Passive tags that operate at frequencies up to 100 MHz are usually powered by magnetic induction, the same principle that drives the operation of household transformers. An alternating current in the reader coil induces a current in the tag's antenna coil, allowing charge to be stored in a capacitor, which then can be used to power the tag electronics. Information in the tag is sent back to the reader by loading the tag's coil in a changing pattern over time, which affects the current being drawn by the reader coil--a process called load modulation. To recover the identity of the tag, the reader simply decodes the change in current as a varying potential developed across a series resistance.
Unlike a transformer, the coils of a reader and a tag are separated in space, and coupling between the coils can occur only where the magnetic field lines of the reader coil intersect with the tag coil, the near field region (see figure 3). Beyond this distance the energy breaks away from the antenna as propagating waves that we call a radio signal; this is known as the far field region. The boundary of the near field and far field is governed by the frequency of the alternating current and is approximately limited to a distance of c/2pf; for example, at 13.56 MHz used by the ISO 15693 and 14443 standards, this distance is 3.6 meters, but at 915 MHz, used by EPCglobal, the range of the reader if based on near field coupling would be limited to six centimeters, reducing its usefulness.
Click for Figure
Note that even at the lower frequency it is not guaranteed a reader/tag pair will be able to exchange data up to the c/2pf distance. Unfortunately, the magnetic field strength also falls off fairly rapidly, proportional to a 1/d3 factor, where d is the distance from the center of the reader coil to the tag. If the field strength is too weak at a given distance, it will not be possible to provide the tag with the energy it needs to switch on. This effect can be mitigated by increasing the size of the reader coil and the tag coil, but for handheld readers and tags attached to small objects, there are obvious limitations. In practice, at 13.56 MHz, most systems operate with a range between 1 and 30 cm, considerably shorter than the near field limit.
To circumvent the range problem at higher frequencies, a different principle is used to build tags operating at frequencies above 100 MHz--namely, electromagnetic capture. The technique involves the use of electromagnetic waves that propagate from the antenna in the far field region to power the tag.
A high-frequency tag operates much as an old-fashioned crystal-set radio, which requires no battery because it is able to capture enough energy from the received signal. Because the tag is operating beyond the near field, however, data cannot be sent back to the reader using load modulation; instead, radio frequency backscatter must be used: the tag electronics changes the impedance of the antenna, reflecting back some of the incident RF energy to the reader (figure 4). The reader, using a sensitive receiver, decodes the ID of the tag from the pattern of reflections, expressed as a varying amplitude in the received signal. For far field communication, the energy delivered to the tag follows an inverse square law, and the return signal another inverse square law. Thus, the transmit power is attenuated by a 1/d4 law even before considering operational inefficiencies, where d is the separation of the tag and reader--a very rapid decline indeed, but the system can be made to work over a distance of three to four meters.
Click for Figure
Modern high-frequency tags, like the microprocessors in PCs, are beneficiaries of Moore's law. The laws of physics dictate the amount of energy that a reader can transmit to an RFID tag. The amount of energy required to power a digital circuit clocking at a particular frequency, however, has been falling annually as a result of advances in silicon technology that have le
Just how do those little things work anyway? Radio Frequency Identification
Many modern technologies give the impression they work by magic, particularly when they operate automatically and their mechanisms are invisible. A technology called RFID (radio frequency identification), which is relatively new to the mass market, has exactly this characteristic and for many people seems a lot like magic. RFID is an electronic tagging technology (see figure 1) that allows an object, place, or person to be automatically identified at a distance without a direct line-of-sight, using an electromagnetic challenge/response exchange. Typical applications include labeling products for rapid checkout at a point-of-sale terminal, inventory tracking, animal tagging, timing marathon runners, secure automobile keys, and access control for secure facilities.
Click for Figure
In fact, various forms of crude RFID have been used since World War II. In the 1960s the technology became more practical, but the applications since then have resulted in relatively small tag deployments in narrow high-value areas without much public visibility. Also, given a tag's small size and ability to be hidden or molded into the casing of a product, some people may have encountered RFID without realizing it was present.
