Older blog entries for etbe (starting at number 922)

Receiving Death Threats

On occasion I receive death threats in comments on my blog. This doesn’t bother me, I had more than a few pathetic losers say similar things to me in high school but the difference is that a pathetic loser on the other side of the world can’t do much about it.

The latest one is on my post “Is Asperger Syndrome a Good Thing?” [1]. At 11:04AM my time (00:04 UTC) on the 23rd of November someone using IP address 82.14.50.190 (registered to “NTL Infrastructure for Tesco – Guildford”) and with the claimed email address of sharkbait @ tesco.net told me that I’m on his “to kill list“.

He was angry because my post apparently didn’t satisfy his need to “prove to people that they don’t want AS“. As it’s not possible to choose your DNA there is really no point in trying to prove that one set of genes is better than another, unless of course you want to harass people who have different genes to you.

Naturally he didn’t read my post, in fact the differences between his comment and what I wrote made me suspect that it’s something he was pasting in to lots of blogs, but it seems unlikely that he would use an iPhone for such a copy/paste job so he must just not read. For example he rhetorically asks “did you even mention it was a form of autism in your ‘negative points’” when I gave a link to the proposed DSM changes where Asperger Syndrome is being merged with “Autistic Disorder” and the word “Autism” appears 5 times in the post.

He has one specific complaint about people he knows who are on the Autism Spectrum, he says “Every time someone speaks to them they get angry and tell said person to back the fuck off. I’ve been on the receiving end.” Generally there are two possible reasons for being told to “fuck off”, one is that the person telling you is an asshole and the other is that you are being an asshole. If you are the type of person who sends death threats to bloggers then you really should consider the latter explanation.

He also suggests that I watch Boston Legal – presumably because that show has one character who is an Aspie. Now I have actually watched that show and it’s the worst legal show I’ve ever seen, when a legal show has such unrealistic portrayal of court scenes I don’t think it should be relied on for information on any other topic. I watched a couple of episodes of Boston Legal and only saw one scene with the Aspie guy, so I can’t even determine whether it’s a realistic portrayal – he’s a minor character. In any case there are plenty of Aspie guys in the Free Software community who I interact with regularly, I read forums such as AspiesForFreedom.com, and I’ve read some text books on the topic. So even if a TV show had a very accurate portrayal of an Aspie character I still doubt that I would learn anything by watching it.

As a general tip for flamers, if you want to accuse someone of being a member of a NAZI or KKK type organisation then the word you are after is Aryan not “ayrien“. If you don’t know a word then don’t use it.

Please note the conditions of sending me email [2], I reserve the right to publish all threats in any way that I wish.

A Final Note

Thanks sharkbait for adding me to your “to kill list“, I’m sure that there are lots of nice people on it and I’ve got good company.

If I didn’t get the occasional death threat I would worry that I’m not writing well enough or failing to address important issues. I will write more about Autism in the future.

Syndicated 2011-11-23 14:14:52 from etbe - Russell Coker

Galaxy S vs Xperia X10 and Android Network Access

Galaxy S Review

I’ve just been given an indefinite loan of a Samsung Galaxy S which is more useful than the Sony Ericsson Xperia X10 that I own.

I think that the main benefit is that it runs Android 2.2 instead of Android 2.1 on the Xperia. 2.2 is what gives it USB tethering support without extra software (something I haven’t tested yet but will use a lot if it works correctly) and Wifi AP support. Both phones are about the same size, the Galaxy S has slightly more RAM (reported as 304M vs 280M – which doesn’t really matter) and a lot more main storage (1.87G vs 465M usable after the OS is loaded).

The main down-sides of the Galaxy S is that it lacks a “flash“. I’m not aware of any phone camera having a proper flash, but the limited LED flash is useful for taking pictures at times and there are a variety of programs that can turn it on for use as a torch.

Also I wonder whether the Samsung people actually test their phones in real use or whether they just build them to spec. When you read the specs it sounds nice to have a phone that’s only 9.9mm thick (apart from the bulge at the bottom), but that makes it really difficult to hold. The Xperia X10 is 13mm thick and isn’t as slick so you are much less likely to drop it. I sometimes wonder whether phone companies are designing their products to be broken so that they can sell replacements.

