Binh Nguyen's Blog: wireless

Showing posts with label wireless. Show all posts

Wednesday, September 19, 2018

WiFi Check Security Script, Random Stuff, and More

- China’s next-generation high-performance turbofan jet engines such as the domestically developed WS-15 turbofan engine are underpowered and continue to show various performance issues. One of the principal reasons for the poor performance of China’s military aviation industry when it comes to the development and production of engines is that its past overreliance on reverse engineering has prevented the industry from obtaining the necessary know-how and experience that comes from prolonged R&D phases as well as infrastructural support.

https://thediplomat.com/2018/08/russia-confirms-delivery-of-10-su-35-fighter-jets-to-china-by-years-end/

- "I am convinced we are seeing a steady erosion of the gullibility of the public," said Professor Archer, whose findings – the longest continual survey of its kind worldwide – are published on Wednesday in the journal Evolution; Education and Outreach.

"Once, you couldn't check these things. If someone in a position of power – a priest – told you this is how the world was, you didn't have the power to check that. Now [due to the internet] everyone does, and it's exposing the emperor's new clothes."

Professor Archer grew up in the United States, surrounded by people who believed in creation. When he arrived at the University of NSW and taught his first class in evolution, he wanted to see how his students felt so he could tailor his teaching.

"My colleagues thought it was a ridiculous question," he said. "They thought nobody in their right mind would be a creationist in Australia."

When he saw the results, he was relieved; only 10 per cent believed in creationism. His Australian colleagues were shocked that the number was so high. However, almost two-thirds did believe God had some kind of influence on the process.

For three decades, Professor Archer has asked an average of 530 students a year to tick one of four boxes; that God created people as they are; that God guided the process of evolution; that God had no part in evolution; or they had no view.

He expected the numbers of students ticking the first two boxes to stay the same the as years went by, and perhaps even rise (creationists, as he knows from the US, are enthusiastic evangelists). So he was stunned by the rapid fall.

"Conversely, the idea that God had nothing to do with the evolution of humans, which started out at around 25 per cent, streaked upwards until it became the dominant view in the class," Professor Archer said.

He believes his sample was representative of the general population; studies in the US show universities were not influencing young people's religious beliefs, Professor Archer said.

To him, the most probable explanation is the internet. "The web is filled with solid explanations about the whole world, including people," he said. "When you give people access to actual information, superstitions struggle to survive."

https://www.smh.com.au/education/gullibility-eroded-why-a-generation-chose-science-over-god-20180817-p4zy7j.html

- One of the most common explanations for the rise of right-wing populist anger is the growing gap between rich and poor in the country. Expressions of class resentment among AfD and PEGIDA supporters are hardly unusual. But these people are hardly a monolithic class block. One marcher himself even characterized some of his fellow protesters as "simple-minded people who live from social benefits and aren't able to reflect on the whole situation."

Instead, one leitmotif of right-wing populism in Germany is envy. Leftist counterdemonstrators are given preferential treatment, the marchers fumed. Refugees are showered with money, designer clothes and state-of-the-art mobile phones while working Germans struggle to get by. And political and media elite line their pockets and have no contact any more with "common people." This is actually one similarity between Marxist and right-wing populist dogma: If you don't like what you read in the papers, it's because the journalists are all bought and paid for. These arguments are repeated over and over by today's German right.

Jealousy is part of human nature, going back to the Bible and far beyond it. But the advent of social media and the attendant filter bubbles has changed the environment in which this ugly human characteristic exists, augmenting it and making it more easily mobilized to political ends, often by propagating misinformation. That was one major reason why the air crackles with such hostility in Chemnitz right now.

https://www.dw.com/en/lessons-from-chemnitz-eastern-germanys-right-wing-protesters-awash-in-anxiety/a-45326613

- Dubbed “Tin Shield” by NATO, the highly mobile radar system has been used in variants of the Russian air defense system S300.

Many countries including Iran, China and Russia are currently operating different iterations of the air defense system.

Defense Blog wrote that a company “associated with Russia” had tried to block Iskra from selling the system to the US, on the grounds that it had failed to pay royalties for using patented technologies.

Russia is known to have developed sophisticated radar technologies for its air defense systems, enabling them to detect and target aircraft and missiles of various types in lower and higher altitudes.

The US, on the other hand, has struggled to develop battle-tested system that can offer the same level of protection.

