

In the last couple of sections, we looked at the most prominent fields in the world of robots -- industry robotics and research robotics. Professionals in these fields have made most of the major advancements in robotics over the years, but they aren't the only ones making robots. For decades, a small but passionate band of hobbyists has been creating robots in garages and basements all over the world.

Homebrew robotics is a rapidly expanding subculture with a sizable Web presence. Amateur roboticists cobble together their creations using commercial robot kits, mail order components, toys and even old VCRs.

Homebrew robots are as varied as professional robots. Some weekend roboticists tinker with elaborate walking machines, some design their own service bots and others create competitive robots. The most familiar competitive robots are remote control fighters like you might see on "BattleBots." These machines aren't considered "true robots" because they don't have reprogrammable computer brains. They're basically souped-up remote control cars.

More advanced competitive robots are controlled by computer. Soccer robots, for example, play miniaturized soccer with no human input at all. A standard soccer bot team includes several individual robots that communicate with a central computer. The computer "sees" the entire soccer field with a video camera and picks out its own team members, the opponent's members, the ball and the goal based on their color. The computer processes this information at every second and decides how to direct its own team.

Check out the official RoboCup Web site for more information on Soccer robots, and Google > Computers > Robotics > Competitions for information on other robot competitions. Google > Computers > Robotics > Building will give you more information on building your own robots.

Adaptable and Universal
The personal computer revolution has been marked by extraordinary adaptability. Standardized hardware and programming languages let computer engineers and amateur programmers mold computers to their own particular purposes. Computer components are sort of like art supplies -- they have an infinite number of uses.

Most robots to date have been more like kitchen appliances. Roboticists build them from the ground up for a fairly specific purpose. They don't adapt well to radically new applications.

This situation may be changing. A company called Evolution Robotics is pioneering the world of adaptable robotics hardware and software. The company hopes to carve out a niche for itself with easy-to-use "robot developer kits."

The kits come with an open software platform tailored to a range of common robotic functions. For example, roboticists can easily give their creations the ability to follow a target, listen to voice commands and maneuver around obstacles. None of these capabilities are revolutionary from a technology standpoint, but it's unusual that you would find them in one simple package.

The kits also come with common robotics hardware that connects easily with the software. The standard kit comes with infrared sensors, motors, a microphone and a video camera. Roboticists put all these pieces together with a souped-up erector set -- a collection of aluminum body pieces and sturdy wheels.

These kits aren't your run-of-the-mill construction sets, of course. At upwards of $700, they're not cheap toys. But they are a big step toward a new sort of robotics. In the near future, creating a new robot to clean your house or take care of your pets while you're away might be as simple as writing a BASIC program to balance your checkbook.

Autonomous Robots

2008-05-15T12:24:00.002-07:00

Autonomous robots can act on their own, independent of any controller. The basic idea is to program the robot to respond a certain way to outside stimuli. The very simple bump-and-go robot is a good illustration of how this works.

This sort of robot has a bumper sensor to detect obstacles. When you turn the robot on, it zips along in a straight line. When it finally hits an obstacle, the impact pushes in its bumper sensor. The robot's programming tells it to back up, turn to the right and move forward again, in response to every bump. In this way, the robot changes direction any time it encounters an obstacle.

Photo courtesy NASA
The autonomous Urbie is designed for various urban operations, including military reconnaissance
and rescue operations.

Advanced robots use more elaborate versions of this same idea. Roboticists create new programs and sensor systems to make robots smarter and more perceptive. Today, robots can effectively navigate a variety of environments.

Simpler mobile robots use infrared or ultrasound sensors to see obstacles. These sensors work the same way as animal echolocation: The robot sends out a sound signal or a beam of infrared light and detects the signal's reflection. The robot locates the distance to obstacles based on how long it takes the signal to bounce back.

Urbie's view

More advanced robots use stereo vision to see the world around them. Two cameras give these robots depth perception, and image-recognition software gives them the ability to locate and classify various objects. Robots might also use microphones and smell sensors to analyze the world around them.