In the last couple of years many RFID stories have appeared in the popular press. Why is RFID making a splash now, given that the idea is at least 40 years old? Most technologies have a window of opportunity for deployment, which is related to the scope of the problem it solves, the maturity of the technology, and the cost of deployment. On all three of these points the world has changed over the past 40 years. Inventory tracking is now necessary on an unprecedented scale to support growing consumer markets at low operating costs and to remain price competitive despite the relatively high labor cost in the developed countries. Furthermore, the components used to build the tags and tag readers have become more sophisticated. Today, they provide greater functionality, reading range, and speed of data transfer. As a result, they support the ability to accurately read a large number of co-located tags at the same time. Standards also play a role--an important new standard created by the former Auto-ID Center (whose work is now being carried forward by the not-for-profit EPCglobal) has recently brought together a number of influential organizations such as Wal-Mart, Tesco (UK), and the U.S. Department of Defense (DoD), all of which recognize the opportunity RFID brings to improve operational efficiencies.
Lastly, the ultimate incentive for deployment of a technology is cost. When the benefits and cost savings brought about by the technology are greater than the deployment cost, the time is right. Since tags would most often be attached to large inventories of relatively inexpensive products, the tags need to be inexpensive. Some analysts say a tag must cost less than 5 cents (others below 1 cent) for the technology to be truly competitive. By comparison, existing tagging technologies such as bar-code systems involve little more than the very low cost of printing lines on packaging. At present, RFID tags are in the 50-cent range for small quantities, a number that could be reduced to the target price if their use were to grow as expected.
Initially, commercial deployment is likely to focus on pallet- or crate-level tracking in a warehouse, and depending on its success, may lead to item-level tracking in the future. RFID could improve the efficiency of warehouse management considerably. RFID tags would allow crate identities to be checked at a distance when entering or leaving the building, whether or not the tag is directly visible. A bar code used in the same application could well be facing the wrong direction, making it impossible to scan automatically. Once RFID has proved beneficial and has been well established, economies of scale such as mass production s
He said:
One way to stem piracy is to offer consumers in emerging countries a low-cost PC, Ballmer said. "There has to be...a $100 computer to go down-market in some of these countries. We have to engineer (PCs) to be lighter and cheaper," he said.
No where did he actually blame PC hardware for piracy. He simply said that in the "lower" markets, there need to be cheaper PCs to help curb the piracy issue. Big difference in the two statements.
It's a vulnerability lotto! Mozilla got a spoofing vuln (assuming URL spoofing vuln, as the article is slashdotted, and I'm too lazy to view the Bug Traq lists)! At least it isn't as bad as IE....guess that stack protection with SP2 isn't helping with that one?
I do work for companies, although mostly small to medium-sized ones. If it took me 4 hours to re-install (and this is seriously low, more like 8 to re-install/join to domain/install other software/copy data across), because of a virus, I would be fired. 30 minutes, in and out, PC operational. If a back door is suspected, monitor at the firewall, for suspicious packets. This sounds like a worm though, since it took out so many nodes on the network. Yes, re-installing would be nice, but it never happens in the real world. Now, if a malicious user broke into the system, then yes, a complete re-install is warranted. It is instead I who feel sorry for your company, you waste too much time when a 30 minute removal tool can fix it. Besides, isn't this data encrypted? If not, well, thats part of the problem. Using something like a SQL front end to a database (where the info is), you wouldn't have an issue of desktop machines swiping server info, if it was just a virus.
At that, a backdoor would have to know whether or not a SQL server was being used to store data on, instead of the traditional file-on-a-file-server approach. If it is a back door, then yes, re-install. If it was Sasser, or something like that, just remove it.
In any event, their IT people should have had ghost images or something of these nodes after a fresh install. Would take a couple hours per node to get back up and running (minus the server).
