Older blog entries for etbe (starting at number 1056)

Noise from Shaving

About 10 years ago I started using an electric shaver. An electric shaver is more convenient to use as it doesn’t require any soap, foam, or water. It is also almost impossible to cut yourself properly with an electric shaver which is a major benefit for anyone who’s not particularly alert in the morning. Generally my experience of electric shavers has been good, although the noise is quite annoying.

Recently a friend told me that an electric shaver is as noisy as a chain-saw. Given the inverse-square law and the fact that the shaver operates within 1cm of my ears that sounds plausible. So the risk of hearing loss is a great concern. Disposable ear plugs are very cheap and they can be used multiple times (they don’t get particularly dirty while shaving or get squashed in the short time needed to shave). So for a few weeks I’ve been using ear plugs while shaving which reduces the noise and presumable saves me from some hearing damage – although after 10 years of using electric shavers I may have already sustained some damage.

According to Cooper Safety their ear plugs reduce noise by 29dB, [1] I presume that the cheap ones I bought from Bunnings would be good for at least 15dB.

According to Better Hearing Sydney the noise from an electric shaver is typically around 90dB, less than the 100dB that is typical of a chain-saw [2]. So if my ear-plugs are good for 15dB then they would reduce the noise from a typical electric shaver to 75dB which is well below the 85dB that will cause hearing damage. Given that the noise from a typical shaver is only slightly above the damage threshold it seems that I might not need particularly good ear-plugs when shaving.

A quick scan of shaver reviews indicates that the amount of noise differs by brand and technology. The Hubpages review suggests that rotary shavers tend to make less noise than foil shavers [3], but I’m sure that it varies enough between brands that some rotary shavers are louder than the quietest foil shavers. It seems that the best thing to do when buying a new shaver would be to go to a specialised shaver shop (which has many models on offer) and get the staff to demonstrate them to determine which is the quietest. If a typical shaver produces 90dB then it seems likely that one of the more quiet models would produce less than 85dB.

Another item on my todo list is to buy a noise meter to measure the amount of noise produced in the places where I spend time. There are some Android apps to measure noise, I’m currently playing with the Smart Tools Co Sound Meter [4] which gives some interesting information. The documentation notes that phone microphones are limited to the typical volume and frequencies of human voice, so my Galaxy S3 can’t measure anything about 81dB. My wife’s Nexus 4 doesn’t seem to register anything above 74dB. Additionally there is some uncertainty about the accuracy of the microphone, there is a calibration feature but that requires another meter. Anyway the Sound Meter app suggests that my shaver (a Philips HQ7380/B) produces only 71dB at the closest possible range – and drops down to 67dB at the range I would use if I grew sideburns.

Conclusion

Getting a proper noise meter to protect one’s hearing seems like a good idea. An Android app for measuring noise is a good thing to have, even though it’s not going to be accurate it’s convenient and will give an indication.

When buying a shaver one should listen to all the options and choose a quiet one (I might have got a quiet one by luck).

Sideburns seem like a good idea if you value your hearing.

• [1] http://www.coopersafety.com/NoiseReduction.aspx
• [2] http://www.betterhearingsydney.org.au/content/view/46/53/
• [3] http://tinyurl.com/ojxfx9t
• [4] https://play.google.com/store/apps/details?id=kr.sira.sound

Syndicated 2013-05-23 09:56:22 from etbe - Russell Coker

No Backups WTF

Some years ago I was working on a project that involved a database cluster of two Sun E6500 servers that were fairly well loaded. I believe that the overall price was several million pounds. It’s the type of expensive system where it would make sense to spend adequately to do things properly in all ways.

The first interesting thing was the data center where it was running. The front door had a uniformed security guard and a sign threatening immediate dismissal for anyone who left the security door open. The back door was wide open for the benefit of the electricians who were working there. Presumably anyone who had wanted to steal some servers could have gone to the back door and asked the electricians for assistance in removing them.

The system was poorly tested. My colleagues thought that with big important servers you shouldn’t risk damage by rebooting them. My opinion has always been that rebooting a cluster should be part of standard testing and that it’s especially important with clusters which have more interesting boot sequences. But I lost the vote and there was no testing of rebooting.