Some autonomous robots can only work in a familiar, constrained environment. Lawn-mowing robots, for example, depend on buried border markers to define the limits of their yard. An office-cleaning robot might need a map of the building in order to maneuver from point to point.

More advanced robots can analyze and adapt to unfamiliar environments, even to areas with rough terrain. These robots may associate certain terrain patterns with certain actions. A rover robot, for example, might construct a map of the land in front of it based on its visual sensors. If the map shows a very bumpy terrain pattern, the robot knows to travel another way. This sort of system is very useful for exploratory robots that operate on other planets (check out JPL Robotics to learn more).

An alternative robot design takes a less structured approach -- randomness. When this type of robot gets stuck, it moves its appendages every which way until something works. Force sensors work very closely with the actuators, instead of the computer directing everything based on a program. This is something like an ant trying to get over an obstacle -- it doesn't seem to make a decision when it needs to get over an obstacle, it just keeps trying things until it gets over it.

Mobile Robots

2008-05-15T12:24:00.001-07:00

Robotic arms are relatively easy to build and program because they only operate within a confined area. Things get a bit trickier when you send a robot out into the world.

Photo courtesy NASA
NASA's FIDO Rover is designed for exploration on Mars.

The first obstacle is to give the robot a working locomotion system. If the robot will only need to move over smooth ground, wheels or tracks are the best option. Wheels and tracks can also work on rougher terrain if they are big enough. But robot designers often look to legs instead, because they are more adaptable. Building legged robots also helps researchers understand natural locomotion -- it's a useful exercise in biological research.

Photo courtesy Fujitsu and K&D Technology, Inc.
Fujitsu's HOAP-1 robot

Typically, hydraulic or pneumatic pistons move robot legs back and forth. The pistons attach to different leg segments just like muscles attach to different bones. It's a real trick getting all these pistons to work together properly. As a baby, your brain had to figure out exactly the right combination of muscle contractions to walk upright without falling over. Similarly, a robot designer has to figure out the right combination of piston movements involved in walking and program this information into the robot's computer. Many mobile robots have a built-in balance system (a collection of gyroscopes, for example) that tells the computer when it needs to correct its movements.

Photo courtesy NASA
NASA's Frogbot uses springs, linkages and motors to hop from place to place.

Bipedal locomotion (walking on two legs) is inherently unstable, which makes it very difficult to implement in robots. To create more stable robot walkers, designers commonly look to the animal world, specifically insects. Six-legged insects have exceptionally good balance, and they adapt well to a wide variety of terrain.

Some mobile robots are controlled by remote -- a human tells them what to do and when to do it. The remote control might communicate with the robot through an attached wire, or using radio or infrared signals. Remote robots, often called puppet robots, are useful for exploring dangerous or inaccessible environments, such as the deep sea or inside a volcano. Some robots are only partially controlled by remote. For example, the operator might direct the robot to go to a certain spot, but not steer it there -- the robot would find its own way.

The Robotic Arm

2008-05-15T12:23:00.001-07:00

The term robot comes from the Czech word robota, generally translated as "forced labor." This describes the majority of robots fairly well. Most robots in the world are designed for heavy, repetitive manufacturing work. They handle tasks that are difficult, dangerous or boring to human beings.

Robotic arms are an essential part of car manufacturing.

The most common manufacturing robot is the robotic arm. A typical robotic arm is made up of seven metal segments, joined by six joints. The computer controls the robot by rotating individual step motors connected to each joint (some larger arms use hydraulics or pneumatics). Unlike ordinary motors, step motors move in exact increments (check out Anaheim Automation to find out how). This allows the computer to move the arm very precisely, repeating exactly the same movement over and over again. The robot uses motion sensors to make sure it moves just the right amount.

An industrial robot with six joints closely resembles a human arm -- it has the equivalent of a shoulder, an elbow and a wrist. Typically, the shoulder is mounted to a stationary base structure rather than to a movable body. This type of robot has six degrees of freedom, meaning it can pivot in six different ways. A human arm, by comparison, has seven degrees of freedom.