And let's be honest- how popular are those viruses? Viruses are just like the biological ones, in order for a virus to survive in it's host "body", the virus must have as little side effects to the host as possible. The "perfect" viruses are the ones that can live in their host for years before being recognised, giving the virus plenty of time to spread to other hosts. The viruses that kill a host within 38 hours are failures, and soon dwindle out of existence. The last major destructive virus I remember was MyDoom.K I think, wiped out.xls,.doc, and.mdb.
There are removal tools out there guys. You don't actually *HAVE* to re-install it to remove an infection. Sounds like the CO DMV needs to hire someone who knows what they are doing!
Actually, if you have a crappy switch that either doesn't autonegotiate well, or has trouble talking to 10BT and 100BT at the same time, its a good reason to throw a 10/100 card in there.
In addition, transferring large files to your router sucks over 10BT (tar dumps of the FS, etc).
Further, some of us have seeing that puny 10BT light on our switch with all other nodes at 100BT.
apt-get install kernel-image-2.4.18-1-586tsc
2.2 is the default, but specifying bf24 on the boot prompt will install 2.4. And yes, still using the stable tree. Debian isn't *THAT* out of date, I use stable on my servers, and testing on my workstations.
most likely it was hardware reasons, Linux likes to freak out with a Kernel Panic when it does crash. However, there is a nice little place where Linux stores its logs (system),/var/log/messages./var/log is where all logs are kept BTW.
As a former resident of SC, I can say that this is indeed false. Insurance is required in SC, but about 10% (I think, can't remember the statistic) of drivers in SC don't bother to get insured.
And then you have cities like Laurel, 8 mi outside of Billings, which can only get broadband through one shitty ISP, Cable MT. They have a total lockdown of Laurel (no DSL), and no one seems to want to offer service for Laurel. Laurel, BTW, is not *THAT* small of a town, maybe 10k or so.
In any event, its not really that big of a deal. Is a nazi really going to smack you a few times with a baseball bat in front of witnesses? I think not. The ability to double-check the system would be nice, although there would have to be watermarks, etc, on the actual reciept tickets as well to prove that they are geniune.
Ask yourself this, would you take the risk of getting capped for not voting for someone (again, unlikely), if you could double-check your vote in the event of a close win (or loss) by a canidate?
Well, how about this: a voter recieves a number identifier instead of an identifier that could be tied directly to them. The voter can then, after the votes are tallied, go to some state.us site and verify that his/her number matches who he/she voted for. The broken kneecaps rule wouldn't work, as the nazis can't confirm its actually THAT person's reciept, they could have just found one that said what they wanted it to say. I'm sure after a while there could be a large stack of these reciepts in the trash that they could then use to give to the nazi party. The paper reciept (the one used for official counts) would then be printed and stored in a safe location inside the machine (perhaps have obvious identifiers to the reciepts, such as MANUAL RECOUNT on the background of the official one, and VERIFICATION COPY printed on the back of the copy John Doe or Jane Doe gets). Best of both worlds, really, IMHO.
Everyone is aware this is just a policy that can be edited, correct? Its not that useful of a feature anyways, due to the numerous vulnerabilities that Windows has. In any event, if an attacker can get as far as to display a page requesting a login (presumably at boot), you're already hosed anyways. In any event, having a mobile device tied to a domain would be a pain, always having to select "logon to local computer" at boot.
Ah yes, for the old "this is to protect your password, only Windows can intercept this keystroke" deal. Not very useful, IMHO. Kind of like placing an electrified barb wire fence around a perimeter where there is a wide-open tunnel under the main gate.
Slashdot Mirror
How it Works
Operating Principles
Passive tags that operate at frequencies up to 100 MHz are usually powered by magnetic induction, the same principle that drives the operation of household transformers. An alternating current in the reader coil induces a current in the tag's antenna coil, allowing charge to be stored in a capacitor, which then can be used to power the tag electronics. Information in the tag is sent back to the reader by loading the tag's coil in a changing pattern over time, which affects the current being drawn by the reader coil--a process called load modulation. To recover the identity of the tag, the reader simply decodes the change in current as a varying potential developed across a series resistance.