The vulnerability of American missile defense systems became apparent December last year, when Yemeni Scud-type missiles were able to bypass US-made Patriot missile shields and land in Saudi Arabia’s capital, Riyadh.

https://www.presstv.com/Detail/2018/09/03/573055/US-Tin-shield-3d-radar-ukraine

- SBS aims to inspire all Australians to explore and appreciate our diverse world and by doing so contribute to a cohesive society. It's a purpose which drives and motivates our team and the reason we love doing what we do.

https://www.seek.com.au/job/37174515?type=standout

"I was so naive about different skill sets. I thought if somebody had a high IQ, they could be good at everything. And the idea that you needed to blend these different types of skills together, that always continued to surprise me," said the Microsoft co-founder.

"There was this simple idea of smartness and it could go and solve everything — I wish I had known better than to think that."

https://www.cnbc.com/2018/09/05/bill-gates-shares-his-best-advice-for-students.html

Tuesday, January 8, 2013

Wireless/Behavioural Security Analysis and Bugs

I previously theorised ('Cloud' document) about wide spectrum radio solutions to help deal with the problem of expensive/continuous hardware ugprades of telecommunications infrastructure. The CSIRO has since built something along these lines.
http://www.itwire.com/business-it-news/technology/53040-csiro-debuts-10gbps-microwave-backhaul-technology

What has interested me even more though is recent work in software based radio technology. A similar concept but what I'm particularly interested in is the flexibility it will provide with regards to offensive opeations (Electronic Warfare and Jamming).
http://www.h-online.com/open/features/One-software-radio-to-rule-them-all-1775971.html

As many people are probably aware GPS is being updated/upgraded to deal with various known threats such as susceptibility jamming, substandard performance in enclosed areas, and so on. One complementary solution/alternative being considered is Leica's 'Jigsaw'.
http://www.gizmodo.co.uk/2013/01/move-over-gps-a-new-positioning-system-has-you-in-its-sights/
http://www.newscientist.com/article/mg21728985.600-new-positioning-technology-could-compete-with-gps.html
http://mining.leica-geosystems.com/products/
http://mining.leica-geosystems.com/products/unified-hardware-platform-uhp/

Variation of 'Adaptive Networking' concept I was playing with in the original 'Cloud' document.
http://arstechnica.com/gadgets/2013/01/a-wireless-router-that-tracks-user-activity-but-for-a-good-reason/

I've spoken about interlaced attacks, and attacks which involve disrupting activity (they tend to fail open though there are a number of devices which allow you the option of having them fail closed at the expense of ) of security systems by overloading or confusing them in the 'Convergence' report before. The following of a study of how performance drops off in the real world using entry level enterprise firewalls from several well known vendors.
http://www.spirent.com/White-Papers/Broadband/PAB/Broadband-Testing_Entry-Level_Enterprise_Firewall_Test_Report

A variation of my 'Cognitive Fingerprinting' work as outlined in the 'Cloud' and 'Convergence' reports. Basically instead of using purely signatures we're going to look at behaviour as the main means of detecting whether a file is good or bad. Of course, this will be on top of existing security models/systems but something we need to think about is how even this can be bypassed. Some recent research I've come across seems to suggest that many sandbox type solutions that are used to detect presence of malware can be rather obvious. Countermeasures are being deployed which means that only 1/3 of all malware may be being picked up. More thought required...
http://www.newscientist.com/article/mg21728983.100-unmasking-the-cyber-saboteurs-whoever-they-are.html
http://www.newscientist.com/article/mg21728985.300-mapping-malwares-genome-to-fight-future-attacks.html

Neat way of increasing collaboration from the perspective of defense.
http://www.newscientist.com/article/mg21428684.600-why-we-may-never-know-who-created-flame-virus.html

Interesting graph of where your system is likely to get infected by a virus on the Internet. Not sure of it's overall validity...
http://www.newscientist.com/data/images/archive/2898/28985301.jpg

Details surrounding NSA 'Perfect Citizen' program to protect critical infrastructure becoming clearer.
http://phys.org/news/2012-12-privacy-group-nsa.html
http://epic.org/2012/12/epic-comments-on-federal-cyber.html
http://news.cnet.com/8301-1023_3-57560644-93/revealed-nsa-targeting-domestic-computer-systems-in-secret-test/
http://www.examiner.com/article/perfect-citizen-program-tests-security-of-u-s-utility-infrastructure
http://www.fiercesmartgrid.com/story/nsa-secret-cyber-security-testing-no-longer-secret/2012-12-26

Microsoft email Exchange/Outlook plugin to block reply all, forward option. Still doesn't deal with the 'analogue hole' problem though. Namely, taking a screenshot, a picture of your monitor itself, or even just (manually or automatically) copying and pasting the contents of the email in question itself and then relaying this on to the desired recipients.
http://research.microsoft.com/en-us/projects/researchdesktop/noreplyall.aspx

A more comprehensive Microsoft Data Loss Prevention (DLP) solution.
http://www.microsoft.com/exchange/en-us/information-protection-and-control.aspx

Vacuum your laptop/netbook ventilation ports regularly. Not doing so can result in higher dust build up, higher temperatures and fan speed, power consumption, etc... As stated previously, design of portable systems is always a compromise between performance, size, power consumption, and so on. If I had a way of being able to alter shell design without comprimising structural rigidity and resale value I would use it in a heartbeat.