Your arm's job is to move your hand from place to place. Similarly, the robotic arm's job is to move an end effector from place to place. You can outfit robotic arms with all sorts of end effectors, which are suited to a particular application. One common end effector is a simplified version of the hand, which can grasp and carry different objects. Robotic hands often have built-in pressure sensors that tell the computer how hard the robot is gripping a particular object. This keeps the robot from dropping or breaking whatever it's carrying. Other end effectors include blowtorches, drills and spray painters.

Industrial robots are designed to do exactly the same thing, in a controlled environment, over and over again. For example, a robot might twist the caps onto peanut butter jars coming down an assembly line. To teach a robot how to do its job, the programmer guides the arm through the motions using a handheld controller. The robot stores the exact sequence of movements in its memory, and does it again and again every time a new unit comes down the assembly line.

Most industrial robots work in auto assembly lines, putting cars together. Robots can do a lot of this work more efficiently than human beings because they are so precise. They always drill in the exactly the same place, and they always tighten bolts with the same amount of force, no matter how many hours they've been working. Manufacturing robots are also very important in the computer industry. It takes an incredibly precise hand to put together a tiny microchip.

Robot Basics

2008-05-15T12:21:00.000-07:00

The vast majority of robots do have several qualities in common. First of all, almost all robots have a movable body. Some only have motorized wheels, and others have dozens of movable segments, typically made of metal or plastic. Like the bones in your body, the individual segments are connected together with joints.

Photo courtesy NASA
A robotic hand, developed by NASA, is made up of metal segments moved by tiny motors. The hand is one of the most difficult structures to replicate in robotics.

Robots spin wheels and pivot jointed segments with some sort of actuator. Some robots use electric motors and solenoids as actuators; some use a hydraulic system; and some use a pneumatic system (a system driven by compressed gases). Robots may use all these actuator types.

A robot needs a power source to drive these actuators. Most robots either have a battery or they plug into the wall. Hydraulic robots also need a pump to pressurize the hydraulic fluid, and pneumatic robots need an air compressor or compressed air tanks.

The actuators are all wired to an electrical circuit. The circuit powers electrical motors and solenoids directly, and it activates the hydraulic system by manipulating electrical valves. The valves determine the pressurized fluid's path through the machine. To move a hydraulic leg, for example, the robot's controller would open the valve leading from the fluid pump to a piston cylinder attached to that leg. The pressurized fluid would extend the piston, swiveling the leg forward. Typically, in order to move their segments in two directions, robots use pistons that can push both ways.

The robot's computer controls everything attached to the circuit. To move the robot, the computer switches on all the necessary motors and valves. Most robots are reprogrammable -- to change the robot's behavior, you simply write a new program to its computer.

Photo courtesy NASA JPL
NASA's Urbie climbing stairs

Not all robots have sensory systems, and few have the ability to see, hear, smell or taste. The most common robotic sense is the sense of movement -- the robot's ability to monitor its own motion. A standard design uses slotted wheels attached to the robot's joints. An LED on one side of the wheel shines a beam of light through the slots to a light sensor on the other side of the wheel. When the robot moves a particular joint, the slotted wheel turns. The slots break the light beam as the wheel spins. The light sensor reads the pattern of the flashing light and transmits the data to the computer. The computer can tell exactly how far the joint has swiveled based on this pattern. This is the same basic system used in computer mice.

These are the basic nuts and bolts of robotics. Roboticists can combine these elements in an infinite number of ways to create robots of unlimited complexity. In the next section, we'll look at one of the most popular designs, the robotic arm.

How Robots Work

2008-05-15T12:16:00.000-07:00

On the most basic level, human beings are made up of five major components:

A body structure
A muscle system to move the body structure
A sensory system that receives information about the body and the surrounding environment
A power source to activate the muscles and sensors
A brain system that processes sensory information and tells the muscles what to do

Of course, we also have some intangible attributes, such as intelligence and morality, but on the sheer physical level, the list above about covers it.

A robot is made up of the very same components. A typical robot has a movable physical structure, a motor of some sort, a sensor system, a power supply and a computer "brain" that controls all of these elements. Essentially, robots are man-made versions of animal life -- they are machines that replicate human and animal behavior.