Three Networking Sucks

My parents use 3G broadband from Three as their only connection to the Internet, this is fast enough for viewing Youtube on occasion and generally works well for them. However whenever I try to transfer any data to their system which has integrity checks it turns out to be corrupted. About every megabyte of data transferred has a corrupt packet that has a matching checksum – presumably it’s a bug in Three’s network. Because Three are desperate for customers they have given me a free 6 month subscription to a data SIM [1]. I’ve been using that SIM with my Galaxy S and found the same data corruption problem – and I’ve reproduced it in many places around Melbourne so this isn’t just one unreliable cell tower, it’s something broken in the core of the Three network.

The obvious solution to this is to use a VPN so the corrupt packets will be dropped. So I set up a PPTP VPN only to discover that it seems impossible to make the default route be via the VPN, there has been a bug report about this since 2009 – the iPhone allows configuring whether Internet traffic should go via the VPN, it can’t be that hard [2].

There is an option to use a proxy for web access, but when I tried that on Android 2.1 it only worked for the system web browser not for things like the Android Market. But there is no option for configuring a proxy for use when the VPN is active, so it doesn’t seem likely that I could run a proxy on the VPN network and direct all traffic to it.

Due to corruption on the Three network and the inability to get a VPN working correctly it seems that I can’t use the Three SIM.

Android isn’t Really Free Software

While Android implementations generally stick to the GPL and other free software licenses that are involved they seem to be a poor example of providing freedom to users.

My Xperia X10 is running Android 2.1 because Sony-Ericsson has locked the boot loader so I can’t install a newer kernel. They don’t care enough to release a new version – this is stupid of them because it means that I am much less likely to recommend their products. If Sony-Ericsson releases a newer Android release then it will be a total OS reinstall, unlike the way I can upgrade a Debian system an application at a time.

I can’t install new packages that replace system packages, so the Email and SMS programs that I’ve installed sit along side the ones that came with the system. Periodically the unwanted SMS and Email programs show up.

I can’t make my Android phones perform basic networking tasks that I’ve done on Linux systems since the early 90′s. Hiding the complexity from the newbies is OK, but they need to make the full capabilities of the system available to experts.

It seems to me that Android effectively gives the majority of users no more freedom than the iPhone does. Even for the small minority of us who are technically capable of rooting phones and installing CyanogenMod etc it’s often limited by technical measures and the amount of time required.

Update: Philipp Kern pointed out that his Galaxy S has a front facing camera. I have checked my phone and discovered that it has one too. When I published this post I criticised the Galaxy S for not having a front facing camera for video-calls based on a misunderstanding of the Wikipedia page (which says that SOME models lack it) and not testing it. Thanks for the correction Philipp and sorry for publishing wrong data.

Syndicated 2011-11-21 08:01:51 from etbe - Russell Coker

Galaxy S vs Xperia X10 and Android Network Access

Galaxy S Review

I’ve just been given an indefinite loan of a Samsung Galaxy S which is more useful than the Sony Ericsson Xperia X10 that I own.

I think that the main benefit is that it runs Android 2.2 instead of Android 2.1 on the Xperia. 2.2 is what gives it USB tethering support without extra software (something I haven’t tested yet but will use a lot if it works correctly) and Wifi AP support. Both phones are about the same size, the Galaxy S has slightly more RAM (reported as 304M vs 280M – which doesn’t really matter) and a lot more main storage (1.87G vs 465M usable after the OS is loaded).

The main down-sides of the Galaxy S are that it lacks a front facing camera (which means it can’t usefully do video-conferencing) and it lacks a “flash“. I’m not aware of any phone camera having a proper flash, but the limited LED flash is useful for taking pictures at times and there are a variety of programs that can turn it on for use as a torch.

Also I wonder whether the Samsung people actually test their phones in real use or whether they just build them to spec. When you read the specs it sounds nice to have a phone that’s only 9.9mm thick (apart from the bulge at the bottom), but that makes it really difficult to hold. The Xperia X10 is 13mm thick and isn’t as slick so you are much less likely to drop it. I sometimes wonder whether phone companies are designing their products to be broken so that they can sell replacements.

Three Networking Sucks

My parents use 3G broadband from Three as their only connection to the Internet, this is fast enough for viewing Youtube on occasion and generally works well for them. However whenever I try to transfer any data to their system which has integrity checks it turns out to be corrupted. About every megabyte of data transferred has a corrupt packet that has a matching checksum – presumably it’s a bug in Three’s network. Because Three are desperate for customers they have given me a free 6 month subscription to a data SIM [1]. I’ve been using that SIM with my Galaxy S and found the same data corruption problem – and I’ve reproduced it in many places around Melbourne so this isn’t just one unreliable cell tower, it’s something broken in the core of the Three network.