The article that I was referring to in my previous post with regards to how the wealthy don't always produce more jobs.
http://www.bloomberg.com/news/2012-07-20/top-2-not-job-creators-or-millionaires-in-tax-debate.html

http://en.wikipedia.org/wiki/Tabula_rasa
http://forums.whirlpool.net.au/forum-replies.cfm?t=1310314
http://www.ynetnews.com/articles/0,7340,L-4300066,00.html

Bugs of the Week

Sega's/Sports Interactive's Football Manager Series (most of these apply to 2009 but some apply to only earlier versions)
- when operating in small window mode some fields/words will overlap making it sometimes impossible to navigate
- sometimes go on holiday mode doesn't stop before the play of a game on that particular day. Would like more 'predictable' behaviour

Microsoft's/Big Huge Game's Rise of Nations
Not really a bug. Sometimes I modify lines in rules.xml file so that I can tweak the game rules (population limits, resources, etc...) to make it easier/harder depending on my mood. I've discovered that depending on the total number of units and movement currently occuring underlying hardware performance becomes a major limiting factor. Just have to be careful.

KNetWalk
Opens to a rediculous default window size on a Netbook (not sure about other platforms as yet). Neat game though (fun for those who enjoy mazes) and each puzzle is reasonably short/easy (depending on level).

NeverPutt
Algorithm for finding direction to hole doesn't correctly identify best/easiest pathway to goal all the time which means some awkward/impossible starting directions are possible. Believe that it may be limited to holes where a certain terminal/short distance condition is triggered.

SuperTux
Basically a clone of SuperMario/Sonic the Hedgehog style games. Not really a bug but one thing I've always wanted to do in these games is to have more freedom with regards to going backwards and choosing another pathway through the game (understand the underlying hardware limitations of the consoles at the time though).

News Website (further details not disclosed for reasons of security and reputation)
Various uncaught exceptions after turning off JavaScript.

E-Commerce Website (further details not disclosed for reasons of security and reputation)
Website started sending refund messages to people who weren't involved in a recent mix up/pricing error.

HPM Powerboard
Purchased this a while back because it had a lot (12) of sockets and built-in RF/EM noise suppression. Lately been having problems with it though. It doesn't seem to smooth the power supply out. It seems to be cutting power in/out now. Believe it may simply be malfunctioning. Difficult to diagnose/fix personally though due to strange/unique screws being used in casing. Hoping still under warranty.

- as usual thanks to all of the individuals and groups who purchase and use my goods and services
http://sites.google.com/site/dtbnguyen/
http://dtbnguyen.blogspot.com.au/

Friday, October 12, 2012

More Security, Oscilloscope, and Wireless Foo

I've been experimenting further with Jaycar's YN8306. Dramatic increase in sensitivity once covers are taken off. Was able to see quadruple the number of access points at one test point than previously. Suspect that while some of the gaps in other USB wireless adapters that I've seen are for cooling but I believe that a secondary purpose may be to increase wireless signal permeability. Did some minor experiments with regards to different materials as an alternative for surrounding device but am surprised just how permeable/impermeable some substances are. Clear plastic, glass, can cut the sensitivity level significantly. Suspect that a cage type arrangement that protects the PCB but still allows it to 'breath' may be the best option. Would have to be careful with regards to turning it into a Faraday Cage type arrangement though.

http://en.wikipedia.org/wiki/Faraday_cage

While the device is advertised as being a 500mW device it's capable to 1000mW. Use the 'iw' command to change region and boost the possible transmission power (you'll notice that many chipsets run at lower power ranges for regional/legal reasons and to reduce power consumption. If you've ever analysed power consumption on mobile devices you'll realise how large of an impact it can have on battery life so turn off wireless capability whenever possible. It also helps with regards to security since there have been instances in the past of remote attacks (on poorly implemented network stacks) that have resulted in significant comprimises of system security didn't require authentication.).