In this article, we'll explore the basic concept of robotics and find out how robots do what they do.

Robot Image Gallery

Photo courtesy NASA Jet Propulsion Laboratory
NASA's Urban Robot, Urbie, features software-controlled cameras and sensors that allow it to operate autonomously in many types of terrain. URBIE checks out areas that would pose potential risks to human investigators.

Joseph Engelberger, a pioneer in industrial robotics, once remarked "I can't define a robot, but I know one when I see one." If you consider all the different machines people call robots, you can see that it's nearly impossible to come up with a comprehensive definition. Everybody has a different idea of what constitutes a robot.

You've probably heard of several of these famous robots:

R2D2 and C-3PO: The intelligent, speaking robots with loads of personality in the "Star Wars" movies
Sony's AIBO: A robotic dog that learns through human interaction
Honda's ASIMO: A robot that can walk on two legs like a person
Industrial robots: Automated machines that work on assembly lines
Data: The almost human android from "Star Trek"
BattleBots: The remote control fighters on Comedy Central
Bomb-defusing robots
NASA's Mars rovers
HAL: The ship's computer in Stanley Kubrick's "2001: A Space Odyssey"
Robomower: The lawn-mowing robot from Friendly Robotics
The Robot in the television series "Lost in Space"
MindStorms: LEGO's popular robotics kit

HowStuffWorks has several articles on other types of robots:

How Robotic Surgery Will Work
How Robonauts Will Work
How Snakebots Will Work
How Rumble Robots Work
How Stinger Missiles Work

All of these things are considered robots, at least by some people. The broadest definition around defines a robot as anything that a lot of people recognize as a robot. Most roboticists (people who build robots) use a more precise definition. They specify that robots have a reprogrammable brain (a computer) that moves a body.

By this definition, robots are distinct from other movable machines, such as cars, because of their computer element. Many new cars do have an onboard computer, but it's only there to make small adjustments. You control most elements in the car directly by way of various mechanical devices. Robots are distinct from ordinary computers in their physical nature -- normal computers don't have a physical body attached to them.

Web Conferencing Features

2008-03-13T11:52:00.001-07:00

Web conferencing programs come with a tremendous variety of features and capabilities. Some can merge with a company's existing e-mail, calendar, messaging and office productivity applications. Some allow attendees to view the presentation in their regular web browser without installing any additional software.

Depending on the software, people can:

View slide presentations from programs like PowerPoint
Draw or write on a common whiteboard by using their computer mice or typing
Annotate images and diagrams using the same whiteboard principle
Transmit still pictures or video to other attendees via a webcam (This increases the required bandwidth and can sometimes slow the transfer of the presentation.)
View information from the moderator's computer desktop using screen sharing
Share documents, often even if attendees don't have the software that created them, using application sharing
Hold interactive question-and-answer sessions that integrate video and audio
Send public or private messages through instant messaging
Annotate or modify documents and spreadsheets from compatible applications
Transfer files between attendees
Ask and answer questions through audio chat (as an integrated part of the software) or by phone

Some web conferencing programs
can replicate real-world whiteboards.

Since these meetings take place over the Internet, programs include options for security and encryption. Most programs require moderators and attendees to use a login name and password to access the meeting. Some use SSL or TLS encryption to protect data. Some companies also host web conferences on internal servers so that the data stays behind the corporate firewall. The moderator or host can monitor who is participating in the conference through sign-in logs and roll calls.

A Typical Online Meeting
Web conferences can vary dramatically depending on software, hosting and how the moderator runs the meeting. Here are the basic steps used with many meeting programs:

The moderator gathers content for the meeting, including spreadsheets, documents and presentations from other applications.
The moderator sets a time and date for the meeting and uses the meeting software to invite attendees via e-mail.
The attendees accept the invitation, and their calendar programs add the meeting to their calendars.
The meeting moderator opens the conferencing software before the meeting is scheduled to start and makes sure the connections and content are working properly.
When the meeting time arrives, the attendees click on the URL in their invitation email to go to the meeting.
The visual portion of the meeting takes place in the meeting software or in a web browser.
The moderator and participants communicate by phone, voice chat or instant messenger during the meeting.
At the end of the meeting, the moderator and attendees close their programs or browser windows and sign off.

