07 2003





Another redesign. This time with BlogPower™. Not sure what will happen about content. Probably will get content until I get bored, then wither.

It seems that I haven't been updating my website as often as I should. There's a lot of information that I want to share with people, but I haven't come up with a simple way of getting it all across.

In the mean time, there is a menu to the left there <--

The reason most people have web pages I do not know, however I do like to be able to find out about people by looking at their web pages. I am less interested to find out about their gerbil though. It is like Internet spying, but spying on what they want you to know. So that people can find a little about me I have written these pages.

My PGP/GPG key is available as this file

There is a more blog-style diary here

Recent Changes

RFC 3252

A method of encoding IPV4 packets in XML. This enables cross-platform compatability and lagacy integration support for networking. Let us hope that this will enable IPV4 support for mainframes, via the flexability of XML.

Last updated: 23:11, 23 Jul 2003 Link..

RFC 2795

A discussion of protcols required for the management and care of an infinite typing pool of monkeys. I have not seen any practical implementations, except for possibly Barbara Cartland.


RFC 2322

An amazingly practical solution to a technical problem, dreamed up by a load of computer programmers. I have used this protocol at the LBW 2000 , and it worked really well. However I forgot to release my IP, and it is somewhere in my laptop bag. This leads the protocol to being best for short-term networks, based on private IP blocks.

Last updated: 23:10, 23 Jul 2003 Link..

RFC 1149

This standard reflects a growing need for wireless transmission. Field trials have been completed in Norway .

Last updated: 23:08, 23 Jul 2003 Link..

RFC 3076

This is getting less interesting. In order to cryptographically sign an XML document, it is probably a good idea to do so after parsing it, so that you just sign the meaning. This standard describes how to represent an XML document in the same way as other people.

Last updated: 23:07, 23 Jul 2003 Link..

RFC 2822

This is the standard for the layout of the message content for emails and news articles. Even less softwares appears to give a shit about the content of this one. See also RFC 822.


RFC 2821

eMail, the so-called killer app of the Internet. How does it all work? How does an email manage to get to the right person most of the time? Well if people actually followed the rules in this doccument it would always either get delivered or the sender would get an error message. RFC 821 is also required reading for anyone implementing a mail transfer agent.


RFC 2317

This standard describes a way of delegating reverse lookups for IP address to the people who control them, in smaller blocks than were supported before. I have not seen many providers actually implementing it, partially because users tend not to care what their address resolves to. This standard has one minor disadvantage of liking "/" characters in the domains, meaning that having the filename containing the nameserver config for you domain in a file named after the domain is difficult on Unix systems.

Last updated: 23:05, 23 Jul 2003 Link..

RFC 2068

This is a far more advanced version of the protocol specified in RFC 1945.

Last updated: 23:04, 23 Jul 2003 Link..

RFC 1945

This is version 1.0 of the standard that most of what is popularly known as "The Internet" uses as a transport mechanism. These days most implementations are HTTP/1.1 though.

Last updated: 23:02, 23 Jul 2003 Link..

RFC 1918

Real IPV4 addresses are getting scarse, yet very few people have moved over to IPV6. This is mainly by hiding hundreds of computers on a private network behind a single real IP. These machines can be assigned IPs from the netblocks listed in this standard.


Palm Pilots

I just have to write on the wonders of the humble Palm Pilot, it has sold in the millions and is to be found on the belts and in the pockets of geeks the world over. So, why has it caught on where the Apple newton didn't? And why are people switching from Psions to them?

Well, one thing is the size, it easily fits in a shirt/jacket pocket. This is even more so for the V.

It also had Grafiti, the input system. It does not try to reconise the user's handwriting, rather has a set of symbols with similar shapes to the letters that are easier to recognise. This makes it easy to learn (most people can use the standard alphabet after about 10 minutes) and it makes it largely error free.

Last updated: 22:58, 23 Jul 2003 Link..


