For the 3 weeks I was in the UK recently I used a UMTS modem (i.e. like a 3G phone) to surf the web and do all my work. Going round to my friend Robin’s house, who also works in IT, he does all his surfing through a cable from his phone to his computer: i.e. also UMTS.

At least in the UK, this is extremely popular. Also in Asia it makes a lot of sense; they have excellent high-speed mobile phone networks there and all ones preconceptions about the Asians having the latest handset devices: I can confirm first-hand that they’re all true.

As we all know and have been experiencing since about 2000, more and more phones are going to get more powerful and have larger screens. Full browsers will (and do) run on them. They will also be UMTS devices.

And for those people who don’t surf via UMTS, nearly everyone I know surfs at home using WLAN. A lot of offices use WLAN too. And obviously all the surfing at airports, coffee houses, hotels, conferences etc. all goes on via WLAN.

UMTS and WLAN have high bandwidth, but they have extremely high latency compared with a cable connection. That means that although the bytes flow fast once they’ve started, it takes a long time for the first byte to arrive.

I am quite proud of the fact that when I designed the “Uboot Joe” software (Windows software which ran on the user’s PC, sat on the notification area by the clock, and communicated with Uboot) I took this into account. Every action you do with the Joe is at most one client-server round trip. For example to view all the thumbnails in a folder, there is a single request from Joe to the server like “get all data in folder_id” and the return structure is a) information about the folder, b) information on all the photos within the folder, and c) all the binary JPEG data for the thumbnails of all those images. You can try using the Uboot Joe on a UMTS link, and it works faster than any website.

Contrast this design with HTML. The first response from the server contains <img src=xx> tags and only once that has been received can the browser make the further requests necessary to retrieve the images. If the first bytes of every response take a long time to arrive, then the user experiences that “long time” twice before they see the data they requested; first to get the HTML page then second to get the images.

In fact it’s worse. If a page has 50 embedded images, it doesn’t open up 50 concurrent connections to the server (for good reason). Instead it opens e.g. 4 connections. Which means that e.g. image number 5 has to wait for the “long time” of fetching image 1 to complete. (Some sites try to get around this by having lots of servers with different names e.g. img341.domain.com and distributing the images over these servers.)

And it’s even worse than that. Even if the application only does one round-trip to the server, the underlying protocols might do more round-trips, for example firstly to contact the DNS server to get the IP address for the domain name used in the URL; and then secondly to request the data from the server.

In addition to this being a problem with UMTS and WLAN, one also has to take into account that the Internet is global. When I’m in Macau accessing European servers I get a round trip of about 300ms. So if one adds three “long times” to an otherwise extremely fast request—easily done—one has added a whole second on to the time the user has to wait. And Jakob Nielsen says that after 1 second in total, users start to lose focus on what they’re doing.

So to design applications in this age, one needs to be aware of the number of serial server round-trips (i.e. the number of times you need to ask the server for something, and only once it’s been delivered, must you ask the server for something else).

For example:

1. An HTML page which contains an external CSS file, and this CSS file contains URLs to images.
2. Pages with many images. The browser only requests a few files from the same server at once, so again the response to image number 1 must be finished before the request for image number 3 can begin.
3. Javascript software which does multiple serial calls to the server, e.g. “get session token for username/password” then “get info to display on page for session token”.
4. A form which submits data to a piece of software. The software does something but instead of returning a result page, returns a redirection command to a “real” result page. Often done to allow one to hit “refresh” safely on the result page, or make the URL of the result page look nicer.

GWT is excellent in this regard. It has the ability to download lots of those small icon-size images in one request (it makes one big image on the server and chops them up again on the client) and it makes you explicitly aware of the number of server round trips by forcing you to define interfaces for client-server interactions - as opposed to some automated scheme where you write code and the framework decides when to insert client-server round-trips. (Wicket makes client-server round trips easy with AjaxLink; my fear is it might be too easy, and one might do them too often, and lose the overview of how many are happening).

Pre-caching is a good idea too. E.g. if you are a photo viewer application, with a photo shown full screen with a “next” button, it makes sense to load the image on the “next” page even before the user’s clicked on it. That download won’t interfere with the rest of the activity the user is doing, as the bandwidth is not the bottleneck, just the time between starting the download and the bytes starting to arrive at the client. (Although one can’t download too much without the user noticing, as some people pay per MB!)