Unlike a transformer, the coils of a reader and a tag are separated in space, and coupling between the coils can occur only where the magnetic field lines of the reader coil intersect with the tag coil, the near field region (see figure 3). Beyond this distance the energy breaks away from the antenna as propagating waves that we call a radio signal; this is known as the far field region. The boundary of the near field and far field is governed by the frequency of the alternating current and is approximately limited to a distance of c/2pf; for example, at 13.56 MHz used by the ISO 15693 and 14443 standards, this distance is 3.6 meters, but at 915 MHz, used by EPCglobal, the range of the reader if based on near field coupling would be limited to six centimeters, reducing its usefulness.
Click for Figure
Note that even at the lower frequency it is not guaranteed a reader/tag pair will be able to exchange data up to the c/2pf distance. Unfortunately, the magnetic field strength also falls off fairly rapidly, proportional to a 1/d3 factor, where d is the distance from the center of the reader coil to the tag. If the field strength is too weak at a given distance, it will not be possible to provide the tag with the energy it needs to switch on. This effect can be mitigated by increasing the size of the reader coil and the tag coil, but for handheld readers and tags attached to small objects, there are obvious limitations. In practice, at 13.56 MHz, most systems operate with a range between 1 and 30 cm, considerably shorter than the near field limit.
To circumvent the range problem at higher frequencies, a different principle is used to build tags operating at frequencies above 100 MHz--namely, electromagnetic capture. The technique involves the use of electromagnetic waves that propagate from the antenna in the far field region to power the tag.
A high-frequency tag operates much as an old-fashioned crystal-set radio, which requires no battery because it is able to capture enough energy from the received signal. Because the tag is operating beyond the near field, however, data cannot be sent back to the reader using load modulation; instead, radio frequency backscatter must be used: the tag electronics changes the impedance of the antenna, reflecting back some of the incident RF energy to the reader (figure 4). The reader, using a sensitive receiver, decodes the ID of the tag from the pattern of reflections, expressed as a varying amplitude in the received signal. For far field communication, the energy delivered to the tag follows an inverse square law, and the return signal another inverse square law. Thus, the transmit power is attenuated by a 1/d4 law even before considering operational inefficiencies, where d is the separation of the tag and reader--a very rapid decline indeed, but the system can be made to work over a distance of three to four meters.
Click for Figure
Modern high-frequency tags, like the microprocessors in PCs, are beneficiaries of Moore's law. The laws of physics dictate the amount of energy that a reader can transmit to an RFID tag. The amount of energy required to power a digital circuit clocking at a particular frequency, however, has been falling annually as a result of advances in silicon technology that have le
Bloody thing's getting slow here:
Just how do those little things work anyway?
Radio Frequency Identification
Many modern technologies give the impression they work by magic, particularly when they operate automatically and their mechanisms are invisible. A technology called RFID (radio frequency identification), which is relatively new to the mass market, has exactly this characteristic and for many people seems a lot like magic. RFID is an electronic tagging technology (see figure 1) that allows an object, place, or person to be automatically identified at a distance without a direct line-of-sight, using an electromagnetic challenge/response exchange. Typical applications include labeling products for rapid checkout at a point-of-sale terminal, inventory tracking, animal tagging, timing marathon runners, secure automobile keys, and access control for secure facilities.
Click for Figure
In fact, various forms of crude RFID have been used since World War II. In the 1960s the technology became more practical, but the applications since then have resulted in relatively small tag deployments in narrow high-value areas without much public visibility. Also, given a tag's small size and ability to be hidden or molded into the casing of a product, some people may have encountered RFID without realizing it was present.
In the last couple of years many RFID stories have appeared in the popular press. Why is RFID making a splash now, given that the idea is at least 40 years old? Most technologies have a window of opportunity for deployment, which is related to the scope of the problem it solves, the maturity of the technology, and the cost of deployment. On all three of these points the world has changed over the past 40 years. Inventory tracking is now necessary on an unprecedented scale to support growing consumer markets at low operating costs and to remain price competitive despite the relatively high labor cost in the developed countries. Furthermore, the components used to build the tags and tag readers have become more sophisticated. Today, they provide greater functionality, reading range, and speed of data transfer. As a result, they support the ability to accurately read a large number of co-located tags at the same time. Standards also play a role--an important new standard created by the former Auto-ID Center (whose work is now being carried forward by the not-for-profit EPCglobal) has recently brought together a number of influential organizations such as Wal-Mart, Tesco (UK), and the U.S. Department of Defense (DoD), all of which recognize the opportunity RFID brings to improve operational efficiencies.