I am constantly accused of having far too many computers. It is possible this is true, however computers are Good and Right and Proper as Ian Snell would say (though maybe he wouldn't say it about computers). Computers do Stuff, they sit there and do things on their own and these things help you. They also allow near-instataneous communication around the world, and infalible memory.

Sun Microsystems might like to claim that "The Network is the Computer". That might be a bit of an exageration but networked computers are significantly more useful than computers sitting on their own. The ideal is to never me more than a few feet from a terminal. This way I can check what I have said to people and what they have said to me over email.

I will admit to being a bit of an information junkie. I think it is the side effect of having almost permanent Internet access for the last year and permanent access for half of the previous year. Whenever I wanted to look something up I reached for the computer, and I wrote very little down, and kept few copies of everything as all my files can be reached from pretty much wherever I am. Even better, my Palm Pilot is small enough to fit in my pockets.

For my opinion on the other mobile data-source, see my comments on WAP

Last updated: 18:25, 23 Jul 2003 Link..

What is the point of WAP?

When I needed to renew my mobile phone contract I wanted a phone that would talk via IR to my laptop and pretend to be a real modem. I think that at the time there were two phones around that could do this. The Motorola Timeport and the Nokia 7110. In the end I got the Nokia, as it has a nicer screen, is cheaper, and I don't think that tri-band is really at all important to me.

This new phone of mine has WAP capability. Now this has been advertised mainly by BT Cellnet as "The internet on a phone". Well it really isn't. Wap is shit. It is not really an Internet connection. You can only use it to access WAP sites, specially written in WML. When accessing these it is really slow, and keeps on losing connections. This is not including the fact that it is really quite expensive.

However, I have found at least one positive use for WAP, and the WAP sites out there. This is the WAP interface to RailTrack's timetable system, and allows me to check the timetable for connections when I am on a train without calling up the rail enquiry line. That said, it is probably cheaper to phone the people at the moment, but it wasn't in November when Breathe.com were wasting their venture capital on giving free WAP calls. Maybe the future will bring cheaper calls and lots more useful WAP sites. Alan Cox has already written a WAP->IRC gateway (see his diary entry for December 9th 2000), though I don't think that is really that useful and I haven't seen it released. There is also a WAP plugin for irssi the IRC client, though I haven't used it.

The Future

So, what will WAP do in the future? I really don't know the answer to this. I suspect that when phones have higher spec processors and higher bandwidth links, WAP will be replaced by a real internet connection. However until that time will it be useful? Well, the main thing I see in it is that it is encouraging large companies to put together low-bandwidth sites, with thought into navigation and maybe this will rub off on the designers of webpages.

WML, so what is it?

WML is an XML schema for describing pages so that they can be displayed on a WAP phone. The WML code is parsed by the WAP gateway and converted to a bytecode before being sent to the phone. This is to save on size for the download and the memory on the phone, and also so that the phone client doesn't need to do the XML validation.

A WML page is a "deck" of "cards", with each card a screenfull of information and the ability to move between cards. The idea is that your phone downloads a deck, then you can browse that deck without needing a connection. However in practise, you are still connected whilst you are browsing the deck, so you gain little there.

The people who wrote the WML spec appear not to know too much about security models and will, in a lot of cases, trust the client. For example, there is a case where a given card in a deck can be locaked until a password is entered. This is relying on the client application (in many cases a phone, but not exclusively so) to check the password and keep the data hidden untill it is entered. This is not secure, as I could write myself a WAP browser that didn't bother asking for the password, or if I really couldn't be bothered to do that, I could take a memory dump of someone else's WAP browser application and take the page out of that.



This module sprang out of the need for a "library" for the Computer Society. However it has no where to store one, and little interest and finances for new books. The idea was then had, that we could collect pledges from people to lend their own books to the Library.

As expected from a project of the computer society, it is a little over-engineered at the moment, as it is based on data-structures created for the OUSFG (Oxford University Speculative Fiction Group) library, that is a lot more complicated than this.

The PerlPOD doc is here .

There is a tar of the distribution of the module here, and the files are available individually, here .

Last updated: 15:07, 23 Jul 2003 Link..