Along the way there were a number of WTFs in that project. One of which was when the web developers decided to force all users to install the latest beta release of Internet Explorer, a decision that was only revoked when the IE install process broke MS-Office on the PC of a senior manager. Another was putting systems with a default Solaris installation live on the Internet with all default services running, there’s never a reason for a database server to be directly accessible over the Internet.

No Backups At All

But I think that the most significant failing was the decision not to make any backups. This wasn’t merely forgetting to make backups, when I raised the issue I received a negative reaction from almost everyone. As an aside I find it particularly annoying when someone implies that I want backups because I am likely to stuff things up.

There are many ways of proving that there’s a general lack of competence in the computer industry. But I think that one of the best is the number of projects where the person who wants backups has their competence questioned instead of all the people who don’t want backups.

A decision to make no backups relies on one of two conditions, either the service has to be entirely unimportant or you need to have no bugs in the OS or hardware defects that can corrupt data, no application bugs, and a team of sysadmins who never make mistakes. The former condition raises the question of why the service is being run and the latter is impossible.

As I’m more persistent than most people I kept raising the issue via email and adding more people to the CC list until I got a positive reaction. Eventually I CC’d someone who responded with “What the fuck” which I consider to be a reasonable response to a huge and expensive project with no backups. However the managers on the CC list regarded the use of profanity in email to be a much more serious problem. To the best of my knowledge there were never any backups of that system but the policy on email was strongly enforced.

This is only a partial list of WTF incidents that assisted in my decision to leave the UK and migrate to the Netherlands.

Not Doing Much

About a year after leaving I returned to London for a holiday and had dinner with a former colleague. When I asked what he was working on he said “Not much“. It turned out that proximity to the nearest manager determined the amount of work that was assigned. As his desk was a long way from the nearest manager he had spent about 6 months getting paid to read Usenet. That wasn’t really a surprise given my observations of the company in question.

Syndicated 2013-05-21 09:43:37 from etbe - Russell Coker

Advice on Buying a PC

A common topic of discussion on computer users’ group mailing lists is advice on buying a PC. I think that most of the offered advice isn’t particularly useful with an excessive focus on building or upgrading PCs and on getting the latest and greatest. So I’ll blog about it instead of getting involved in more mailing-list debates.

A Historical Perspective – the PC as an Investment

In the late 80′s a reasonably high-end white-box PC cost a bit over $5,000 in Australia (or about $4,000 without a monitor). That was cheaper than name-brand PCs which cost upwards of $7,000 but was still a lot of money. $5,000 in 1988 would be comparable to $10,000 in today’s money. That made a PC a rather expensive item which needed to be preserved. There weren’t a lot of people who could just discard such an investment so a lot of thought was given to upgrading a PC.

Now a quite powerful desktop PC can be purchased for a bit under $400 (maybe $550 if you include a good monitor) and a nice laptop is about the same price as a desktop PC and monitor. Laptops are almost impossible to upgrade apart from adding more RAM or storage but hardly anyone cares because they are so cheap. Desktop PCs can be upgraded in some ways but most people don’t bother apart from RAM, storage, and sometimes a new video card.

If you have the skill required to successfully replace a CPU or motherboard then your time is probably worth enough that getting more value out of a PC that was worth $400 when new and is worth maybe $100 when it’s a couple of years old probably isn’t a good investment.

Times have changed and PCs just aren’t worth enough to be bothered upgrading. A PC is a disposable item not an investment.

Buying Something Expensive?

There are a range of things that you can buy. You can spend $200 on a second-hand PC that’s a couple of years old, $400 on a new PC that’s OK but not really fast, or you can spend $1000 or more on a very high end PC. The $1000 PC will probably perform poorly when compared to a PC that sells for $400 next year. The $400 PC will probably perform poorly when compared to the second-hand systems that are available next year.

If you spend more money to get a faster PC then you are only getting a faster PC for a year until newer cheaper systems enter the market.

As newer and better hardware is continually being released at low enough prices that make upgrades a bad deal I recommend just not buying expensive systems. For my own use I find that e-waste is a good source of hardware. If I couldn’t do that then I’d buy from an auction site that specialises in corporate sales, they have some nice name-brand systems in good condition at low prices.