The obvious solution to this is to use a VPN so the corrupt packets will be dropped. So I set up a PPTP VPN only to discover that it seems impossible to make the default route be via the VPN, there has been a bug report about this since 2009 – the iPhone allows configuring whether Internet traffic should go via the VPN, it can’t be that hard [2].

There is an option to use a proxy for web access, but when I tried that on Android 2.1 it only worked for the system web browser not for things like the Android Market. But there is no option for configuring a proxy for use when the VPN is active, so it doesn’t seem likely that I could run a proxy on the VPN network and direct all traffic to it.

Due to corruption on the Three network and the inability to get a VPN working correctly it seems that I can’t use the Three SIM.

Android isn’t Really Free Software

While Android implementations generally stick to the GPL and other free software licenses that are involved they seem to be a poor example of providing freedom to users.

My Xperia X10 is running Android 2.1 because Sony-Ericsson has locked the boot loader so I can’t install a newer kernel. They don’t care enough to release a new version – this is stupid of them because it means that I am much less likely to recommend their products. If Sony-Ericsson releases a newer Android release then it will be a total OS reinstall, unlike the way I can upgrade a Debian system an application at a time.

I can’t install new packages that replace system packages, so the Email and SMS programs that I’ve installed sit along side the ones that came with the system. Periodically the unwanted SMS and Email programs show up.

I can’t make my Android phones perform basic networking tasks that I’ve done on Linux systems since the early 90′s. Hiding the complexity from the newbies is OK, but they need to make the full capabilities of the system available to experts.

It seems to me that Android effectively gives the majority of users no more freedom than the iPhone does. Even for the small minority of us who are technically capable of rooting phones and installing CyanogenMod etc it’s often limited by technical measures and the amount of time required.

Syndicated 2011-11-20 15:01:51 from etbe - Russell Coker

Cruises

It seems that in theory cruises can make for quite economical vacations. The cheapest prices tend to be around $100 per person per night for an “inside” cabin (IE no window) with two people (there is a significant extra fee for having a cabin with only one person). If you book a room in a half-decent hotel with a pool in some moderately desirable place then you will probably pay about $200 per night which might get you free breakfast but won’t include lunch or dinner. Cruises include all the free food you can eat for at least 16 hours of the day with maybe an extra fee for getting food in the middle of the night. When a cruise ship stops at the port you can pay for an expensive shore trip arranged by the cruise company or have a cheap trip that involves walking on the beach or taking a taxi to somewhere local. Of course there are lots of extras that can make a cruise really expensive, but if you don’t plan to eat at speciality restaurants or drink much alcohol then that shouldn’t be a problem.

I’ve just booked a short luxury cruise, mostly as a trial of the cruise concept. The process of doing so was difficult enough that even if I hadn’t previously needed a holiday then I’d probably need one now. It would be interesting to compare the amount of time that a reasonable person would be likely to spend choosing a holiday and purchasing it for the different types of holiday, I expect that cruising would be a long way behind everything that involves flying to a foreign city and staying in a hotel.

The Issues of Booking

When booking a regular holiday you choose where to visit, then choose the time of year, the accommodation, and travel. While the order can vary it’s generally a sequential process without too many variables at any stage.

With a cruise one of the first decisions is to choose the cruise line, different lines cater to various market segments – it’s clear what Disney cruises aim for but often not so clear for others. Apart from Disney the other cruise lines don’t seem to make clear statements about who they are and aren’t targeting. Then there are a variety of ships run by each cruise line which in many cases offer different features, do you want 1 pool or 4? Do you want ice skating? The cruise lines that I have investigated don’t offer clear comparisons of their ships. As a cruise ship is essentially a hotel, a collection of restaurants, and some other entertainment you can’t just arbitrarily choose one the way you might choose a random hotel with a suitable price and rating.

Now while you can choose a hotel and generally get a room when you want a cruise booking has to be made when the ship is in a convenient port. So your holiday needs to be scheduled around the availability of the ship. CruiseCritic.com is an excellent source of information on cruises and has a very active and useful advice forum [1]. The forum appears to be dominated by retirees, presumably because retirees have time to just wait for a ship they like to visit their local port while people who have to schedule holidays around work projects etc.