Teleconferencing Online

2008-03-13T11:51:00.000-07:00

Web conferencing allows people to communicate through text and video in addition to audio. The simplest web conferencing methods use chat and instant messaging programs to host text-based group discussions. More sophisticated programs exchange visual information with webcams and streaming video. Some allow people to share documents online.

Companies can either purchase conferencing software and host their meetings themselves or use a hosting service. Hosting services provide the software and server space on which to conduct meetings. Either way, the company or the hosting service must have software to coordinate the meeting and ample server space and bandwidth to accommodate it.

Web conferencing programs combine tools already common to web pages and Internet communication. They bundle these tools into one interface to create an interactive meeting environment. These tools include:

HTML, XML and ASP markup
Java scripts
Flash animation
Instant messaging
Streaming audio and video

Some programs are entirely computer- and Internet-based. Others use the telephone system to distribute audio content. To participate in the online meetings, participants must have:

A computer
An Internet connection
A telephone, if audio content is not provided online

If the conferencing program relies on Internet-based audio chat and webcam feeds, the participants' PCs should have:

Microphones
Webcams
Video capture cards

In general, every online presentation or meeting has a moderator and attendees. The moderator sets the time and date of the meeting, prepares the content and makes sure everything works properly before the meeting begins. Attendees can either view the presentation without giving feedback or can collaborate, based on the settings and capabilities of the programs. Often, moderators can record the presentation for later viewing and can pass their moderator capabilities to attendees during the meeting.

But what can people do in these virtual meeting rooms? Let's find out.

Other Uses for Web ConferencingWeb conferences aren't just for businesses. Hospitals can use audio and video conferencing to supplement their emergency room staff. For example, some Massachusetts hospitals use video conferencing to allow neurologists to confer with stroke patients. Web conferencing has also allowed deployed soldiers to communicate with their families and even get married.

How Teleconferencing Works : Introduction to How Teleconferencing Works

2008-03-13T11:50:00.000-07:00

In the past few years, corporations have gotten bigger and more spread out. Many American employees -- more than 44 million in 2004 -- also do at least some of their work from home [ref]. Since offices and employees can be thousands of miles apart, getting everyone into the same room for meetings and training has become decidedly impractical for a lot of companies.

That's why teleconferencing -- the real-time exchange of information between people who are not in the same physical space -- has become such a big industry. The American audio conferencing industry alone reported $2.25 billion in revenue in 2004 [ref]. Through teleconferencing, companies can conduct meetings, customer briefs, training, demonstrations and workshops by phone or online instead of in person.

In this article, we'll look at different types of teleconferencing, from conference calls to online meetings.

The simplest phone teleconference is a three-way call, available in many homes as a service from the telephone company. Another very simple (but not necessarily effective) method is to have two groups of people talk to one another via speakerphone. The limits of three-way calling and the sound quality of speakerphones make both of these options impractical for most businesses.

Conference calls let groups of people -- from a few to hundreds -- communicate by phone. Banks and brokerages often use conference calls to give status reports to large numbers of listeners. Other businesses use conference calls to help coworkers communicate, plan and brainstorm. To connect to the call, attendees call a designated number (MeetMe conferencing), or an operator or moderator calls each participant (ad hoc conferencing).

Conference calls connect people through a conference bridge, which is essentially a server that acts like a telephone and can answer multiple calls simultaneously. Software plays a large role in the bridge's capabilities beyond simply connecting multiple callers.

A company can have its own bridge or can contract with a service provider for conference call hosting. Providers frequently offer add-on features for conference calls, such as:

Attendee polling
Call recording
In-call operators or attendants

Companies using Voice over IP (VoIP) telephones can also host conference calls themselves if the VoIP software supports them.

Many phone conferencing systems require a login and personal identification number (PIN) to access the system. This helps protect confidential and proprietary information during the call.