One thing to note is that this is more difficult for Windows users due to “anti-piracy” features. With recent versions of Windows you can’t just put an old hard drive in a new PC and have it work. So the case for buying faster hardware is stronger for Windows than for Linux.

That said, $1,000 isn’t a lot of money. So spending more money for a high-end system isn’t necessarily a big deal. But we should keep in mind that it’s just a matter of getting a certain level of performance a year before it is available in cheaper systems. Getting a $1,000 high-end system instead of a $400 cheap system means getting that level of performance maybe a year earlier and therefore at a price premium of maybe $2 per day. I’m sure that most people spend more than $2 per day on more frivolous things than a faster PC.

Understanding How a Computer Works

As so many things are run by computers I believe that everyone should have some basic knowledge about how computers work. But a basic knowledge of computer architecture isn’t required when selecting parts to assemble to make a system, one can know all about selecting a CPU and motherboard to match without understanding what a CPU does (apart from a vague idea that it’s something to do with calculations). Also one can have a good knowledge of how computers work without knowing anything about the part numbers that could be assembled to make a working system.

If someone wants to learn about the various parts on sale then sites such as Tom’s Hardware [1] provide a lot of good information that allows people to learn without the risk of damaging expensive parts. In fact the people who work for Tom’s Hardware frequently test parts to destruction for the education and entertainment of readers.

But anyone who wants to understand computers would be better off spending their time using any old PC to read Wikipedia pages on the topic instead of spending their time and money assembling one PC. To learn about the basics of computer operation the Wikipedia page for “CPU” is a good place to start. Then the Wikipedia page for “hard drive” is a good start for learning about storage and the Wikipedia page for Graphics Processing Unit to learn about graphics processing. Anyone who reads those three pages as well as a selection of pages that they link to will learn a lot more than they could ever learn by assembling a PC. Of course there’s lots of other things to learn about computers but Wikipedia has pages for every topic you can imagine.

I think that the argument that people should assemble PCs to understand how they work was not well supported in 1990 and ceased to be accurate once Wikipedia became popular and well populated.

Getting a Quality System

There are a lot of arguments about quality and reliability, most without any supporting data. I believe that a system designed and manufactured by a company such as HP, Lenovo, NEC, Dell, etc is likely to be more reliable than a collection of parts uniquely assembled by a home user – but I admit to a lack of data to support this belief.

One thing that is clear however is the fact that ECC RAM can make a significant difference to system reliability as many types of error (including power problems) show up as corrupted memory. The cheapest Dell PowerEdge server (which has ECC RAM) is advertised at $699 so it’s not a feature that’s out of reach of regular users.

I think that anyone who makes claims about PC reliability and fails to mention the benefits of ECC RAM (as used in Dell PowerEdge tower systems, Dell Precision workstations, and HP XW workstations among others) hasn’t properly considered their advice.

Also when discussing overall reliability the use of RAID storage and a good backup scheme should be considered. Good backups can do more to save your data than anything else.

Conclusion

I think it’s best to use a system with ECC RAM as a file server. Make good backups. Use ZFS (in future BTRFS) for file storage so that data doesn’t get corrupted on disk. Use reasonably cheap systems as workstations and replace them when they become too old.

Update: I find it rather ironic when a discussion about advice on buying a PC gets significant input from people who are well paid for computer work. It doesn’t take long for such a discussion to take enough time that the people involved could spent their time working instead, put enough money in a hat to buy a new PC for the user in question, and still had money left over.

• [1] http://www.tomshardware.com/

Syndicated 2013-05-21 04:58:03 from etbe - Russell Coker

Advice on Buying a PC

A common topic of discussion on computer users’ group mailing lists is advice on buying a PC. I think that most of the offered advice isn’t particularly useful with an excessive focus on building or upgrading PCs and on getting the latest and greatest. So I’ll blog about it instead of getting involved in more mailing-list debates.

A Historical Perspective – the PC as an Investment

In the late 80′s a reasonably high-end white-box PC cost a bit over $5,000 in Australia (or about $4,000 without a monitor). That was cheaper than name-brand PCs which cost upwards of $7,000 but was still a lot of money. $5,000 in 1988 would be comparable to $10,000 in today’s money. That made a PC a rather expensive item which needed to be preserved. There weren’t a lot of people who could just discard such an investment so a lot of thought was given to upgrading a PC.