When booking a hotel I have found that Wotif.com is really good for comparing hotels and finding a reasonably cheap one and they also have periodic mail-outs about special deals. I have made a couple of short vacations based on Wotif offering me unusually good prices on a hotel in a place that I was mildly interested in visiting. There are also special deals on cruises, but it’s a lot more difficult to take them. Firstly as cruises aren’t as interchangeable as hotels it’s not as appealing to take an offer of a cruise you didn’t previously consider because it’s going cheap. The second factor is that according to cruise reviews there is more variation among cabins than there is among hotel rooms. The design of the ship that is needed to cram everything in the available space means that some cabins apparently have noise pollution from various activities on the ship while others are considered to have problems for people prone to sea-sickness. Discounts probably only apply after people who pay non-discount rates have had a chance to book what might be considered the better cabins. Of course it could be a good thing to have most of the ship booked out, CruiseCritic.com has some reviews of individual cabins and presumably there are people who compare hundreds of cabins to discover what is ideal for them.

The Problem with Princess

I have booked a Princess cruise. I chose it because it was going cheap, but the first two travel agents that advertised it were unable to take my order because Princess only allows US based agencies (which means the discount agents on the net) to sell to US customers – I don’t think that the people who run the Princess cruise company know what the Internet is about.

So I booked the cruise through the Princess web site, they took my money, told me that a good chunk of that money would never be returned if I cancelled, and then sent me to the web page for providing all the information that they need – which is a lot. The big problem was when their web site absolutely demanded a passport number and said that I would not be allowed to board without one even though their FAQ (and common sense) indicated that a cruise which doesn’t involve any international travel has no need of a passport. Taking someone’s money and then telling them that they can’t attend due to not having a valid passport is one way of making a future passenger very unhappy.

I called the support people (which was Carnival) and had to listen to some really strange hold music – it was difficult to determine if the music was produced by someone with unusual tastes in electronic music vastly different from my own preference or whether the computer which manages the phone calls was producing noise instead of music. Eventually I got through to an operator who was very helpful and stored my drivers’ license number which was adequate.

While on the topic of their web site, when booking a cruise with Princess they list which types of cabin (interior, balcony, etc) are available and list the price for the cheapest category of cabin in each price. However if the cheapest category is all sold out then it will still list that cheapest price and thus be advertising a price that can’t be booked. This is misleading and annoying.

Further Hassle

But the difficulty doesn’t end here. On a cruise you have to book in advance for which dinner seating you desire – which is usually only early or late but some ships offer “anytime”. Then if you happen to be travelling with people who are in a separate cabin and paying separately (which one would expect to be fairly common) there is no obvious way of synchronising dinner preferences – the ship people might assign people to different tables. I admit that I haven’t fully explored the post-booking part of the Princess web site, maybe I can arrange a shared table – but for the moment my pain threshold for the cruise booking process has been exceeded.

Other Cruising Stuff

Insight Cruises (formerly Geek Cruises) offers a variety of educational cruises including science, astronomy, chess, art, history, and some other things [2]. From a casual inspection of their web site it seems that the cruise prices are around $300 per night for a 2 person cabin and the registration fees for the conferences are between $1200 and $1500. Most readers of my blog will consider this to be unreasonably expensive as registration for a Linux conference tends to be a lot less than $1000. But when compared to typical for-profit conferences $1500 isn’t anywhere near the high end of the range. Also while someone who is choosing a cruise holiday can easily get a cruise that costs less than $200 per day for a 2 person cabin, for commercial conferences it’s not uncommon to spend more than $300 per night for two people on accommodation and food. So the only noteworthy part about the cost is that accommodation will be quite expensive if you aren’t sharing a room.

If you want to run a conference on a cruise there are companies which specialise in such things, Landry and Kling is one company that specialises in planning corporate events [3]. They do seem to aim for the high end of the market, including chartering a small cruise ship or half a large cruise ship – that means ~1000 passengers. While there are some conferences with more than 1000 delegates it seems that most conferences top out at about 500 delegates. However I know that some conferences have limited the number of delegates to the maximum capacity of the biggest lecture hall available – as some cruise ships have a theater with more than 1000 seats it seems that similar conferences could potentially arrange a half ship charter. A half ship charter apparently allows exclusive access to one of the theaters (at least when it’s not needed for evening entertainment) and exclusive seating at the main dining room. It’s a standard feature that cruise ships have all the equipment you might need to run a conference.

