Technology Blog Dietmar Zlabinger

Abstract Syntax Notation 1 (ASN1) is probably one of the worst encodings the Internet community has seen. Unfortunately this encoding is a key component in Internet security. Peter Gutmann, professor at the University of Auckland, NZ has not just written “How Not to Design a Crypto Protocol/Standard“, but also an ASN1-dump C-program.  I added a Java-script port written by Lapo Luchini to my homepage under http://www.zlabinger.at/asn1dump.

This version uses the top certificate of the TKK as an example.

In a test-setup I put 561GByte of data onto a 1 TByte harddisk. The first disk is formated with ext3, the other with xfs.
Here are the results:

df -h
/dev/sdc1 932G 561G 372G 61% /media/disk1_1T
/dev/sdd1 917G 561G 311G 65% /media/disk2_1T
mount
/dev/sdc1 on /media/disk1_1T type xfs (rw)
/dev/sdd1 on /media/disk2_1T type ext4 (rw)


Ok, by default ext reserves 5% for root-only usage, after removing that reservation ext4 ist still behind xfs:

tune2fs -m0 /dev/sdd1
Setting reserved blocks percentage to 0% (0 blocks)

df
/dev/sdc1 932G 561G 372G 61% /media/hd51_1T
/dev/sdd1 917G 561G 357G 62% /media/hd53_1T


Conclusion: ext3 reserves 15GByte more administrative space.
Of course, it’s not all about efficiency.

You may call it a PC, you may call it a low-cost Mac-Mini, Microsoft calls it an ULCPC – an ultra low cost PC, I call it an ideal home server. If your Linksys NSLU2 is great but lacks RAM and performance but you do not like the noise and power consumption of a standard PC, then read on.
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Most people have a number of computers and need at NAT device to connect them to the Internet, but in my case I had to solve the opposite problem – I had two internet connections, but just a single computer. With other words: I wanted the computer to be reachable from two different public addresses within two different subnets.
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The Drei “Internet to go” mobile broadband prepaid-package comes with an Option Icon72 USB modem. The original driver supports MS Windows, but of course, running it under Linux is much more interesting.

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Exif infos can be used to rename photos  For example, including the photos date and time into the filename helps to keep photos organized.

I use Irfanview to rename the files. My standard format is _-.jpg.

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At the time of writing there was an ongoing DVB-H trial in Vienna on UHF channel 36 (center frequency 594 MHz).

DVB-H is just a variant of DVB-T, so my idea was to use a DVB-T USB stick to receive DVB-H on my Linux-PC.
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You connecting flight is late. Ok, then let us kill time. First thing you need is a Nokia E61. The list of features sounds great, but when it gets to configure VoIP things become wearied.

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You can find photos taken with my Nokia N70 camera-phone at http://www.flickr.com/photos/zlabinger/ and photos taken with my Sony-Ericsson K800 at http://zlabinger.blogspot.com/ (old photos) and http://zlabinger2.blogspot.com (newer photos).
Dietmar