Now a quite powerful desktop PC can be purchased for a bit under $400 (maybe $550 if you include a good monitor) and a nice laptop is about the same price as a desktop PC and monitor. Laptops are almost impossible to upgrade apart from adding more RAM or storage but hardly anyone cares because they are so cheap. Desktop PCs can be upgraded in some ways but most people don’t bother apart from RAM, storage, and sometimes a new video card.

If you have the skill required to successfully replace a CPU or motherboard then your time is probably worth enough that getting more value out of a PC that was worth $400 when new and is worth maybe $100 when it’s a couple of years old probably isn’t a good investment.

Times have changed and PCs just aren’t worth enough to be bothered upgrading. A PC is a disposable item not an investment.

Buying Something Expensive?

There are a range of things that you can buy. You can spend $200 on a second-hand PC that’s a couple of years old, $400 on a new PC that’s OK but not really fast, or you can spend $1000 or more on a very high end PC. The $1000 PC will probably perform poorly when compared to a PC that sells for $400 next year. The $400 PC will probably perform poorly when compared to the second-hand systems that are available next year.

If you spend more money to get a faster PC then you are only getting a faster PC for a year until newer cheaper systems enter the market.

As newer and better hardware is continually being released at low enough prices that make upgrades a bad deal I recommend just not buying expensive systems. For my own use I find that e-waste is a good source of hardware. If I couldn’t do that then I’d buy from an auction site that specialises in corporate sales, they have some nice name-brand systems in good condition at low prices.

One thing to note is that this is more difficult for Windows users due to “anti-piracy” features. With recent versions of Windows you can’t just put an old hard drive in a new PC and have it work. So the case for buying faster hardware is stronger for Windows than for Linux.

That said, $1,000 isn’t a lot of money. So spending more money for a high-end system isn’t necessarily a big deal. But we should keep in mind that it’s just a matter of getting a certain level of performance a year before it is available in cheaper systems. Getting a $1,000 high-end system instead of a $400 cheap system means getting that level of performance maybe a year earlier and therefore at a price premium of maybe $2 per day. I’m sure that most people spend more than $2 per day on more frivolous things than a faster PC.

Understanding How a Computer Works

As so many things are run by computers I believe that everyone should have some basic knowledge about how computers work. But a basic knowledge of computer architecture isn’t required when selecting parts to assemble to make a system, one can know all about selecting a CPU and motherboard to match without understanding what a CPU does (apart from a vague idea that it’s something to do with calculations). Also one can have a good knowledge of how computers work without knowing anything about the part numbers that could be assembled to make a working system.

If someone wants to learn about the various parts on sale then sites such as Tom’s Hardware [1] provide a lot of good information that allows people to learn without the risk of damaging expensive parts. In fact the people who work for Tom’s Hardware frequently test parts to destruction for the education and entertainment of readers.

But anyone who wants to understand computers would be better off spending their time using any old PC to read Wikipedia pages on the topic instead of spending their time and money assembling one PC. To learn about the basics of computer operation the Wikipedia page for “CPU” is a good place to start. Then the Wikipedia page for “hard drive” is a good start for learning about storage and the Wikipedia page for Graphics Processing Unit to learn about graphics processing. Anyone who reads those three pages as well as a selection of pages that they link to will learn a lot more than they could ever learn by assembling a PC. Of course there’s lots of other things to learn about computers but Wikipedia has pages for every topic you can imagine.

I think that the argument that people should assemble PCs to understand how they work was not well supported in 1990 and ceased to be accurate once Wikipedia became popular and well populated.

Getting a Quality System

There are a lot of arguments about quality and reliability, most without any supporting data. I believe that a system designed and manufactured by a company such as HP, Lenovo, NEC, Dell, etc is likely to be more reliable than a collection of parts uniquely assembled by a home user – but I admit to a lack of data to support this belief.

One thing that is clear however is the fact that ECC RAM can make a significant difference to system reliability as many types of error (including power problems) show up as corrupted memory. The cheapest Dell PowerEdge server (which has ECC RAM) is advertised at $699 so it’s not a feature that’s out of reach of regular users.