Autism on the Seas is a brand used by the Alumni Cruise company for their holiday packages for special needs children [4]. They sell cruise tickets at the regular list price and the commission that they receive when acting as a travel agency is enough to hire staff to look after the kids while presumably still running at a profit. It seems to me that a similar model could be used for a computer conference, make a profit on cruise ticket sales and then have no extra costs for the conference – for people sharing a room that would be cheaper than most Linux conferences I’ve attended.

For smaller conferences and un-conferences there is no minimum reservation size. One down-side for a computer conference is the cost of Internet access, according to Wikipedia a personal installation of satellite net access costs $5 per megabyte and ship pricing for their Internet access is up around $30-$100 per hour per person! But in the old days when attending a conference meant a week of no net access we survived somehow.

It also seems to me that if a company had a small development team it could be productive to put everyone on a cruise ship with a server for testing and version control. They could do 9 hour days on board and still have lots of time for relaxation as it’s only a few minutes walk to the pool. Of course this wouldn’t work if some members of the team wanted to stay home due to slow and expensive net access.

Syndicated 2011-11-17 07:32:09 from etbe - Russell Coker

Good Riddance to Flash

The Age reports that Adobe has ceased development of Flash for mobile systems [1]. This is described as leading to an improvement in the web experience for iPhone and iPad users, but the more important thing is that it will improve the experience for everyone. The Flash plugin has always been a resource hog and has never been properly supported on all the common platforms. Also most sites that use Flash never needed to as there were other ways of getting equal or better results without it.

Now that Flash is officially on the path to obsolescence everyone can move to HTML5.

I use the following configuration directives in my Squid configuration to block Flash, I selectively enable Flash for the few web sites which use it for useful things. Blocking flash in this manner means that desktop systems which have the Flash plugin installed probably won’t be vulnerable to Flash security flaws as it is unlikely that one of the few sites that I permit to send Flash to my network would end up hosting hostile Flash code.

acl swf url_regex swf$ swf\?
acl swftype req_mime_type -i ^application/x-shockwave-flash$
http_access deny swf
http_access deny swftype

Wikipedia has a comparison of HTML5 and Flash. One interesting benefit that is claimed for Flash is that it allows DRM and it supports inserting commercials and in other ways giving the user an experience that they don’t want. It seems that to put some more nails in the Flash coffin we need tools to suck video from Flash sites regardless of DRM and which skip commercials.

Syndicated 2011-11-12 11:34:58 from etbe - Russell Coker

SE Linux Status in Debian 2011-10

Debian/Unstable Development

deb http://www.coker.com.au wheezy selinux

The above APT sources.list line has my repository for SE Linux packages that have been uploaded to Unstable and which will eventually go to testing and then the Wheezy release (if they aren’t obsoleted first). I have created that repository for people who want to track SE Linux development without waiting for an Unstable mirror to update.

In that repository I’ve included a new version of policycoreutils that now includes mcstrans and also has support for newer policy such that the latest selinux-policy-default package can be installed. The version that is currently in Testing supports upgrading policy on a running system but doesn’t support installing the policy on a system that previously didn’t run SE Linux.

I have also uploaded SE Linux Policy packages from upstream release 20110726 compared to the previous packages which were from upstream release 20100524. As the numbers imply there is 14 months of upstream policy development which changes many things. Many of the patches from my Squeeze policy packages are not yet incorporated in the policy I have uploaded to Unstable. I won’t guarantee that an Unstable system in Enforcing mode will do anything other than boot up and allow you to login via ssh. It’s definitely not ready for production but it’s also very suitable for development (10 years ago I did a lot of development on SE Linux systems that often denied login access, it wasn’t fun).

Kyle Moffett submitted a patch for libselinux which dramatically changed the build process. As Manoj (who wrote the previous build scripts) was not contactable I accepted Kyle’s patch as provided. Thanks for the patch Kyle, and thanks for all your work over the years Manoj. Anyway the result of these changes should mean that it’s easier to bootstrap Debian on a new architecture and easier to support multi-arch – but I haven’t tested either of these.