Video phones can add a visual element to conference calls, but businesses often need to share other visual information.

Use of VoIP in Amateur Radio

2008-03-13T11:43:00.000-07:00

Think of amateur radio, or ham radio, as an early version of the Internet. Using a worldwide network of radio towers, antennas and transceivers, amateur radio enthusiasts are able to communicate with fellow hobbyists around the globe, sometimes by voice and sometimes by Morse code.

Amateur or ham radio operators can use VoIP technology to set up temporary stations such as this one used by the Red Cross following Sept. 11.

Amateur radio is limited by the distance that radio waves can travel. To send a signal to the other side of the world requires calculated timing and more than a little bit of luck. Every 11 years, for example, there's a peak in the number of sunspots produced by the sun, which increases the intensity of something called ionospheric propagation [source: International Solar Terrestrial Physics Program]. By bouncing radio signals high into the ionosphere, ham radio users can send long-distance messages. During off-peak years it's much more difficult.

Now amateur radio fans are using VoIP technology to link users around the globe. Here's how it works. Ham radio has always relied on FM repeaters, large radio towers that act as base stations for accessing the radio network from home. By attaching an Internet-connected PC to these repeater stations, people can communicate with the repeater using VoIP.

Several amateur radio fans have developed special software that helps connect home radio transceivers to the Internet. Users can connect their ham radio transceivers to their PC sound card and use the computer software to search for available repeater stations across the world [source: ARRL]. No longer are ham radio fans limited to the closest repeater station. If you live in Indiana, you can call into a repeater station in Mozambique and chat with local amateur radio aficionados instantly.

There are also software programs that allow you to communicate with other amateur radio users directly from your PC, without having an actual ham radio [source: ARRL]. Some ham radio purists wouldn't call this amateur radio, while others hope that this new technology will draw more young people into the hobby.

VoIP Cell Phones

2008-03-13T11:42:00.000-07:00

VoIP-enabled cell phones are just entering the consumer market. In the United States, only T-Mobile's HotSpot@Home service allows customers to make cell phone calls over a VoIP network. HotSpot@Home relies on a device called a dual-mode cell phone.

Image courtesy of T-Mobile
HotSpot@Home lets you make cell phone calls over your home WiFi network. Learn how this useful technology integrates seamlessly between two networks.

Dual-mode cell phones contain both a regular cellular radio and a Wi-Fi (802.11 b/g) radio. The Wi-Fi radio enables the cell phone to connect to a wireless Internet network through a wireless router. If you have a wireless Internet router in your home, or if you're sitting at a Starbucks with wireless Internet access, you can use your cell phone to make VoIP calls. Here's how it works:

When the cell phone is in range of a wireless Internet network, the phone automatically recognizes and connects to the network.
Any calls you initiate on the wireless network are routed through the Internet as VoIP calls. With HotSpot@Home, all VoIP calls are free.
If the phone is out of range of a wireless Internet signal, it automatically switches over to the regular cellular network and calls are charged as normal.
Dual-mode phones can hand off seamlessly from Wi-Fi to cellular (and vice versa) in the middle of a call as you enter and exit Wi-Fi networks.

Similar to dual-mode cell phones are Wi-Fi phones. Wi-Fi phones aren't technically cell phones because they only have a Wi-Fi radio, not a cellular radio. Wi-Fi phones look like cell phones (small, lightweight handsets), but can only make calls when connected to a wireless Internet network. That means all Wi-Fi phone calls are VoIP calls.

Wi-Fi phones are useful in large companies and offices with their own extensive wireless networks. And could prove to be the next big thing, with the expanding market for municipal Wi-Fi. [source: Dr. Dobb's Portal]. Imagine that your entire city was covered by a high-speed wireless network. That means cheap (if not free) VoIP calls wherever you go.