Lastly, the ultimate incentive for deployment of a technology is cost. When the benefits and cost savings brought about by the technology are greater than the deployment cost, the time is right. Since tags would most often be attached to large inventories of relatively inexpensive products, the tags need to be inexpensive. Some analysts say a tag must cost less than 5 cents (others below 1 cent) for the technology to be truly competitive. By comparison, existing tagging technologies such as bar-code systems involve little more than the very low cost of printing lines on packaging. At present, RFID tags are in the 50-cent range for small quantities, a number that could be reduced to the target price if their use were to grow as expected.
Initially, commercial deployment is likely to focus on pallet- or crate-level tracking in a warehouse, and depending on its success, may lead to item-level tracking in the future. RFID could improve the efficiency of warehouse management considerably. RFID tags would allow crate identities to be checked at a distance when entering or leaving the building, whether or not the tag is directly visible. A bar code used in the same application could well be facing the wrong direction, making it impossible to scan automatically. Once RFID has proved beneficial and has been well established, economies of scale such as mass production s
He said:
One way to stem piracy is to offer consumers in emerging countries a low-cost PC, Ballmer said. "There has to be...a $100 computer to go down-market in some of these countries. We have to engineer (PCs) to be lighter and cheaper," he said.
No where did he actually blame PC hardware for piracy. He simply said that in the "lower" markets, there need to be cheaper PCs to help curb the piracy issue. Big difference in the two statements.
It's a vulnerability lotto! Mozilla got a spoofing vuln (assuming URL spoofing vuln, as the article is slashdotted, and I'm too lazy to view the Bug Traq lists)! At least it isn't as bad as IE....guess that stack protection with SP2 isn't helping with that one?
But perpetual protection of Mickey Mouse is ok, assuming enough funds have been paid to corrupt officials.
I do work for companies, although mostly small to medium-sized ones. If it took me 4 hours to re-install (and this is seriously low, more like 8 to re-install/join to domain/install other software/copy data across), because of a virus, I would be fired. 30 minutes, in and out, PC operational. If a back door is suspected, monitor at the firewall, for suspicious packets. This sounds like a worm though, since it took out so many nodes on the network. Yes, re-installing would be nice, but it never happens in the real world. Now, if a malicious user broke into the system, then yes, a complete re-install is warranted. It is instead I who feel sorry for your company, you waste too much time when a 30 minute removal tool can fix it. Besides, isn't this data encrypted? If not, well, thats part of the problem. Using something like a SQL front end to a database (where the info is), you wouldn't have an issue of desktop machines swiping server info, if it was just a virus.
At that, a backdoor would have to know whether or not a SQL server was being used to store data on, instead of the traditional file-on-a-file-server approach. If it is a back door, then yes, re-install. If it was Sasser, or something like that, just remove it.
In any event, their IT people should have had ghost images or something of these nodes after a fresh install. Would take a couple hours per node to get back up and running (minus the server).
And let's be honest- how popular are those viruses? Viruses are just like the biological ones, in order for a virus to survive in it's host "body", the virus must have as little side effects to the host as possible. The "perfect" viruses are the ones that can live in their host for years before being recognised, giving the virus plenty of time to spread to other hosts. The viruses that kill a host within 38 hours are failures, and soon dwindle out of existence. The last major destructive virus I remember was MyDoom.K I think, wiped out .xls, .doc, and .mdb.