Squeeze

The policy packages from Squeeze can’t be compiled on Unstable. The newer policy compilation tool chain is more strict about how some things can be declared and used, thus some policy which was fairly dubious but usable is now invalid. While it wouldn’t be difficult to fix those problems I don’t plan to do so. There is no good reason for compiling Squeeze policy on Unstable now that I’ve uploaded a new upstream release.

deb http://www.coker.com.au squeeze selinux

I am still developing Squeeze policy and releasing it in the above APT repository. I will also get another policy release in a Squeeze update if possible to smooth the transition to Wheezy – the goal is that Squeeze policy will be usable on Wheezy even if it can’t be compiled. Also note that the compilation failures only affect the Debian package, it should still be possible to make modules for local use on a Wheezy system with Squeeze policy.

MLS

On Wednesday I’m giving a lecture at my local LUG about MLS on SE Linux. I hope to have a MLS demonstration system available to LUG members by then. Ideally I will have a MLS system running on a virtual server somewhere that’s accessible as well as a Xen/KVM image on a USB stick that can be copied by anyone at the meeting.

I don’t expect to spend much time on any aspect of SE Linux unrelated to MLS for the rest of the week.

Version Control

I need to change the way that I develop SE Linux packages, particularly the refpolicy source package (source of selinux-policy-default among others). A 20,000 line single patch is difficult to work with! I will have to switch to using quilt, once I get it working well it should save me time on my own development as well as making it easier to send patches upstream. Also I need to setup a public version control system so I can access the source from my workstation, laptop, and netbook. While doing that I might as well make it public so any interested people can help out. Suggestions on what type of VCS to use are welcome.

How You Can Help

Sorting out the mess that is the refpolicy package, sending patches upstream and migrating to a VCS is a fair bit of work. But there are lots of small parts. Sending patches upstream is a job that could be done in small pieces.

Writing new policy is not something to do yet. There’s not much point in doing that while I still haven’t merged all the patches from Squeeze – maybe next week. However I can provide the missing patches to anyone who wants to review them and assist with the merging.

I have a virtual server that has some spare capacity. One thing I would like to do is to have some virtual machines running Unstable with various configurations of server software. Then we could track Unstable on those images and use automated testing to ensure that nothing breaks. If anyone wants root access on a virtual server to install their favorite software then let me know. But such software needs to be maintained and tested!

Syndicated 2011-10-31 12:22:43 from etbe - Russell Coker

Links October 2011

Ron has written an interesting blog post about the US as a “lottery economy” [1]. Most people won’t win the lottery (literally or metaphorically) so they remain destined for poverty.

Tim Connors wrote an informative summary of the issues relating to traffic light timing and pedestrians/cyclists [2]. I have walked between Southgate and the Crown Casino area many times and have experienced the problem he describes many times.

Scientific American has an interesting article about a new global marketplace for scientific research [3]. The concept is that instead of buying a wide range of research equipment (and hiring people to run it) you can outsource non-core research for a lower cost.

Svante Pääbo gave an interesting TED talk about his work analysing human DNA to determine prehistoric human migration patterns [4]. Among other things he determined that 2.5% of the DNA from modern people outside Africa came from the Neandertals.

Lisa wrote an informative article about Emotional Support Animals (as opposed to Service Animals such as guide dogs) for disabled people [5]. It seems that the US law is quite similar to Australian law in that “reasonable accommodations” have to be made for disabled people which includes allowing pets in rental properties – even if such pets aren’t officially ESAs.

Beyond Zero Emissions has an interesting article about electricity prices which explains how wind power forces prices down [6]. This should offset the new “carbon tax”.

Problogger has an article listing some of the ways that infographics can be used on the web [7]. This can be for blog posts or just for your personal understanding.

Petter Reinholdtsen wrote a handy post about ripping DVDs which also explains how to do it when the DVD has errors [8], I haven’t yet ripped a DVD but this one is worth noting for when I do.

Miriam has written about the “Fantastic Park” ICT training for 8-12yo kids [9]. It’s run in Spain (and all the links are in Spanish – but Google Translation works well) and is a camp to teach children about computers and robotics using Lego Wedo among other things. We need to have more of these things in other countries.

The Atlantic Cities has an interesting article comparing grid and cul-de-sac based urban designs [10]. Apparently the cul-de-sac design forces an increase in car use and therefore an increase in fatal accidents while also decreasing the health benefits of walking. Having lived in both grid and cul-de-sac based urban areas I have personally experienced the benefits of the grid based layout.