I think that anyone who makes claims about PC reliability and fails to mention the benefits of ECC RAM (as used in Dell PowerEdge tower systems, Dell Precision workstations, and HP XW workstations among others) hasn’t properly considered their advice.

Also when discussing overall reliability the use of RAID storage and a good backup scheme should be considered. Good backups can do more to save your data than anything else.

Conclusion

I think it’s best to use a system with ECC RAM as a file server. Make good backups. Use ZFS (in future BTRFS) for file storage so that data doesn’t get corrupted on disk. Use reasonably cheap systems as workstations and replace them when they become too old.

• [1] http://www.tomshardware.com/

Syndicated 2013-05-21 04:57:03 from etbe - Russell Coker

Voltage Inside a Car

I previously wrote a post with some calculations about the power supplied to laptops from a car battery [1]. A comment on the post suggested that I might have made a mistake in testing the Voltage because leaving the door open (and thus the internal lights on) will cause a Voltage drop.

So I’ve done some more tests:

Test	Voltage
battery terminals	12.69
front power socket with doors closed	12.64
front power socket with doors open OR ignition switch on	12.37
cigarette lighter socket with ignition switch on	12.32
front power socket with doors closed and headlights on	11.96
front power socket with engine running	14.38
front power socket with engine running and headlights on	14.29

In my previous tests I recorded 12.85V inside my car (from the front power socket which although having the same connector as a cigarette lighter isn’t designed for lighting cigarettes) and 13.02V from the battery terminals – a 0.17V difference. In my tests today I was unable to reproduce that but I think that my biggest mistake was to take the reading too quickly. Today I noticed that it took up to a minute for the Voltage to stabilise after opening a door (the Voltage dips after any current draw and takes time to recover) so a quick reading isn’t going to be accurate.

My car is a Kia Carnival which has two sockets in the front for power and for actually lighting cigarettes. The one for lighting cigarettes has a slightly lower Voltage and only works when the ignition is turned on. The car also has a power socket in the boot (the trunk for US readers) which delivers the same Voltage as the power socket in the front.

Also one thing to note is that today is a reasonably cold day (16.5C outside right now) and my car hasn’t been driven since last night so the battery would be quite cold (maybe 12C or less). My previous measurements were taken in summer so the battery would have been a lot warmer and therefore working more effectively.

Conclusion

The Voltage drop from turning on the internal lights surprised me, I had expected that a car battery which is designed to supply high current wouldn’t be affected by such things. Certainly not to give a 2% Voltage drop! The Voltage difference from reading inside the car and at the battery terminals might be partly due to the apparent lead coating on the terminals, I pushed the probes of my multimeter beneath the surface of the metal and got a really good connection.

The 14% Voltage increase when the engine was running was also a surprise. It seems to me that if you are running a power hungry device (such as a laptop) it would be a good idea to disconnect it when the engine is turned off. A 14% higher voltage will give a 14% lower current if the PSU is efficient and therefore less problems with heat in the wiring and less risk of blowing a fuse.

Also it’s a good idea to be more methodical about performing tests than I was before my last post. There are lots of other tests I could run (such as testing after the engine has been running for a while) but at the moment I don’t have enough interest in this topic to do more tests. Please leave a comment if there’s something interesting that you think I missed.

• [1] http://etbe.coker.com.au/2013/01/24/power-supplies-wires/

Syndicated 2013-05-17 02:57:47 from etbe - Russell Coker

Effective Conference Calls

I’ve been part of many conference calls for work and found them seriously lacking. Firstly there’s a lack of control over the call, so when someone does something stupid like putting an unmuted phone handset near a noise source there’s no way to discover who did it and disconnect them.

Another problem is that of noise on the line when some people don’t mute their phones, which is related to the lack of control as it’s impossible to determine who isn’t muting their phone.

Possibly the biggest problem is how to determine who gets to speak next. When group discussions take place in person non-verbal methods are used to determine who gets to speak next. With a regular phone call (two people) something like the CSMACD algorithm for network packets works well. But when there are 8+ people involved it becomes time consuming to resolve issues of who speaks next even when there are no debates. This is more difficult for multinational calls which can have a signal round trip time of 700ms or more.