In England, a company called Hutchinson 3G (or simply 3) has partnered with the popular VoIP service Skype to introduce the 3 Skypephone. The Skypephone allows users to make free cell phone calls to other Skype users. The phone can also make regular cell-phone calls to non-Skype users for the normal fees. Here's how it works:

To make a Skype call using the 3 Skypephone, you have to be on 3's cellular network.
To initiate a Skype call, find a Skype user in your phone's address book and press the big "Skype" button.
The call first goes over 3's cellular GSM network to a fixed Internet line, which then connects the call to Skype [source: mobileSift].
From your 3 Skypephone, you can make free VoIP calls to other Skype users whether they have a Skypephone or not. You can talk to Skype users on their PCs or using other Skype VoIP products.

The 3 Skypephone isn't currently available in the United States.

VoIP Call Monitoring

2008-03-13T11:39:00.000-07:00

VoIP has its distinct advantages and disadvantages. The greatest advantage of VoIP is price and the greatest disadvantage is call quality. For businesses who deploy VoIP phone networks -- particularly those who operate busy call centers (customer service, tech support, telemarketing, et cetera) -- call quality issues are both inevitable and unacceptable. To analyze and fix call quality issues, most of these businesses use a technique called VoIP call monitoring.

VoIP call monitoring, also known as quality monitoring (QM), uses hardware and software solutions to test, analyze and rate the overall quality of calls made over a VoIP phone network [source: ManageEngine]. Call monitoring is a key component of a business's overall quality of service (QoS) plan.

Newer Skype services are
equipped to handle
VoIP protocol.

Call monitoring hardware and software uses various mathematical algorithms to measure the quality of a VoIP call and generate a score. The most common score is called the mean opinion score (MOS). The MOS is measured on a scale of one to five, although 4.4 is technically the highest score possible on a VoIP network [source: TestYourVoIP.com]. An MOS of 3.5 or above is considered a "good call" [source: ManageEngine].

To come up with the MOS, call monitoring hardware and software analyzes several different call quality parameters, the most common being:

Latency -- This is the time delay between two ends of a VoIP phone conversation. It can be measured either one-way or round trip. Round-trip latency contributes to the "talk-over effect" experienced during bad VoIP calls, where people end up talking over each other because they think the other person has stopped speaking. A round-trip latency of over 300 millisecond is considered poor [source: TestYourVoIP.com].
Jitter -- Jitter is latency caused by packets arriving late or in the wrong order [source: SearchVoIP.com]. Most VoIP networks try to get rid of jitter with something called a jitter buffer that collects packets in small groups, puts them in the right order and delivers them to the end user all at once. VoIP callers will notice a jitter of 50 msec or greater [source: TestYourVoIP.com].
Packet loss -- Part of the problem with a jitter buffer is that sometimes it gets overloaded and late-arriving packets get "dropped" or lost [source: TestYourVoIP.com]. Sometimes the packets will get lost sporadically throughout a conversation (random loss) and sometimes whole sentences will get dropped (bursty loss) [source: TestYourVoIP.com]. Packet loss is measured as a percentage of lost packets to received packets.

There are two different types of call monitoring: active and passive. Active (or subjective) call monitoring happens before a company deploys its VoIP network. Active monitoring is often done by equipment manufacturers and network specialists who use a company's VoIP network exclusively for testing purposes [source: VoIP Troubleshooter.com]. Active testing can't occur once a VoIP network is deployed and employees are already using the system.

Passive call monitoring analyzes VoIP calls in real-time while they're being made by actual users [source: VoIP Troubleshooter.com]. Passive call monitoring can detect network traffic problems, buffer overloads and other glitches that network administrators can fix in network down time.

Another method for call monitoring is recording VoIP phone calls for later analysis. This type of analysis is limited, however, to what can be heard during the call, not what's happening on the actual network. This type of monitoring is usually done by human beings, not computers, and is called quality assurance.

Advantages of Using VoIP

2008-03-13T11:38:00.000-07:00

VoIP technology uses the Internet's packet-switching capabilities to provide phone service. VoIP has several advantages over circuit switching. For example, packet switching allows several telephone calls to occupy the amount of space occupied by only one in a circuit-switched network. Using PSTN, that 10-minute phone call we talked about earlier consumed 10 full minutes of transmission time at a cost of 128 Kbps. With VoIP, that same call may have occupied only 3.5 minutes of transmission time at a cost of 64 Kbps, leaving another 64 Kbps free for that 3.5 minutes, plus an additional 128 Kbps for the remaining 6.5 minutes. Based on this simple estimate, another three or four calls could easily fit into the space used by a single call under the conventional system. And this example doesn't even factor in the use of data compression, which further reduces the size of each call.