It uses a combination of a 5dB external antenna and a single internal panel/smart/active/metamaterial antenna (unlike the Alfa's which often come with two external antenna combination). I may try to modify it to use a more conventional antenna system to see whether this would result in increased sensitivity but I suspect that this may require PCB modification (use a multimeter/continuity tester to understand how the thing is laid out) so I'll leave that for the less expensive D-Link DWA-125 A3.

http://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29
http://en.wikipedia.org/wiki/Active_antenna
http://en.wikipedia.org/wiki/Smart_antenna

For those people who think it's easy to discern a signal from an existing waveform is simple think again. For people who watch the movies it's commonly assumed that there are programs and/or savants that can automatically distinguish a multiplexed signal from an existing waveform. Pure statistical analysis is possible but as we've seen with automated network traffic classification it is prone to false positives. Something I have been experimenting with is embedding or extracting particular instruments from songs as a means of investigating the possibilities in regards to stenography. As others have discovered it's not as simple as you think. It's possible but seeing as though songs are meant to molded together and embedding/multiplexing signals is the converse things are a lot of more complex. There are so many choices with regards to multiplexing, modulation, encryption, encoding, and you can even burst the traffic to make it appear as though it's simply random noise. I guess the only way you can assure that your power/existing infrastructure/communications doesn't have another signal multiplexed over it is to have equipment that have basically perfect waveforms (easier said than done) or have waveforms that are 'extremely' predictable. From this extracting any aberrations from the existing waveform should be a simple process of determining the difference between the final, modified waveform and the original waveform. Another alternative is using a common noise filter to find the primary signal and finding the difference between the filtered signal and the final waveform.

Have been thinking about communication system compromises. If we can assume a one to one, bit for bit representation of data then we can develop a means of accounting for the data that goes in/out. Of course, this only works for stream based ciphers. It doesn't really work for block based cipher systems. However, as long as the relationship between the the information coming in can be represented by a formula going out then we should be able to determine whether or not you may have been infected and therefore need to take precautions to protect your communications.

http://en.wikipedia.org/wiki/Stream_cipher
http://en.wikipedia.org/wiki/Block_cipher

I'm guessing the same could be roughly achieved with power usage as well. The difference in the amount of power that is consumed while a phone is actually active compared to when it is in standby mode is drastic (see figures/specifications for any phone. You can track it using a program such as 'Android Battery Dog'.). By using relevant power measurement/graphing software, having an idea of how the power consumption should occur under various conditions, having an understanding battery conditioning (age/usage will obviously result in reduced battery capacity) you can achieve a gain a better understanding of what is normal behaviour and what looks like a compromised communication device.

A variation of a project/idea I've been pursuing for a while.
http://gcn.com/articles/2012/06/14/nsa-tracking-data-life-cycle.aspx

I called it 'Algorithmic Masking' (their program seems to be a combination of 'Automated Research' (some other research I've been pursuing) and 'Algorithmic Masking' (published in 'Convergence' document)) though and didn't intend for it to be used for national security purposes though. I originally came up with it to protect the privacy of consumers in the cloud space. Either way, given the amount of data that the NSA are dealing with and the analysis that they want to do it will be a spectacular program/project if it pans out.

Been playing around with flux gel while soldering but also using higher quality solder/solder with a lower melting point. Suspect that the latter may be the better option. Incredibly easier to work with.

Flying Saucer Declassified (though knowledge of these programs have been around for a long time now).
http://news.cnet.com/8301-17938_105-57527236-1/declassified-air-force-plans-for-a-flying-saucer/
http://www.networkworld.com/community/blog/future-drone-surveillance-swarms-cyborg-insect-drones

If you don't have a spare system available, nested VM's are more than possible but would only recommend if you can supply at least the following for the nested VM:
- 2GB RAM
- 2 CPU
- 20GB HDD
- Intel Network Adapter (compatibility reasons)

For the actual system:
- 6GB/8GB RAM
- i3 or higher
- the bigger your HDD the better

http://blogs.citrix.com/2011/01/23/xenserver-in-virtualbox/
http://magictrevor.wordpress.com/2012/05/09/esxi-5-on-virtualbox/
http://www.virtualbox.org/manual/ch06.html

https://www.virtualbox.org/ticket/7842
http://www.sysprobs.com/install-mac-snow-leopard-1063-oracle-virtualbox-32-apple-intel-pc
https://forums.virtualbox.org/viewtopic.php?f=22&t=31104
http://forums.whirlpool.net.au/forum-replies.cfm?t=1993468&p=-1&#bottom

Really neat and quick if you haven't memorised the resister charting system yet.
http://www.hobby-hour.com/electronics/resistorcalculator.php

Interesting reading if you're interested in Security Engineering.
http://www.cl.cam.ac.uk/~rja14/book.html

A way to concatenate the PDF files if you require.