But the most important point, I think, is: these days, one must test ones web applications on a high latency connection. Generally speaking, historically I have tended to develop locally (everything installed on my laptop), or I develop in an office with a network cable and high-speed Internet and a link to the data center where the test server sits—and the office is in the same country as the server. Maybe this sounds strange, but I think one should develop web applications while using a UMTS card.

Not even the simplest things work with computers these days.

I have an Excel sheet and I want to copy a value into an MSN conversation. On Windows. Notice the vendor of all these products.

1. I copy the cell and in the middle of the sentence I’m tying into MSN I press Ctrl-V. MSN hangs for about 5 seconds. Then a notification is sent to the other party that I want to transfer a file, something .tmp.gif, i.e. an bitmap image of the value I’m trying to my sentence. Of course the other party hasn’t seen the first part of my sentence yet, as it’s still in the message composer and I haven’t pressed Return yet, so this file transfer request would come as a bit of a surprise to the other party.
2. No problem - I can double-click the cell in Excel to edit it, and copy the characters from the cell, as opposed to copying the cell itself. However, the cell is a formula. That means that when I edit the cell I get text such as =D1+E9 as opposed to the numeric result value which I wanted to paste into the MSN conversation.

So what is the solution? As far as I can see I have to have both windows open side-by-side on the screen, and type in the value into the MSN window that Excel is displaying….

Before I left Vienna, the Internet stopped working in my flat. There were some major electrical engineering works going on in the building, so I assumed this was the cause. Now I’ve come back, they’ve stopped, but my Internet hasn’t started working again.

The modem, from my ISP Chello, was an “ARRIS type”, and the “online” light (light 2 in the following diagram) was permanently flashing.

What was the modem trying to communicate to me? On the Chello homepage it says one should turn the modem off and on if this happens. Needless to say, by the time I read that helpful advice, I’d already done that quite a few times!

But it turns out there is a button on the modem, which is marked “standby”. Amazingly enough pressing this has the effect of

1. making the Internet no longer work, and
2. making the “online” light flash instead of being constant.

Why would one want that? How had it come to be in that state?

Anyway, pressing it resolved the problem, and freed me from the necessity of making a telephone call to Chello support.

I’m heading back to Vienna tomorrow (Saturday). I land at 17:30 or thereabouts.

Alas it’s too late to go to BarCamp Vienna (on Saturday), which upsets me greatly. I think that’s the 4th BarCamp I’ve missed due to not being in Vienna. Hopefully I’ll be here for the next one. I tried to change my flight but the cost would have been over € 300.

In addition there’s an open day on Sunday at the Tudor Barn in England where I’m getting married. It would have been lovely to go to that but that also would have required a change of flight (in the other direction).

And hopefully when I get to Vienna, my toilet will be OK…..

The night before I left Vienna (mid December), which was a Saturday, I went to the pub with some friends. Needless to say my plan was to pack on the day of departure, Sunday. I got back late, but with 6 hours sleep I would have had (just) sufficient time to get up at 9am, pack, and make my train.

I got back and to my horror — the whole of my toilet floor was covered in water (thankfully water into the toilet not out of it!). I had to leave the next day, a Sunday, it was now 03:00 on that Sunday morning, and my parents had paid for the hotel room in the Austrian village where they we were staying, for Sunday night.

What I did first—obviously!—was panic! What I did second was to ring the Austrian girlfriend of the friend I’d been out with that night. I knew she’d be awake as we shared a taxi together and I got out first. She advised me of an Austrian 24-hour plumber I could call. That was a real life-saver!

Then I made a bit of a negotiation mistake. The plumber advised me on the phone he only accepted cash. I pointed out that I would only be able to get out € 400 (the limit on my card). While he was on his way, I went to the cash machine and got out that full amount. Once he’d done the work he told me the bill came to € 398, quite a coincidence…?

Now the thing about my toilet is that it used to be the floor’s toilet. So the main tap which turns off the water to my flat doesn’t actually turn off the water to the toilet; the toilet is before that tap. But not to fear, there’s another tap just for the toilet. I started to turn that tap and the toilet did stop dripping, but now the tap started dripping! I turned the tap back on, hoping to revert to the situation that the toilet was dripping, but now they were both dripping! Nightmare.