I think that we need a VOIP based conference call system for smart phones to manage this. I think that an ideal system would be based on the push to talk concept with software control that only allows one phone to transmit at a time. If someone else is speaking and you want to say something then you would push a button to indicate your desire but your microphone wouldn’t go live while the other person was speaking. The person speaking would be notified of your request and one of the following things would happen:

• You are added to the queue of people wishing to speak. When the other person finished speaking the next person in the queue gets a turn.
• You are added to the queue and the moderator of the call chooses who gets to speak next. This isn’t what I’d prefer but would probably be desired by managers for corporate calls.
• You get to interrupt the person who’s speaking. This may not be ideal but is similar to what currently happens.

Did I miss any obvious ways for the system to react to a talk request?

Is there any free software to do something like this? A quick search of the Google Play store didn’t find anything that seems to match.

Syndicated 2013-05-17 01:53:47 from etbe - Russell Coker

Geographic Sorting – Lessons to Learn from Ingress

I’ve recently been spending a bit of my spare time playing Ingress (see the Wikipedia page if you haven’t heard of it). A quick summary is that Ingress is an Android phone game that involves geo-location of “portals” that you aim to control and most operations on a portal can only be performed when you are within 40 meters – so you do a lot of travelling to get to portals at various locations. One reasonably common operation that can be performed remotely is recharging a portal by using it’s key, after playing for a while you end up with a collection of keys which can be difficult to manage.

Until recently the set of portal keys was ordered alphabetically. This isn’t particularly useful given the fact that portal names are made up by random people who photograph things that they consider to be landmarks. If people tried to use a consistent geographic naming system (which was short enough to fit in large print on a phone display) then it would be really difficult to make it usable. But as joke names are accepted there’s just no benefit in having a sort by name.

A recent update to the Ingress client (the program which runs on the Android phone and is used for all game operations) changed the sort order to be by distance. This makes it really easy to see the portals which are near you (which is really useful) but also means that the order changes whenever you move – which isn’t such a good idea for use on a mobile phone. It’s quite common for Ingress players to recharge portals while on public transport. But with the new Ingress client the list order will change as you move so anyone who does recharging on a train will find the order of the list changing during the process and it’s really difficult to find items in a list which is in a different order each time you look at it.

This problem of ordering by location has a much greater scope than Ingress. One example is collections of GPS tagged photographs, it wouldn’t make any sense to mix the pictures of two different sets of holiday pictures because they were both taken in countries that are the same distance from my current location (as the current Ingress algorithm would do).

It seems to me that the best way of sorting geo-tagged items (Ingress portals, photos, etc) is to base it on the distance from a fixed point which the user can select. It could default to the user’s current location but in that case the order of the list should remain unchanged at least until the user returns to the main menu and I think it would be ideal for the order to remain unchanged until the user requests it.

I think that most Ingress players would agree with me that fixing annoying mis-features of the Ingress client such as this one would be better for the game than adding new features. While most computer games have some degree of make-work (in almost every case a computer could do things better than a person) I don’t think that finding things in a changing list should be part of the make-work.

Also it would be nice if Google released some code for doing this properly to reduce the incidence of other developers implementing the same mistakes as the Ingress developers in this regard.

Syndicated 2013-05-11 13:38:04 from etbe - Russell Coker

Links March 2013

Russ Allbery wrote an informative post about how to determine which charities are worth donating to [1]. He has a link to another article about the charities to which he donates and concentrates on ways of analysing the effectiveness of charities. So someone who has different ideas about which types of charity are worthy of donation could still learn a lot from his post.

Adam Green wrote an interesting article for The New Yorker about Apollo Robbins who is one of the world’s best pick-pockets [2]. Apollo picks pockets as a magician to entertain people and always returns what he steals. Now he is working with neuroscientists who are devising experiments to determine why his tricks work.

Rick Falkvinge wrote an insightful article describing the way that the copyright monopoly is in direct opposition to the freedom to make contracts [3]. It’s a good rebuttal of a common argument in favor of copyright law.

Seth Godin gave an interesting TED talk about the problems with the education system, how and why it teaches conformity and little else [4]. One of his suggestions for improvement is to have students spend their evenings watching lectures by experts and class time asking questions. He also says that everything should be open book and that there is no value in memorising anything – it’s a bit of an overstatement but it’s essentially correct.