http://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/

Alternative to when you don't have de-solder braid available is using copper wire (I use stranded wire from any broken network cables or coax cable that I around).
http://letsmakerobots.com/node/9269

http://news.cnet.com/8301-17938_105-57530019-1/dna-decay-rate-makes-jurassic-park-impossible/

- as usual thanks to all of the individuals and groups who purchase and use my goods and services
http://sites.google.com/site/dtbnguyen/
http://dtbnguyen.blogspot.com.au/

Wednesday, September 19, 2012

Automated Research and Some More Wireless Foo

One of the things that I sometimes wonder is whether or not Australia is lucky or unlucky in being so geographically isolated. Some industries (Airline and Motoring are probably the most recent and notable examples that come to mind) have not been provided with a level playing field when compared with the rest of the world. They've either been playing with one hand tied behind their back or others have. They haven't learnt to adapt. I think this is what happened with another industry that I recently had interactions with. Overseas, firms in this particular sector have advanced significantly over local competitors most particuarly in the clever use of technology. I've been thinking about this issue more though. Some of the concepts mentioned in my previous report (Convergence Effect)(such as 'Automated Research', http://dtbnguyen.blogspot.com/2012/03/automated-research.html) have had significant resources allocated to them but it's becoming clearer to me just how far we can push it. Data mining, searching, statistical analysis, and report writing are all processes that can be significantly automated with sufficient knowledge and application of technology (I'll provide a more detailed framework on how to achieve this in the context of Security analysis in my report on, 'Cloud and Internet Security' (about 557+ pages/155K+ words now) but obviously it can be used in other contexts as well).

http://www.businessweek.com/articles/2012-09-13/watch-out-google-facebook-s-social-search-is-coming#r=shared

In my recent experiments I've obviously been experimenting with various different USB wireless adapters. One of them was the D-Link DWA-125 A3 (rt5370sta), another was the NetGear WNDA4100 (rt3573sta, you need to modify the driver to add support for the new chipset, http://ubuntuforums.org/showthread.php?t=1942689), while another was Jaycar's YN8306 (all Ralink chipets funnily enough with decent Linux support, http://www.ralinktech.com/en/04_support/support.php?sn=501). Clearly, after doing a lot of experimental work I've discovered a lot about antenna technology as well as the current state of wireless technology out there. One of the things I didn't realise is how drastic some of the differences could be between revisions of both adapter and chipset. My original purchase of the YN8306 seemed to be reasonable but the performance was nothing spectacular (Ralink 3070L). After discovering the USB port was somewhat loose (it was constantly losing grip of the cable) I exchanged it for another one but discovered something similar so this time I opened up the device and made some modifications (extra solder to bolster the strength of the USB port). While I was in there I noticed that the chipset had been upgraded to the Ralink 3072L. My thoughts regarding the Rev A were that it was good but didn't have the level of sensitivity that I thought it would. Rev B was a bit different though. Based on initial observations it may be at least 20% stronger with regards to sensitivity when compared to the Rev A and transfer rates were far less likely to fluctuate. A significantly better device overall.

With my recent incursions into antenna design I should probably extrapolate on what exactly I mean. I've torn apart anything and everything that I could possibly get my hands on and have even resorted to modifying television equipment in combination with broad range amplifiers to boost signal strength (I know it's not 'tuned' to the correct frequency but I just wanted to see what would happen.). What have I learnt? With enough imagination a lot of weird and wonderful things are possible. While hooking up my wireless adapter to the home television antenna (yes, the one on the roof) prooved to be an interesting exercise it only yielded slightly better results than having no antenna at all. A broad spectrum amplification device brought it up to slightly better than the originally included 5dBi antenna and forays into using antenna systems extracted from a dead router only yielded neglible benefits. A 16dBi antenna purchased during a local swap meet did result in a noticeable (though still small) gain though. Using a sieve (it's actually quite difficult to find suitable parabolic/spherical sized shapes in the house (unless you're willing to tear up potentially valuable goods such as headlamps). I had to go out and purchase a sieve for $2.80 at a local 'value store') only helped in certain configurations (I later found out an antenna from an old eMac was actually able to significantly boost the sensitivity of the DWA-125 A3 depending on it's polarity.) unless I switched to a more forgiving Gregorian Satellite Dish design (I used another smaller sieve and some elastic bands to replicate the design).

http://en.wikipedia.org/wiki/Satellite_dish

I even tried extremely crude Cantenna and Yagi style antenna designs (I'm waiting for an order to come in). The difference was that I made mine out of solf drink bottles with the bottom cut out wrapped with aluminium foil and also something I call 'Ruler-Yagi'. Basically, an antenna that was made out of a wooden ruler (boom), gold paperclips (it's suprising what you can find these days at Officeworks), blu-tack, and connected to a wireless adapter using alligator clips. There was a significant boost in signal (50%) when my 'Softenna' was directed properly and surprisingly there was an actual gain for 'Ruler-Yagi' but once again it was only minimal (10-20% signal sensitivity increase).