I have some photos from the first two summer courses at the Croft. These will be here soon. If anyone else has any photos, particularly group photos from the end of courses, would they be able to scan them and send them to me, or if you cant scan them, email me and we might be able to work something out.

This may not be the case, it looks like it may end up as a password protected list of thumbnails and some automated way of getting hold of them. Anyway, sharing of photos is to be encouraged, this is why god invented digital data.

And here is the link to the private area containing the photos Bethan took of our visit in summer 2001 (I think).

Last updated: 14:44, 23 Jul 2003 Link..

Mailing lists

I run a group of mailing lists for people who have been on the courses, there is no compulsion to join, but it is good to keep in touch.

gift - For general announcements. The idea is that this is a low traffic list for people to keep in touch via. Appears to be really low traffic at the moment.

gift-j - The junk list, for the more prolific emailers amongst us to create in-jokes and talk for ages. This leads to fun and better keeping in touch.

ox-gift - A slightly more specific list, designed for people in Oxford to plan meeting each other, and group trips to other meets, but there appear to be some non-Oxford people on it. This is a very quiet list

To subscribe to any of these lists, click on the name of the list. Then fill in the form. If this really is above you, then you can email me dave (at) earth.li and plead with me to put you on a list.

Last updated: 14:43, 23 Jul 2003 Link..

C++ and compatability

Tue Jan 14 2003

This morning (and most of yesterday), I have been fighting with C++. Trying to compile and link a program against xerces.

Due to my not following instructions correctly, and being given duff information, I was unable to compile it. This is fine I think, I will go and download the binary packages, these will have been compiled correctly.

I download the binary package, untar, and try to link against it. Loads and loads of errors. It turns out that GCC being shifted up a major version breaks binary compatability, so I cannot link against the library compiled with a different version. Hmm.

Next stop, the nightly builds of the development branch, there is going to be a release in a couple of weeks so it should be reasonably stable. Download this (it has been compiled with the same version of gcc), and untar. Now I get obsure syntax errrors when trying to compile my code. It turns out that now Xerces has been placed into a C++ namespace, and I need to prefix every reference to a xerces classname with "XERCES_CPP_NAMESPACE_QUALIFIER". For example:

   XERCES_CPP_NAMESPACE_QUALIFIER XMLString::copyString(fileName,systemID);

As you can see, this does wonders for code readability. I had to add these in about 50 places, and my code is only minimal. I would not have liked to convert a larger piece of code without automated tools.

This allows it to compile, which is a good start so I go and install the libraries and binaries on the server (running a slightly older version of the Operating System) and try it. It turns out that the machine with the new version of the compiler, also compiles against a more recent version of the standard C++ library, meaning that it doesn't run. At this point I could install the newer library, but that would end up with this machine having an aditional 20Mb library for compatability reasons and it isn't exactly ideal.

In the end, I just got better advice, and so was able to compile the new version on the server on which it was to be run. This was what I intended in the first place. Finally, you may have noticed that we had to change our code in order to use this new version. This code does not compile with previous versions of Xerces that do not define the namespace, leaving us with a problem, code that only works with the latest version. Luckily the preprocessor comes to my aid here, adding -DXERCES_CPP_NAMESPACE_QUALIFIER= to the compiler options effectively removes this.


This should not have been anywhere near as difficult as it was. Namespaces are possibly a good idea, but the should probably be implemented less like they were an afterthought. Also the binary format for libraries would be a lot nicer if it were a standard, as this would allow more sharing of libraries between software compiled with different compilers.

Last updated: 11:22, 23 Jul 2003 Link..

Otter Splicing

This was written by a collegue, Robin, however it appears to have disappeared from his website, so I include a copy here.

Otter Splicing (Oh-tur suh-per-lice-ing)

1. Lost art of genus Lutra (and related genera) amalgamation, by means of persuasion and force. Very often using bulbackah rummy sticks for 'back-draft'. Outlawed in many backward states; Still practised in Oxford (UK) and other parts of Englandshire. Most commonly at a time of special celebration (e.g. birthday).