Cory Doctorow wrote an interesting article for The Guardian about positive externalities and copyright law [5]. I think that he didn’t choose the best way of framing this issue, but he makes some very interesting points anyway.

Andrew Norton wrote an interesting article about how to reduce corruption in the police force and other government agencies [6]. A large part of this is based on making them subject to the same laws as everyone else, which seems to be a radical idea.

Valerie Aurora wrote an insightful blog post about suicide [7].

Emily Oster gave an interesting TED talk about the factors that determine the spread of AIDS in Africa [8]. It’s quite different to what you probably expect.

• [1] http://www.eyrie.org/~eagle/journal/2012-12/006.html
• [2] http://www.newyorker.com/reporting/2013/01/07/130107fa_fact_green
• [3] http://tinyurl.com/apovrka
• [4] http://www.youtube.com/watch?v=sXpbONjV1Jc
• [5] http://tinyurl.com/a7rutft
• [6] http://tinyurl.com/a227fvg
• [7] http://tinyurl.com/a5zo6tn
• [8] http://tinyurl.com/3f7283s

Syndicated 2013-03-31 13:55:16 from etbe - Russell Coker

Kogan Mobile

Kogan Mobile is the newest virtual telco in Australia [1]. They resell Telstra 3G (not NextG or LTE) and while their coverage isn’t as good as the full Telstra service it’s more than adequate for my needs as they provide 3G coverage to 97% of the population and 2G+3G coverage to 98.5%. Their coverage is probably a lot better than Three who had the worst record of network coverage in Australia yet managed to always provide coverage where I wanted it – I was a happy Three customer for more than 6 years.

Kogan’s main selling point is that they offer unlimited calls to Australian mobile phones and land-lines and unlimited SMS for a pre-paid fee of only $300 per annum ($25 per month on average). My parents have been getting unpleasantly large phone bills which have considerably more than $25 of calls to mobile phones every month so an obvious solution for them is to sign up for a Kogan mobile phone and use it for all such calls. There are other ways my parents could save money on calls (such as VOIP) but a mobile phone is easiest and offers other benefits such as running Android apps (when compared to using a non-smart phone).

6G of Data!

Kogan also offers 6G of data per month, the down-side to this is that they bill in 1MB increments per “session”. I was worried that this might be per TCP connection or something else silly but I decided to sign my parents up for it as they aren’t going to use a lot of data (they claim that they don’t want to use the Internet on their phone but I know better). I’ve done some tests on the SIM I got for my parents. For testing purposes I installed the Kogan SIM in my wife’s new Nexus 4 and had it provide Wifi net access to my phone while we were playing Ingress.

So far after 2 days which involved a reasonable amount of Ingress (I reached level 7) as well as all the usual stuff that happens in the background for two phones (checking email, news, weather, etc) Kogan considers that 177MB have been used out of the 6144MB for the month, which means that even with what is an unusual amount of traffic for us the account in question still isn’t going to use half the quota for the month. Now that 10 days have elapsed with less intense usage Kogan considers that a total of 1373MB have been used.

days	received	sent	Kogan
2	127.24	41.54	177
10	959.39	299.6	1373

Kogan also don’t seem to mention whether they bill for transmitted data. I used the 3G Watchdog app to measure the amount data transferred, the above table has the amounts of data that 3G Watchdog considers were sent and received along with the amount that is listed by the Kogan Android app. My past experience with 3G Watchdog and Virgin Mobile is that it’s usually quite accurate but has been over-reporting the data transfers recently (I think that Virgin is only billing me for downloads while 3G Watchdog counts uploads). So the relatively small difference between the 3G Watchdog report and what Kogan thinks I’ve done means that either rounding the “session” up to the nearest meg doesn’t make any significant difference (which would imply that a “session” can be a long time) or that Kogan isn’t counting uploaded data and the session rounding up only adds about 40% to the total recorded transfer.