Sarah Chayes wrote an interesting LA Times article about governments being taken over by corruption [11]. She argues that arbitrary criminal government leads to an increase in religious fundamentelism.

Michael Lewis has an insightful article in Vanity Fair about the bankruptcy of US states and cities [12].

Ben Goldacre gave an interesting TED talk about bad medical science [13]. He starts with the quackery that is published in tabloid newspapers and then moves on to deliberate scientific fraud by medical companies.

Geoff Mulgan gave an interesting TED talk about the Studio Schools in the UK which are based around group project work [14]. The main thing I took from this is that the best method of teaching varies by subject and by student. So instead of having a monolithic education department controlling everything we should have schools aimed at particular career paths and learning methods.

Sophos has an interesting article about the motion sensors of smart phones being used to transcribe keyboard input based on vibration [15]. This attack could be launched by convincing a target to install a trojan application on their phone. It’s probably best to regard your phone with suspicion nowadays.

Simon Josefsson wrote a good article explaining how to use a GPG smart-card to authenticate ssh sessions with particular reference to running backups over ssh [16].

Cùran wrote a good article explaining how to use all the screen space when playing DVDs on a wide screen display with mplayer [17].

Charles Stross has an informative blog post about Wall St Journal circulation fraud [18]. Apparently the WSJ was faking readership numbers to get more money from advertisers, this should lead to law suits and more problems for Rupert Murdoch. Is everything associated with Wall St corrupt?

Syndicated 2011-10-31 01:47:10 from etbe - Russell Coker

Desktop Equivalent Augmented Reality

Augmented reality is available on all relatively modern smart phones. I’ve played with it on my Android phone but it hasn’t delivered the benefits that I hoped, there is a game where you can walk through a virtual maze which didn’t work for me, and a bunch of programs which show me the position of stars, pizza restaurants, and other things which are cool but not really useful.

It has been proven that larger screen size can make a surprising difference in productivity for increasing monitor size. The general concept seems to be that ideally everything you are thinking about at one time should be on the screen at once. I’m not aware of any research comparing phones to desktop monitors but it is obvious that some tasks become extremely difficult or nearly impossible when attempted on the tiny screen of a phone. One significant example is coding. One noteworthy thing about coding is that the amount of typing is often quite small when compared to the amount of time spent looking at code, so the lack of good keyboard options on phones isn’t always a serious problem.

The iPhone 4 has a resolution of 640*960 which seems to be the best available phone resolution (with 480*854 being the highest resolution that is available in many phones). The Dell Streak at 5 inches seemed to have the largest screen in a phone, but they have stopped selling them. It seems that the largest screen available in a phone is about 4.2 inches. Probably the minimum that would be considered usable for development would be a resolution of about 1280*1024 and a screen size of about 14 inches, while opinion will vary a lot about this I think that the vast majority of programmers will agree that the bigger tablet computers and Netbooks (at about 10 inches and something like 1366*768 resolution) are well below the minimum size.

It seems to me that a possible solution to this problem involves using augmented reality to provide a virtual desktop that is significantly larger and which has a significantly higher resolution. The advantage of augmented reality over merely scrolling is that it should allow faster and more reliable seeking for the section of virtual desktop that is of interest, and seek speed is probably the bottleneck with small monitors. One problem for this would be turning corners when on public transport, but the camera button could be used to reset the current phone position to be the middle of the viewing area, if the process of resetting the angle is fast enough it wouldn’t be a great distraction.

I don’t think that a mobile phone will ever be a great device for software development and I don’t think that the places where a serious computer isn’t available are good places to work. But sometimes I get inspiration for tracking down a difficult bug when on the move and it would be really good to be able to read the code immediately.

I won’t have any time to work on such things myself. I’m just publishing the idea in case someone who likes it happens to have a lot of spare time…

Syndicated 2011-10-28 11:19:07 from etbe - Russell Coker

Capabilities vs SE Linux

In December 2010 a paper was published by Robert N.M. Watson and Jonathan Anderson from the Cambridge University and Ben Laurie and Kris Kennaway of Google about the Capsicum capabilities system [1]. It seems that the aim of the project is to allow systems that need privileges briefly when they start (such as tcpdump) a safe method of dropping privs. The main project page is here [2].