There are removal tools out there guys. You don't actually *HAVE* to re-install it to remove an infection. Sounds like the CO DMV needs to hire someone who knows what they are doing!
two words:
/24!
ban subnet
Ok, so thats a tad harsh, but come on, everyone likes to do it, ban a
Actually, if you have a crappy switch that either doesn't autonegotiate well, or has trouble talking to 10BT and 100BT at the same time, its a good reason to throw a 10/100 card in there.
In addition, transferring large files to your router sucks over 10BT (tar dumps of the FS, etc).
Further, some of us have seeing that puny 10BT light on our switch with all other nodes at 100BT.
apt-get install kernel-image-2.4.18-1-586tsc 2.2 is the default, but specifying bf24 on the boot prompt will install 2.4. And yes, still using the stable tree. Debian isn't *THAT* out of date, I use stable on my servers, and testing on my workstations.
Yeah, but the latency sucks, and it *REALLY* sucks if you lose a "packet" due to a collision!
Shoot, forgot the download link: HERE .
The file is downloading as I type this, hopefully it will finish so I can mirror it.
HERE.
NOTE: Only the source code is mirrored, site is way too slow to mirror the rest!
most likely it was hardware reasons, Linux likes to freak out with a Kernel Panic when it does crash. However, there is a nice little place where Linux stores its logs (system), /var/log/messages. /var/log is where all logs are kept BTW.
As a former resident of SC, I can say that this is indeed false. Insurance is required in SC, but about 10% (I think, can't remember the statistic) of drivers in SC don't bother to get insured.
http://216.239.57.104/search?q=cache:C56AMXjSLjoJ: letsroll911.org/ipw-web/bulletin/bb/viewtopic.php% 3Ft%3D91+%22george+bush+and+colin+powell%22+%22are +related%22&hl=en
:)
To quote: George Bush and Colin Powell are related by Royal Blood.
Please send my invite to cpace@hnsg.net
And then you have cities like Laurel, 8 mi outside of Billings, which can only get broadband through one shitty ISP, Cable MT. They have a total lockdown of Laurel (no DSL), and no one seems to want to offer service for Laurel. Laurel, BTW, is not *THAT* small of a town, maybe 10k or so.
In any event, its not really that big of a deal. Is a nazi really going to smack you a few times with a baseball bat in front of witnesses? I think not. The ability to double-check the system would be nice, although there would have to be watermarks, etc, on the actual reciept tickets as well to prove that they are geniune.
Ask yourself this, would you take the risk of getting capped for not voting for someone (again, unlikely), if you could double-check your vote in the event of a close win (or loss) by a canidate?
Well, how about this: a voter recieves a number identifier instead of an identifier that could be tied directly to them. The voter can then, after the votes are tallied, go to some state.us site and verify that his/her number matches who he/she voted for. The broken kneecaps rule wouldn't work, as the nazis can't confirm its actually THAT person's reciept, they could have just found one that said what they wanted it to say. I'm sure after a while there could be a large stack of these reciepts in the trash that they could then use to give to the nazi party. The paper reciept (the one used for official counts) would then be printed and stored in a safe location inside the machine (perhaps have obvious identifiers to the reciepts, such as MANUAL RECOUNT on the background of the official one, and VERIFICATION COPY printed on the back of the copy John Doe or Jane Doe gets). Best of both worlds, really, IMHO.
Everyone is aware this is just a policy that can be edited, correct? Its not that useful of a feature anyways, due to the numerous vulnerabilities that Windows has. In any event, if an attacker can get as far as to display a page requesting a login (presumably at boot), you're already hosed anyways. In any event, having a mobile device tied to a domain would be a pain, always having to select "logon to local computer" at boot.
Ah yes, for the old "this is to protect your password, only Windows can intercept this keystroke" deal. Not very useful, IMHO. Kind of like placing an electrified barb wire fence around a perimeter where there is a wide-open tunnel under the main gate.
This unit has a built-in three finger salute, to quote:
Around the sides:
Compact Flash slot
Memory Stick Pro slot
Hold switch
Standby button
Ctrl-Alt-Del switch
Mirror is here, although I don't know for how long!
Actually, its called the Millennium Digital Commerce Act of 2000.
See it HERE.
Story when it happened HERE.