Author Archives
18
Dec 09
Polite extensions in Chrome
Noticed a nice design in Chrome’s extension mechanism:
Extension requests additional permissions
4
Dec 09
Google Public DNS benchmarking
Yesterday, Google announced a public DNS service that promises to speed up your browsing experience.
We here at x7 Labs like our interwebs speedy, so I decided to take a quick look at the service. For testing, I used my home 110 Mbit/s cable modem connection from Welho.
As background information, I wanted to know how long it took for packets to travel to Google data centers compare to my ISP.
TCP/IP packets travelled several additional hops compared to the local ISP case. First they were beamed to Sweden, adding 10-20 ms to the roundtrip time. From there, they were routed to an unknown datacenter, possibly in UK or continental Europe.
All in all, the roundtrip time for Google DNS wasn’t bad, around 50 ms (see below), compared to 8-10 ms for my local ISP (not shown):
UDP roundtrip test
A side note: The media was in a frenzy when it was announced that Sweden is allowed to monitor all network traffic flowing through their backbones. At least until Google opens a data center in Finland (which is under construction), the Swedes can easily log DNS queries made by Finnish internet users through Google.
Next, I used the DNS Benchmarking tool developed by Steve Gibson. It does exhaustive tests to find out how long it takes for the DNS servers to return both cached and uncached records. I compared my local ISP, OpenDNS and Google:
DNS Benchmark by GRC
My local ISP was twice as fast (~100 ms vs. ~200 ms) when serving uncached records, and around 5-6 times faster for cached DNS records (8-9 ms vs. 50-60 ms).
Next, I wanted to see if changing the system-wide DNS setting affects the browsing speed. The test case was very simple: reset all caches, open yahoo.com and record time spent in DNS. For this test, I used the excellent Fiddler HTTP Debugging Proxy.
Using my ISP’s DNS, name resolution time was around 300 milliseconds. Here’s a typical result:
Time spent in DNS (local ISP)
When I changed system settings to Google’s Public DNS, I noticed a difference:
Time spent in DNS (Google)
Using the Google DNS Public Service increased name resolution time almost by a factor of 10x during actual browsing.
Clearly, Google Public DNS isn’t competitive in performance at the moment.
3
Dec 09
Ambiguous dates – why can’t we just agree on standards?
Lately, I have noticed the increased use of this style in presenting dates:
Wired News home page
I have concluded that replacing the slashes with dots is just a typographical fad. A very confusing one. Maybe I’m wrong. Maybe it’s a standard. I’m not sure.
Being a developer and knowing how hard international date formats can be, my brain is trained to spot oddities. I can perform correct conversions back and forth based on the current context.
Unfortunately, I can’t trust my own heuristics and instincts in all cases:
"My Brain Hurts" by Koushik Dutta (Seattle, WA)
The 12.01.2009 is actually 01.12.2009, or vice versa, depending on where you live.
The site is hosted on Blogger.com. I wonder is this ambigious formatting decision made by the page author, a custom template or by Blogger, now owned by Google?
If you insist on using non-standard date formats, could you at least try to be consistent.
27
Nov 09
Lost my life inside N900 – sudo’ing it back (with a blessing from Nokia)
Errata for my previous post: The Nokia Updater didn’t brick my N900 test unit. The gloomy morning greeting was caused just by a drained battery.
Nokia Software Updater isn’t supported on Windows 7. It just fails:
Nokia requires that I use either Windows XP or Windows Vista. Fortunately, I had a spare XP virtual machine lying on my disk, and managed to reinstall the system software.
Unfortunately, this didn’t clear the user data from the device. How… unexpected! Well, you could call this a feature, or a blessing, depending on your situation. Now you don’t have to hassle with backuping and restoring your Maemo device every time you do an OS upgrade.
But for me it’s a curse. I really, really want to erase every bit of personal data on this device. I synced it yesterday with my Outlook, and now it seems to contain every bit of both my personal and work life.
I sent Nokia guys several e-mails requesting assistance, but haven’t got any response yet. *
After trying out things by myself, I’ve figured out that there really isn’t a simple command to erase all the accounts, passwords, logs, pictures and what not.
Since I am fluent with Maemo, I’ve decided to install root access and SSH on the device, and start digging within the file system.
I so wished it wouldn’t get to this. I wished that Maemo 5 would be mature enough for the average user. I pretended to be one, until now.
rm -rf, here I come!
*) Got just official response back from Nokia. They confirmed my suspicion: there’s no GUI command for removing all personal data, and regretted that N900 is still a “hacker device” in some respects. I was instructed to use rm -r .*. Hint: choose your working directory carefully! 
27
Nov 09
N900 bricked by Nokia Software Updater?
In the morning, a very dark N900 was waiting on my desk. When I left it in the office yesterday, it was still very alive with the Nokia logo and a USB icon on the screen.
The instructions tell me not to disconnect or abort the process, or I’ll break the thing.
But I have to return it back to Nokia today – other reviewers are waiting for the unit.
I resorted to the manual for guidance: “Read the documentation stored on the device”. Well, that’s quite difficult now, but thank’s for saving some paper.
Quite a conundrum here.
(Errata & follow-up)
26
Nov 09
Stuck with the N900 review unit
The first Maemo phone has finally gone through our tests, and the critical review is done.
Tomorrow the unit goes back to Nokia, but first it has to be re-initialized. So, I launched the Nokia Software Updater and started the process as usual:
Alas, the progress bar seems to be stuck. The estimate “15 minutes left” hasn’t changed at all in 2 hours.
Oh well, I’ll leave it crunching for the night and disconnect it it the morning.
24
Nov 09
Linkpost: iPhone malware, N900 and WinMo depression, Chrome extensions
Mainly mobile topics, with some Microsoft and Ruby filling:
- Spotify now runs on Symbian in addition to iPhone. No news on Silverlight port for Symbian at last week’s PDC.
- Nokia sent a batch of N900’s to the Finnish press just before PDC. Haven’t had a chance to play with our test unit yet personally, Ilari has – with mixed feelings. Perttu Pitkänen (Digitoday, It-viikko), thinks its “sturdy” and “beats iPhone in multitasking”, AfterDawn likes the performance but dislikes the apps and limitations.
- Joe Wilcox writes in his PDC09 summary, that Microsoft “mobile phone strategy is a disaster”. Couldn’t agree more.
- Expression Web Service Pack 1 has been released. Mostly bug fixes, improves PHP editing (not something you would expect in a Microsoft product).
- Jailbroken iPhone and iPod touch users attacked by a new worm, this one sounds nasty.
- Google Hacking is always fun. This times PDF files printed with IE leak path data. Doesn’t sound that serious, though.
- WoW turned 5. Times flies!
- iPhone and Android make up 75% of mobile browsing in the US, according to AdMob.
- A new standard for content management systems is being prepared under OASIS. Seems quite enterprisey.
- JRuby is making progress, also on Windows. Haven’t noticed much enthusiasm behind IronRuby, though. InfoWorld report from RubyConf.
- And finally: Google opens Chrome to extension developers. Look out, Firefox.