In the context of cyber-intelligence/operations it interests me to see what sort of antenna systems we could possibly pursue. There is a high likelihood that given the right materials high gain antennas could be embedded or inserted inside of suit cases or even other devices with connectivity being provided via cable (or hopefully) wireless. For example, a supposedly long life battery could be modified to provide a genuinely higher gain antenna provided space/cells were cleared from the internal cavity. Alignment could be facilitated by an internal lens/reflective camera system.

- as usual thanks to all of the individuals and groups who purchase and use my goods and services
http://sites.google.com/site/dtbnguyen/
http://dtbnguyen.blogspot.com.au/

Monday, September 10, 2012

Mobile (Wireless and Power) Foo

Recently, I have had to go slightly more mobile and in doing so I've been examining both portable wireless as well as power solutons. There has been some previous work with regards to powering a netbook using a series of AA batteries in series but I've been experimenting with basically using anything I have available to me. Seeing as though I'm limiting myself to what I have though it's been interesting. Some of the battery holders that are available aren't designed to work unless they are completely populated meaning some re-wiring work is required (alligator clips) if you don't have a perfect set of batteries to fulfil your requirement (yes, I'm aware of the recommendation that you should use a balanced set of batteries but I only require the supply for a maximum of 1 minute while I switch over the actual laptop battery. Another alternative is of course using a voltage regulator/inverter.

You may be asking why I'm not just using a power inverter or a car/air laptop adapter of some sort? Well, based on what's available at my local retailers the choice isn't optimal and doesn't come in at a reasonable price. Dirty power and modified sine waves just aren't my idea of an 'ideal solution'. Hence, my foray into more flexible forms of energy. A more refined product is of course available such as the following.

http://www.batteries-depot.com/outproducts.php/24+3973

We're almost at the point where the price of solar panels, regulation, and storage have dropped (and cell efficiency has increased) such that it may be a worthwhile investment in a home (and mobile) environment. I've seen complete $200-300 options (panels, regulators, and storage pack) available at local electronics/automotive retailers of late.

Wireless technology has come a long way but it's still clear that more research is required. In some of my other work (my "Cloud and Internet Security" report is likely to exceed 600 pages now...) I've been scrutinising wireless security (and therefore long (at least 300 metres away between the source and the target with less than optimal conditions such as trees, fences, and other objects in between using both standard and inexpensive (less than $50) long range equipment. Look up Alfa wireless though there don't seem to be too many local options.) range and broad spectrum wireless options). There is still a substantial amount of Draft-N equipment (I've noticed some retailers have been clearing wireless equipment of late probably in anticipation of 802.11ac equipment. I've also noticed a trend towards merely modifying reference chips rather than seeking the most optimal performance and often manufacturers will swap chipset entirely between revisions if there are significant problems with the original release.) out there at the moment even though 802.11n was officially ratified several years ago and 802.11ac (pre-draft versions) equipment is actually on the market right now.

http://en.wikipedia.org/wiki/IEEE_802.11
http://en.wikipedia.org/wiki/IEEE_802.11n-2009

http://en.wikipedia.org/wiki/IEEE_802.11ac

http://forums.whirlpool.net.au/archive/930559

http://www.hi-techcentre.com/2012/06/09/alfa-awus036h-upgraded-to-1000mw-1w-802-11bg-high-gain-usb-wireless-long-rang-wifi-network-adapter-with-5dbi-antenna-for-wardriving-range-extension/

Based on random testing in my area it's clear that 2.4GHz wireless equipment is far more popular than 5GHz and dual band solutions are prohibitively expensive when compared with single band solutions. While MIMO has been around for a while multi-stream technology is still something we're figuring out. Three (two stream products seem to be mostly fine) stream products have only hit the market recently and research indicates that this may be due to the sheer complexity of such a setup and lack of sufficient CPU power (for a reasonable price) in a small package.