2. Insult used by extremely intelligent (nee. sexy) persons to persuade lesser spotted humans to consume alcohol -- usually in the Harcourt Arms (see entry entitled Best Pub in the World). Websters' Sport and Hobbies Dictionary 1987

Many have requested of me, as to what, rather than who, is Otter Splicing. I therefore, intend to layout, rather in the manner of Hannibal (from the A-Team), a short, succinct explanation of this most fascinating of sports.


Preparing for Otter Splicing (OS) is very simple and potential players rarely find themselves short of equipment. Indeed, missionaries who found themselves in Africa even though they were sure the bus had said Fleet Street on the front were able to teach locals the elements of the game using the most basic props lying to hand.

Long time enthusiasts will no doubt baulk to see the diaries of Mary Sheldon, a six foot giant of a man who took it upon himself to convince the chief of a local tribe of the joy of Christ through playing and exercising command of OS. His zeal was rewarded with one of the most remarkable games of his career. Yet, to start with he only used his trusty tungsten carbonate drill. As the following extract from his memoirs shows:

"The Mata-Butu chief seemed bemused at first, but with the first otter down he soon began to circle the cage-mangler like a seasoned pro stepping out to bat a Lords. Two or three splicings through he suddenly looked into the sky and bellowed 'Bloody Otters!'. At that moment I knew we had him. Quite an achievement considering that all he was using was an oil rig."

To come back to the point: Players must ensure that all friendlies have been equipped with bolsters and all enemies with grouting morselets. It is thoroughly improper to have everyone with morselets as this produces imbalance in each teams' otter-circling.

If players must insist on unilateral morseleting then, really, Pelican Faucet is the game rather than Otter Splicing.

Beginning Play

Now you can see how ready anyone is to begin Otter Splicing the question on your lips must be: "How do we start?".

This is a simple question to answer: To begin a game, simply line up the selected Otters and offer the opposing team the 'sweep'. This is known as 'offal jotting'. The opposing team can either accept the 'sweep' or pass it back.

To the beginner this can seem pointless as the first team to get the 'sweep' seemingly has the immediate advantage. But this can be deceptive. Professional teams have been know to pass 'sweeps' back and forth for considerable amounts of time - sometimes hours. Indeed, one match in India 1872 was said to have consisted entirely of the passing of 'sweeps' until one team conceded out of sheer exhaustion.

It is all about knowing your otters; and that is a subject we will have to cover at a later date. In the meantime, begin the game with 'offal jotting' and then the 'sweeping' team may begin.

Last updated: 10:54, 23 Jul 2003 Link..


More and more laws are being passed now in order for lawmakers to feel they have control over the Internet. These laws are largly reactionarry and are written by non-technial people. This means that they have provisions that do not cover the original intended criminals (or maybe they originally intended more than they claimed).

There is also increasing pressure from the US to expand their laws into other countries. Their companies openly flout the laws of countries such as France and Singapore, in the name of free speach. Yet sites that contain unsavoury content, or more often crytographic code, for example the DeCSS code, get threatened by letters from American lawyers, under US law. This strongarming the world into having the same laws is hypocritical on the behalf of the US, as they will not sign treaties recognising the International Court until they include exceptions from procesution for crimes such as Genocide for American citizens. Why do they need protection from such acts? Do they have a guilty conscience about something? or just something they are planning. I will stop here, as American foreign policy is covered elsewhere.

Basically, our lawmaking bodies are insufficiently technical, and so get advice from lobby groups and other interested parties, leading to legislation that makes almost everyone a criminal, and leaves loopholes which are then patched by expanding the scope of the original rules to cover more and more cases.

Ok, so other people are more coherent at making this point, so I will link to a few here.

Last updated: 10:46, 23 Jul 2003 Link..

TV Licencing

I am writing this page, mainly so that I don't lose the following very good links about TV Licencing in the UK. Please read them before reading my comments, as otherwise I suspect I will make little sense.