When he came, he said he’d have to turn the water off in the basement. Now when I moved in to my flat 9 years ago, there were a bunch of keys hanging up on the inside of one of the cupboards. To this day I don’t know what they’re all for. So I grabbed them all and I set off for the basement with the plumber who’d just arrived; at 04:00 Sunday morning, in winter in continental Europe, chilly with snow on the ground outside, 5 hours before the time to get up (and not fully sober, I must confess, although seeing all that water helped.)

Basically under the building where I live—which is neither modern nor well-maintained I must assert—there is a labyrinth system of brick tunnels. It’s really amazing. And so many wires and pipes, in all different directions. And all so dusty and nasty! And one of them, probably, was the tap to turn off the water to the tap next to my toilet.

We didn’t find the tap. He even asked me if I had any documentation on the tap structure of the building! So he did what I can only describe as a “hack” on the tap next to my toilet to make it stop dripping and also stop supplying water to the toilet. He fixed the toilet with what might also be described as a “hack”. I finally got to bed at 6am.

A few hours later, I awoke, I packed, and I got my train. Needless to say I forgot any of my skiing clothes (I was going to a ski resort, although not to ski), I brought normal clothes including some summer clothes, enough for about 4 days. I wondered why my case was so light yet I was going away for so long? But it didn’t occur to me what the reason could be or what I could do about it!

I have been living with the consequences of that bad packing experience—the complete lack of clothes—for the last 6 weeks.

Anyway - this is all to say, I hope his hack worked? I’ll see when I get back to Vienna tomorrow.

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As those who know me know, I was sent a bill for € 2600 from T-Mobile Austria because I’d used their data card in the T-Mobile UK network. I’d downloaded 260MB. T-Mobile Austria claimed that T-Mobile UK was a “foreign network” (choosing to be one brand only when it suits them) and charged me € 10/MB despite charging only € 39/month for 800MB when I’m in Austria. Quite a price difference. It clearly didn’t cost them that much, they only adopt this strategy to rip people off. I even went to the consumer protection agency in Austria who agreed it was outrageous. They wrote T-Mobile AT a letter asking them to reduce the bill. T-Mobile promptly wrote back and said “no”.

I considered switching operators in Austria, but I looked around, and it turns out all the other operators have a similar price structure. Apart from the operator 3. They have a no-roaming-fee policy, as long as one stays within their network.

So, now I have signed up for 3 UK (as I was in the UK at the time I needed it, and I figured with no roaming costs, it doesn’t matter where you sign up). If I’d been with 3 before rather than T-Mobile before, my monthly bill would have been £10 rather than € 2600.

But I was, nevertheless, still extremely suspicious of network operators, after my experience with T-Mobile. And with good reason, it turns out.

3 supply a tool (with a horrible UI! - but it works) to allow you to connect to the Internet. I have only used their tool to connect, not any other. And helpfully it tells you how many MB you have used. You get 1000MB included in the monthly fee and every extra MB costs 10p.

But the other day I booted my computer and found the number of MB used had gone down overnight! The display on the previous day had been around 400MB and now it was showing around 300MB. This couldn’t be right.

One of the things I learned from my T-Mobile experience is that operators have websites where you can check your current bill. Supposing that 3 also had such a facility, I went around looking for it and sure enough it does have one, called my3.

And I suspected, the tool was showing an incorrect amount.

• Here is a screenshot of the tool which says that 439+91MB have been used, i.e. 530MB have been used, so 470MB should be remaining from my monthly 1000MB.
• A screenshot of the website however clearly shows I only 228MB are actually remaining.

If I had believed the 3-branded tool which installs itself onto the computer the first time you plug the 3-branded modem into a USB slot on your computer, I would have surfed e.g. 242MB more than my 1000MB allowance - or maybe more if the used amount goes down again mysteriously. That would have cost £24 extra, which is not the end of the world, but it’s not the £10/month deal I signed up for.

I wrote to customer services explaining the situation and suggesting they file a bug report against their software, as it displays incorrect data, and the data is directly relevant to billing. Amazingly a customer services representative called me and explained to me that only the value on the my3 website was the authoritative value. I explained that I understood that, but he should still get the program fixed, or at least display a warning. He said he’d “look into it” but it didn’t sound to me like he had any power to do anything about that. But maybe I’m wrong.

But basically, be very careful of mobile companies concerning data tariffs.