Let's say that you and your friend both have service through a VoIP provider. You both have your analog phones hooked up to the service-provided ATAs. Let's take another look at that typical telephone call, but this time using VoIP over a packet-switched network:

Click "Play" to see how packet switching works.

You pick up the receiver, which sends a signal to the ATA.
The ATA receives the signal and sends a dial tone. This lets you know that you have a connection to the Internet.
You dial the phone number of the party you wish to talk to. The tones are converted by the ATA into digital data and temporarily stored.
The phone number data is sent in the form of a request to your VoIP company's call processor. The call processor checks it to ensure that it's in a valid format.
The call processor determines to whom to map the phone number. In mapping, the phone number is translated to an IP address (more on this later). The soft switch connects the two devices on either end of the call. On the other end, a signal is sent to your friend's ATA, telling it to ask the connected phone to ring.
Once your friend picks up the phone, a session is established between your computer and your friend's computer. This means that each system knows to expect packets of data from the other system. In the middle, the normal Internet infrastructure handles the call as if it were e-mail or a Web page. Each system must use the same protocol to communicate. The systems implement two channels, one for each direction, as part of the session.
You talk for a period of time. During the conversation, your system and your friend's system transmit packets back and forth when there is data to be sent. The ATAs at each end translate these packets as they are received and convert them to the analog audio signal that you hear. Your ATA also keeps the circuit open between itself and your analog phone while it forwards packets to and from the IP host at the other end.
You finish talking and hang up the receiver.
When you hang up, the circuit is closed between your phone and the ATA.
The ATA sends a signal to the soft switch connecting the call, terminating the session.

Probably one of the most compelling advantages of packet switching is that data networks already understand the technology. By migrating to this technology, telephone networks immediately gain the ability to communicate the way computers do. It will still be at least a decade before communications companies can make the full switch over to VoIP. As with all emerging technologies, there are certain hurdles that have to be overcome. We'll look at those in the next section.

VoIP: Packet Switching

2008-03-13T11:37:00.000-07:00

A packet-switched phone network is the alternative to circuit switching. It works like this: While you're talking, the other party is listening, which means that only half of the connection is in use at any given time. Based on that, we can surmise that we could cut the file in half, down to about 4.7 MB, for efficiency. Plus, a significant amount of the time in most conversations is dead air -- for seconds at a time, neither party is talking. If we could remove these silent intervals, the file would be even smaller. Then, instead of sending a continuous stream of bytes (both silent and noisy), what if we sent just the packets of noisy bytes when you created them?

VoIP phone users can make calls using their Internet connection.

Data networks do not use circuit switching. Your Internet connection would be a lot slower if it maintained a constant connection to the Web page you were viewing at any given time. Instead, data networks simply send and retrieve data as you need it. And, instead of routing the data over a dedicated line, the data packets flow through a chaotic network along thousands of possible paths. This is called packet switching.

While circuit switching keeps the connection open and constant, packet switching opens a brief connection -- just long enough to send a small chunk of data, called a packet, from one system to another. It works like this:

The sending computer chops data into small packets, with an address on each one telling the network devices where to send them.
Inside of each packet is a payload. The payload is a piece of the e-mail, a music file or whatever type of file is being transmitted inside the packet.
The sending computer sends the packet to a nearby router and forgets about it. The nearby router send the packet to another router that is closer to the recipient computer. That router sends the packet along to another, even closer router, and so on.
When the receiving computer finally gets the packets (which may have all taken completely different paths to get there), it uses instructions contained within the packets to reassemble the data into its original state.

Packet switching is very efficient. It lets the network route the packets along the least congested and cheapest lines. It also frees up the two computers communicating with each other so that they can accept information from other computers, as well.