Having read these, one thing that springs to mind is the fact that the TV licencing people fail to realise that these people who do not have a television, tend to be people who have lots of spare time to write interesting letters about anything that annoys them. It almost makes me want to get rid of my TV/stop watching television (as I wouldn't give up my DVD collection), just so that I can join in the fun. The most I have ever done was write in green crayon "I HAVE NO T.V." on one of their letters, when I was a student.

It is my opinion that the Licencing people intentionally mislead people and use threatening language in order to maximise revenues. It may well be true that the majority of households in the country have a television and use it, however that is no excuse for assuming that everyone has one. That is the guilty until proven innocent basis that should not exist in this county. However we are seeing more and more examples of guilty till proven inocent in this country, such as the rules about encryption keys under the RIP bill.

And finally, the situation on getting a refund. I cannot find clearly the conditions required in order to obtain a refund on a licence for part of a year. The only thing that I have actually discovered is that students not needing a licence for July, August and September can get a refund for this period. I can see nothing to cover such events as two licenced people moving to the same address or someone selling/throwing away their televisions. Or for that matter, detuning it and no longer watching it.

Last updated: 10:43, 23 Jul 2003 Link..

The Sheldon Guide to Charm and Tact

Some of the fools at work suggested I write this guide. They say that I get on really well in an office environment, both when dealing with co-workers, and with customers.

I am sure the same techniques would work with the ladies, however I don't have a girlfriend, so I cannot confirm this.


At all points, make subtle references to how good you are, better than them. People always respect their betters, and will respect you for it. The worse they feel, the more of a crutch your excellence can be to them. Do not let this one slip.


Far from being the tool of the weak-minded, sarcasm is a powerful tool. Particularly in email where its use cannot be proven.

If you think that the answer to a technical question should be obvious then respond with a technical answer that is almost exactly the opposite, or that is simply technobabble. Done in a sufficiently sarcastic voice, this will both impress and belittle your co-workers.

The best feature about sarcasm is that Americans just don't get it. Not a single one of them has the intelligence to understand that you might not mean exactly what you said. They are all far too busy trying to blow themselves and the rest of the world to pieces, mainly fuelled by their narrow-minded bigotry.


When asked a question, answer as succinctly as possible. "yes" or "no" are ideal, particularly as the answer to an either-or question. This will wrong-foot the asker, and save you the time expanding on the answer.

Never just answer the question. Giving a hint as to where the answer may be found. This emphasises how much more you know, whilst not pointing out that you don't actually know the answer to that specific question. While they are distracted looking it up, you can look it up quicker, once again emphasising your superiority. People respect a helpfully superior person.

Always point out spelling mistakes and typos in the work of others. Maybe try using it as an excuse to mis-parse the question before answering it. You never know, they might learn to type better/use the language they have been speaking for most of their life.

Make it seem like even the most trivial of work is actually an effort. This means that when you do this for someone then they appreciate it so much because of the amount of work it is.


If someone does well, comment on it. Try to sound surprised though, you don't want them think that you expect them to be getting better. That will just set them difficult to reach goals and depress them. We don't want that.

You also don't want to seem too interested in other people. They might think you are after their job or something. Seem detached, even depressed, when they tell you the interesting stories about what they are doing.

Following Instructions

Always follow instructions to the letter. Particularly instructions you feel are incorrect, given by customers. Wait for it all to blow up in their face, then sit in the corner going "ner ner ner I told you so". This can be effectively accomplished virtually, rather than by physically sitting in the corner, thus saving you looking silly.


It is important for people to know their failings, preferably in as public a forum as possible. Make a joke about it or something. They don't want someone pointing it out subtly later on, they will become paranoid and will think it is a bigger issue. Much better to make light of it.

Express shock at any changes that occur, no matter how small, or how positive they are. This shows you have noticed. People like to be noticed.

Last updated: 10:11, 23 Jul 2003 Link..


This is a page that will include a map of where my house is. It is not in a linked part of the site.

Last updated: 00:30, 23 Jul 2003 Link..