1. T-Mobile AT charging € 39/month for 800MB is € 0.04 per MB. They charge € 0.20 for any MB used over the 800MB limit. But roaming to the network apparently with the same brand in the UK, they charged me € 10 per MB, which is 50x € 0.20. But they’ve got the UMTS equipment in the UK anyway, for their UK customers who are on similar price-plans. The only extra complexity is provisioning and billing. I don’t believe that costs 50x more than building the UMTS network in the first place.
2. 3 UK produce a 3-branded tool installed from a 3-branded modem which came with my 3 contract, which displays blatantly incorrect data. Upon calling customer services one learns one cannot trust the tool, one can only trust the my3 website. But that is far from obvious. Anyone trusting the number on the tool will end up with a bill for a higher number of MB than they had believed they had used.

I mean I’m really kind of of the opinion that Java Sevlets, at least when using Tomcat and the other open source tools, don’t work. I mean surely it can’t be difficult to implement a Servlet container or logging framework!

I just tried to start Tomcat and it refused to start because of the following error:

log4j:ERROR Error occured while converting date.
java.lang.NullPointerException
  at java.lang.System.arraycopy(Native Method)
  at java.lang.AbstractStringBuilder.getChars
  at java.lang.StringBuffer.getChars
  at org.apache.log4j.helpers.ISO8601DateFormat.format
  at java.text.DateFormat.format
  ...
  at org.apache.log4j.Category.log
  at org.apache.commons.logging.impl.Log4JLogger.error
  ...
  at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt
  at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run
  at java.lang.Thread.run
log4j:ERROR Error occured while converting date.

So I just hit “start” again, and this time it starts without error.

And people trust their mission-critical server architecture to this stuff!

Well I can’t be beaten by Barbara can I :)

• Skiing in Mallnitz Austria (Jan)
• Living in Macau (Feb-Mar, Jun, Oct-Nov)
• Two weekends to Hong Kong (Mar, Jun)
• Holiday in Yangshuo (small Village in China, Apr)
• Vienna and London obviously!
• Stassburg to visit my friend Johanna
• Venice and Salzburg in August
• Malaysia (Sep)
• Seefeld with my parents (twice: Jan, Dec)
• Paris for New Years

I was talking to my father over Christmas and he said that in his career, job titles of bosses had been various things, such as “leader of”, “head of”, etc. But he said when he started, they were called administrators.

I think that’s a great name for a boss. It emphasises that the job of the boss is to get out of the way of the employees and let them get on with their jobs. It also emphasises the positive aspects of a boss from the perspective of the employee, i.e. certain things which do not directly relate to the job, yet have to be done—such as coordinating holidays, managing pay, managing the office—should be done by the boss, to let the employee focus even more solely on their area of competence.

Imagine “administrator of software development” rather than “head of software development”. That sounds to me much more like how it should be!

Recently I was working on a website which was developed in PHP without a web framework. A lot of things were programmed manually which would normally be taken care of by a web framework (for example things like: in case of an error, the HTML fields on the form are re-populated on the response page).

So I came up with an extensive set of test cases, and made sure I used them all on every field on every page.

These are the tests, in no particular order.