My current plan with Virgin Mobile gives me 1.5G per month of quota, so as long as Kogan’s rounding doesn’t increase the recorded data transfer by a factor of 4 I will still be able to transfer more data with Kogan while paying less. One disadvantage of using Kogan is that I might have to tweak programs like my email program to poll less frequently to avoid excessive session charges (a program polling every 5 minutes would use up the 6G quota in 21 days if each poll counted as a session) – although current tests indicate that this won’t be necessary. But the up-side is that there are no extra fees with Kogan, they merely restrict data access – for my use and that of most people I know it’s better to have data access cut off than to receive a large bill.

The Kogan Android App

Kogan has an Android app that will give the status of your account and allow you to change the plan etc. This is quite nice but one major disadvantage is that it’s also a sales app for the Kogan online store. This is bad for the user as some aspects of what I consider the core functionality are limited (for example there’s no way to force a poll of the data usage count or determine how current the data is). But there’s an obvious advantage to Kogan in providing a way to sell their goods that is going to be used by every customer of Kogan Mobile.

The sales part of the app isn’t very functional IMHO, it doesn’t seem to have basic functionality such as sorting a list of items by price.

Benefits of Kogan

6G of data is a lot!

$300 per annum is quite cheap, anyone who makes any serious use of phones will be paying more than that in Australia.

Lack of extra fees means that there is little need to restrict net access. I can risk getting cut off near the end of the month but I can’t risk the potential for hundreds of dollars in excess fees.

The Kogan app shows me the data used so I will probably uninstall 3G Watchdog, having one less program running is a good thing.

You get a free SIM (value $5) when you buy a phone from Kogan.

Disadvantages of Kogan

They are new to the Telco business and admit that their customer service is lacking due to unexpected demand.

If you order a SIM now they state that it will arrive in April. Apparently they are deliberately delaying orders because they can’t cope with demand.

The included call quota doesn’t include international calls. While unlimited free calls in Australia is great if you make many international calls then this could end up costing you more. Other mobile telcos such as Lebara offer good deals for International calls, it could be an option to use a Lebara SIM with an old non-smart phone while using Kogan for your smart phone.

I am concerned about the lack of detail about how data is accounted. If the definition of a “session” changes then 6G could turn out not to be enough. As Kogan is reselling a Telstra service it is possible that Telstra could change the deal without Kogan being able to stop them.

Conclusion

I will move my phone and my wife’s phone to Kogan ASAP. My general idea is to sign us up for Kogan about 2 weeks apart, so if one phone runs out of the 6G data quota then the other phone can be used as a Wifi access point for 2 weeks. If the phones don’t both have their quota end at the same time then there is less chance of both phones running out during a high traffic month.

• [1] https://www.koganmobile.com.au/

Syndicated 2013-03-05 01:24:58 from etbe - Russell Coker

Serious Begging

This evening I was driving through one of the inner suburbs of Melbourne when a man flagged me down. He said that his mother was dying and he needed a taxi ride to some hospital far away and needed to borrow $200. He was saying something about his phone, I wasn’t sure if he was planning to give me his phone number so I could call him to ask for repayment or offering his phone as collateral on the loan (incidentally a well known scam is to offer a stolen phone as collateral for a loan, it’s a way of selling a locked phone that doesn’t have cables).

I’ve encountered many beggars over the years, but he was by far the most serious about it – he demonstrated the level of desperation that I’ve only previously seen documented in history books and reports from travelers who visited developing countries. I will never know if his mother was dying, there are lots of other reasons why someone might urgently need cash (most of which won’t get much sympathy).

I gave him $20 as a gift. If his story was legitimate then I gave him 10% of what he needed so he only had to find another 9 people willing to do the same. If he was lying then I can afford to lose $20. In any case I definitely wasn’t going to do what he asked and withdraw hundreds of dollars from an ATM for him. Also regardless of whether he was telling the truth I didn’t want to have him repay me, if he’s telling the truth then I’m happy to give money to him and if he’s not then I’m better off avoiding him in future. If I had $50 I would probably have given it to him, but $200 is too much.

As I drove off I looked in my rear-vision mirror and saw him running between cars on the road trying to flag someone else down. Running through moving traffic on a Saturday night is another indication of how serious he was, generally someone who’s in a good state of mind and wants a long and healthy life won’t do that.

Syndicated 2013-02-23 13:21:13 from etbe - Russell Coker