The focus of the paper is on the Chromium web browser and six different ways of constraining the Chromium sandbox are compared. For the SE Linux comparison they claim 200 lines of code changes as of Fedora 15, in Fedora 16 I couldn’t find a Chromium package, so I presume that they mean 200 lines of SE Linux policy (I am not aware of anyone modifying the Chromium source for SE Linux). They note that SE Linux doesn’t support separating different sandboxes, while it would be possible to have each sandbox be assigned a different MCS sensitivity label to separate them that option would be unwieldy enough that they are essentially correct in this regard. For SE Linux systems running the MLS policy the correct thing to do would be to run multiple copies of Chromium at different levels to access different sensitivity levels of data, this would normally be done by polyinstantiating the home directory.

One thing to note however is that there is no requirement that only one security method be implemented. I can’t think of any technical reason why it would be impossible to run SE Linux and Capsicum on the same system. SE Linux could constrain daemons and restrict the access to Capsicum services while Capsicum could be used to give minimum privileges to parts of Chromium. I’m not sure that such a combination would offer anything that the MLS users would desire, but it seems that everyone else (the vast majority of computer users) would be served well by a combination of SE Linux and Capsicum.

It’s disappointing that the paper didn’t mention Posix 1003.1e capabilities, but given the lack of use that Posix capabilities get that’s understandable.

It’s also disappointing when someone develops something new and different nowadays and doesn’t provide a virtual machine image for it. Installing and configuring something that requires application and kernel changes is a lot of work and most people who are idly curious about the technology won’t go to the effort. By today’s standards it’s not that difficult to share a 1GB filesystem image via Bittorrent.

Syndicated 2011-10-28 02:47:57 from etbe - Russell Coker

Dual SIM Phones vs Amaysim vs Contract for Mobile Phones

Currently Dick Smith is offering two dual-SIM mobile phones for sale in Australia. One is the LG T510 for $99, but it only supports GSM on each SIM. This might be a good phone for someone who needs to receive both work and personal calls and doesn’t want to carry two phones, but the lack of 3G support is a major limit on what can be done with the phone.

The other phone is the Huawei U8520 which supports 3G on one SIM and GSM on the other. It costs $249, runs Android 2.2, has a 320*480 display, and a 3.2 megapixel camera. For comparison the LG Optimus One is a single-SIM phone with similar specs that only costs $179 from TeleChoice, so there is a 40% price premium to pay for a dual-SIM phone.

When I first heard about dual-SIM phones (before they were commonly and cheaply available in Australia) I had thought that it would be a good option for using a cheap 3G broadband SIM along with a SIM for voice calls from one of the cheaper pre-paid mobile companies. But the helpful guy at Dick Smith informed me that Amaysim offers good pre-paid deals for voice and data [1]. With 10G of data quota to be used in one year for $100 and reasonable rates on voice calls it should be easy to keep under $200 per annum if you don’t use many calls.

Rene Cunningham has described how to use a pre-paid data-only plan on the Optus network with VOIP for most outbound calls [2]. To do that he is paying $30 every 6 months to keep his old number for inbound calls for which he gets $30 of credit, with Amaysim you can pay $10 every 3 months to get the same result with $40 per annum call cost instead of $60. As Amaysim are on the Optus network the result should be the same as long as Amaysim have enough capacity for IP data transfer. Rene uses an iPhone but the same result can be achieved with an Android phone.

If by using VOIP the cost of running a phone on Amaysim was reduced to something like $160 per annum (with a possibly optimistic aim of $20 per annum for outbound VOIP calls) then over two years that could save $376 over a $29 per month contract. A Virgin $29 contract includes a Sony Ericsson Xperia X10 which is a fairly nice phone if you can deal with the short battery life and the fact that it’s locked to Android 2.1. An Xperia X10 can be bought on Ebay for less than $376 but the hassle of setting up VOIP and Amaysim will be more effort than it’s worth to save $100 over two years.

A couple of my relatives have phone contracts that are about to expire. I’m not going to set them up on VOIP as it’s too much effort for too little benefit and the dual-SIM phone really isn’t an option. I will recommend Virgin contracts with Xperia X10 phones or Amaysim with their existing phones (2yo smart phones that are still quite usable).

Syndicated 2011-10-27 10:47:21 from etbe - Russell Coker

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