1. On a form with radio buttons and text fields next to the radio buttons, clicking on the radio button should position the text cursor in the text field (as typing there is the next thing you’re always going to want to do).
2. Clicking on the text field by a radio button should select the radio button.
3. Checkboxes and radio buttons which have text beside them must have the text in a <label> so that clicking the text selects the checkbox or radio button.
4. On a <form>, pressing return must do the same as clicking “OK”.
5. Pressing the TAB key on the keyboard should progress from one field to the next in a reasonable order.
6. Every action where something is done (e.g. delete an FTP account) should have a confirmation text on the result page like “ftp account XYZ deleted”. I think it’s important to include the name of the object being acted upon in the message.
7. All forms should use “post” and “get” appropriately. I mean various people have various strong views about when to use one and when to use the other. But for me the difference is the browser’s “are you sure you want to repost?” message when you click refresh. Do you want it? If so use “post”, otherwise use “get”. Also bookmarkability.
8. Is there a reasonably small amount of HTML generated? E.g. in uboot to display the address book page requires about 1MB of HTML to be downloaded to the browser (not including any external CSS, graphics etc.) That’s too much.
9. The back button should work everywhere. (E.g. Uboot multimedia gallery: click on a picture, click back, you’re at page 1 of the gallery rather than the page you were on.)
10. Strings to long? Then “…” should be displayed, to avoid breaking the layout.
11. If breadcrumbs are used, (i.e. main page > hosting > ftp accounts > ftp account ‘x’) then they must work. Ideally they should contain data such “ftp account ‘x’”.
12. While loading a page on a slow connection, is the text readable before the background image loads? E.g. white text on a black background image may not be readable before the image loads. There should be an alternative flat-colour background of a similar colour. (Thanks Helge for pointing this out a few years ago!)
13. While loading the page, does the page move around a lot due to width=x height=x attributes missing on an <img> tag? It’s annoying when you start to read the text on the page and then it moves a few seconds later just because some logo has finally loaded.
14. Every time there is an error in the form and the page is reloaded with the error: is the original data still in the form?
15. In all places where the user may enter free text: Do weird non-Latin1 characters work correctly, both entering them and displaying them? Do ” ‘ work correctly? Are < > & displayed correctly? Is all of this written to the database correctly? (Sometimes the browser sends &#123; style code to the server. If this isn’t escaped on the display code then the character may appear to have been processed correctly. But you don’t want &#123; strings in your database data.)
16. Type in long values into text fields. Values should be neither truncated nor should an internal error be produced (default behaviour if you’re using MySQL or Oracle respectively)
17. If there are any id=nn type parameters in the URL, then adding or subtracting 1 from the URL should not allow you to view other people’s content.
18. Is the <title> tag set usefully? This is necessary when you use the down-arrow by the “back” button on the browser, to determine how far back you want to go. A whole lot of options such as “MyWebsite”, “MyWebsite”, “MyWebsite” is not very helpful.
19. Test in a high-latency environment. Such as over a UMTS connection. If there are a lot of redirects, or images referenced from CSS referenced from HTML, or Javascript making AJAX calls, processing the result then making more calls, then the page will be slow, but work fine over a LAN connection.
20. Test in an unreliable environment, e.g. where packets get lost. Google Spreadsheets, when you type in a value, lets you continue editing the page while it’s sending the value to the server. But if there’s an error or timeout with the sending you see an error, and the cell is reverted to its previous value. You simply have to type in the same data all over again. Instead of that it should remember your data, and display an warning “can’t connect to server right now; retrying…”
21. If you type in URLs in capitals or mixed case: do they still work? (Thanks again Helge!)
22. AJAX progress indicators: Is it the case that you’ve written an AJAX site, and when the user clicks an action, absolutely no visual feedback is given to the user that he’s clicked? You need to have some kind of feedback, e.g. the “loading…” of gmail.
23. Are the buttons large enough to be easily clicked on? E.g. confirmation page with “Yes”, “No” options displayed as links in a tiny font. They’re hard to click!
24. Do the colours work even if you view your laptop at a weird angle? A site I was using recently used a white background (what a surprise..) and to highlight the tool you had selected used a light-grey background. Worked fine on their monitors I’m sure, but at the airport with your laptop on your lap, they’re difficult to see.
25. Does the site work, or at least fail gracefully on old browsers? An error message immediately is preferable to allowing the user to type in lots of text then lose it when the user presses “OK”, due to some browser incompatibility issue (e.g. MediaWiki on Safari 3 beta for Windows)
26. What about small screens? My parents computer uses 800×600 and I use my Laptop in 1064×600 normally. In Google Reader I can hardly see any feeds at that size. The whole screen is taken up with toolbars, menus, etc.
27. Is the session timeout compatible with the company’s policy? E.g. do you really need the user to log in again after 10 minutes, i.e. when he just had to nip off for a meeting?
28. If the session expires, what happens to the user’s data? Composing a long email and clicking “send” only to receive the response page “please log in again!”, and losing the email, is wrong.
29. If there is a possibility to log in on every screen (e.g. “logged out” at the top-right of the screen, or like on uboot), then logging in should take you back to the screen where you were. Because that’s what the user would want.
30. If you are logged out and go to a particular screen e.g. via URL or bookmark sent while a user was logged in, do you get useful information? A redirect to the homepage is also OK, but “general error” is not.
31. If you go to a page with a form, is the text cursor already in the first field? Or do you have to reach for the mouse and click on the first field in order to use the form on the page?
32. Does the site look good on both LCD monitors and conventional monitors? Some colour combinations (e.g. dark green on a light green background) are perfectly readable and look nice on LCDs, but are completely unreadable on conventional monitors.
33. If a browser window is open, and a user is logged in, and from another browser (or directly in the database) that user’s password is changed, the user deleted, or disabled, is the first browser immediately logged out?