People seem to complain a lot about customer service/support these days. Based on an examination of local retailers there's very little to separate customer experiences. I have the funny feeling that if manufacturers/retailers just followed the letter of the law and provided reasonable products they would be considered the odd ones out? If you do some research you'll find that some practices border on illegality and depending on the firms in question there is a general lack of quality control and monitoring when outsourcing work.

http://www.customerservicescoreboard.com

http://www.productreview.com.au

http://www.dd-wrt.com/wiki/index.php/Supported_Devices

Prior to some of my recent antenna experimentation I thought antenna design was reasonably simple. How naive... While there are many general designs out there a lot of them undergo extensive 'tuning' and it's not immediatelly clear why they are so different from 'average antenna' designs. For example, I recently opened up a USB wireless adapter, a DWA-125 A3 (removing RF shield on a DWA-125 A3 reduced signal strength by perhaps 5% but its perceived difference in performance was negligible to be honest). It was a strange design (from my perspective) because when you ran a continuity test through it's not immediately clear that there was a distinction between ground and signal. Compare it with an examination of a Sierra 306 USB 3G (Telstra Elite 21) modem where there is a clear and distinct one to one correlation between external antenna connector and on board antenna systems (I've read that that one is for transmission and another is for reception with sometimes another option for an auxillary antenna in embedded routers solutions).

http://wireless.gumph.org/content/5/1/011-buffalo-wbrg54-insides.html
http://wireless.gumph.org/content/4/4/011-wag54g-insides.html
http://ubuntuforums.org/showthread.php?t=1263302
http://kuthulu.com/iwscanner/?module=download
http://cyb3rc0n.blogspot.com.au/2011/06/inssider-wi-fi-scanneranalyzer-for.html

http://www.nathanlipscy.com/wireless_usb_hack/

http://www.mp3car.com/hardware-development/131013-antenna-on-d-link-dwa-110-a.html
http://en.wikipedia.org/wiki/U.FL

http://www.wirelessforums.org/wireless-networking-discussion/diy-wifi-active-antenna-build-54992.html
http://www.instructables.com/id/How-to-make-an-active-wifi-tetrapak-antenna-fast/

Once you understand the concept of metamaterial antennas though it becomes clearer how they work. By altering materials you can (theoretically) increase the isolation between ground and signal providing for overall stronger signal quality and basically increase the virtual size of the antenna. Something which is not immediately obvious if you are new to miniature antenna design (I've seen some other work whch also questions this design but bypasses/improves on it by allowing for connection of higher gain conventional antenna solutions).

http://en.wikipedia.org/wiki/Metamaterial_antenna
http://en.wikipedia.org/wiki/Smart_antenna

You need to understand the theory behind the antenna in order to be able to find optimal reception whether or you will never be able to extract the optimum solution without extensive trial and error. Recently, I was fiddling around with various antenna solutions (anything that was immediately available to me from pots, pans, cans, TV antennas, to COTS solutions. Most designs/solutions are too specialised though and have too narrow a performance band. The most general wide band solution that I came across was based on parabolas and cutlery holders in a directional/perpendicular arrangemnt/setup with back panel of an dissassembled eBook Reader which had a passive cooling solution on it in the form of aluminium sheeting.) seives and other parabola like shapes with non-standard shaped USB wireless adapters. Convential orientation with the antenna (and dish like object) pointing direct at the target was significantly better (from 55 to 75% signal quality) but non-optimal than when the horizontal reference plane of the receiver was below the target and therefore the azimuth between the target and the adapter was increased (75 to 100% signal quality). Admittedly, this had partly to do with the physical objects between the adapter and the target and the interaction (absorption, reflection, superposition, and so on) between them (high school and early graduate level physics is useful here). However, if you understood how the waveform radiates from the source than you would have understood why this was a more optimal setup.

http://en.wikipedia.org/wiki/Azimuth
http://en.wikipedia.org/wiki/Diffraction

http://en.wikipedia.org/wiki/Refraction

In the context of pentration testing and network design this knowledge would also be useful in dealing with 'blind spots' and more covert access points. While there is software that can predict/simulate (within reason) wireless signal interaction with architecture and signal gain of different antenna designs in the real world this can be cumbersome. Its easier more useful if you know most of theory off the top of your head, guesttimate in the field, and then use software to confirm/more accurately determine your guesttimations.

Some serious beasts when it comes to routers out there at the moment. Power consumption similar to netbook (but with performance to match).

http://www.wikidevi.com/wiki/D-Link_DIR-835_rev_A1

http://rfshop.com.au/Articles/tabid/107/EntryId/17/Cantennas.aspx
http://rfshop.com.au/FAQ/tabid/106/language/en-AU/Default.aspx

http://www.scorptec.com.au/computer/70/510
http://www.cplonline.com.au/online-shop?page=shop.browse&category_id=211

http://www.warcom.com.au/shop/browse/antennas/
http://www.instructables.com/id/Easy-to-Build-WIFI-24GHz-Yagi-Antenna/
http://forums.whirlpool.net.au/archive/1456553
http://www.ab9il.net/wlan-projects/wifi6.html

Typical connectors for reference.

Huawei 3G - CRC9
Internal Laptop - U.FL/I.PEX
NetGear/D-Link - RP-SMA
Linksys - RP-TNC

http://www.itwire.com/your-it-news/mobility/56558-paragon-ntfs-and-hfs%20-for-android-loses-beta-status

- as usual thanks to all of the individuals and groups who purchase and use my goods and services
http://sites.google.com/site/dtbnguyen/
http://dtbnguyen.blogspot.com.au/

Tuesday, July 24, 2012

The World is Full of Software Bugs, Random Stuff, and More

It seems as though bugs may have developed an attraction to me of late. I've discovered that 'pcmanfm' doesn't handle unmounting of drives completely cleanly and that you need to manually kill processes regularly sometimes. I've also discovered that Windows Media Player (with my configuration at least) only seems to work when the TV tuner is inserted on the original USB port that it was configured on (else it will indicate that there are no tuners currently available. Obviously, you can attempt to re-configure the tuner on another USB port but that's beside the point. This is strange behaviour.). MultibootUSB needs 32-bit of 7-Zip to be installed to be run (even if you have installed the 64-bit version on a 64-bit Windows system). Otherwise, you end up with a never ending series of errors. Tip, you need to kill MultibootUSB first before killing 7-Zip else it will keep on trying to re-spawn that process.

http://www.addictivetips.com/windows-tips/multiboot-usb-installer-boot-multiple-live-linux-distros-from-a-single-usb/

While the following is not a bug I find it 'annoying'. The versions of Acronis TrueImage distributed by Seagate/Western Digital are incompatible (retail and other version are fine). I've obviously tried various Open Source options in the past but none come near the performance/compression balance that currently exists in this product and several other proprietary options.

While searching for a new external hard drive I came across the following...

http://www.phonenews.com/toshiba-acknowledges-macbook-woes-canvio-usb-3-0-hard-drives-18699/
http://www.theregister.co.uk/2012/07/23/100w_usb_power_delivery_specification/

I was recently playing around with the idea (and the practice) of turning Android phones into servers. It was not without its difficulties though. On most mobile computing devices there are forms of so called speed stepping technologies to help increase battery life. It's obviously re-appeared on Android as well but not without some of the problems that plagued other platforms. I once recall using a power control utility application on my old Android phone which underclocked it to such an extent (1/3 of it's full capacity) that I couldn't answer phone calls because there weren't enough CPU cycles for user space applications (such as unlocking the phone itself so that I could take a call) while playing music. Admittedly, the hardware specifications were minimal (it was an extremely early and inexpensive Android phone) but I would have thought a bit more thought would have gone into it prior to deployment (I 'accepted' the 'default settings' believing that that would have been adequate).

I obviously tried SSHDroid but like others I came across what were seemingly stability problems. Upon further examination though I found a lot about wireless and power control technologies. I think a lot of the problems that I was experiencing were as a consequence of power saving software (the above will likely make more sense to you now) which may have led to SSHDroid shutting down randomly and regularly. However, in my research I also came across a file transfer application called SwiFTP. In it, was option to shutdown most power saving behaviour. By enabling this, I've seen been able to achieve relatively stable connections (hours at a time).

http://f-droid.org/repository/browse/?fdid=org.swiftp&fdpage=8

You can lock up (somewhat) your Android phone by using firewall such as DroidWall.

http://f-droid.org/repository/browse/?fdid=com.googlecode.droidwall&fdpage=3

Strongly suggest you have reliable equipment if you do ANY wireless experimentation. Obviously firmware changes can have significant impacts upon devices. One thing I underestimated though was how much of an impact 'raw power' played on connection stability. In the past (and recently) I was playing around with the idea of deliberately changing architecture to maintain wireless security (as opposed to relying on pure 'Faraday Cages' and other anti-TEMPEST techniques). By using the concepts of absorption, superposition, and reflection we can manipulate wireless signal pathways (very similar to some of the techniques that are used to develop low visibility/stealth aircraft). The results of these experiments indicate that putting this theory into practice will be less trivial than I had originally anticipated though (the intensity of a signal is conversely proportional to the inverse square of the distance between the source and destination if I recall my physics correctly).

http://matt.ucc.asn.au/dropbear/dropbear.html

http://imransarwar.com/index.php/access-your-android-device-using-ssh-and-grab-apks-easily/
http://code.google.com/p/connectbot/

http://androidforums.com/android-media/20630-sleeping-droid-stops-playing-music.html

- as usual thanks to all of the individuals and groups who purchase and use my goods and services
http://sites.google.com/site/dtbnguyen/
http://dtbnguyen.blogspot.com.au/

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