Kilala.nl - Personal website of Thomas Sluyter

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Public and private parts of this site

2013-07-24 23:38:00

As I wrote earlier I have decided to clamp down on what is publicly published about our lives. This means that >80% of my blog has been turned into a private affair, with only work-related materials still being available to the whole world.

Now that my Macbook has crashed and I need to spend a lot of time waiting for the backups to restore, I have spent roughly eight hours updating my CMS code. It was an interesting learning experience and now this site has a basic login/logout functionality. Logging in will simply let you see the website in all of its original glory.

If I haven't contacted you yet about a username+password and you'd like one, drop me an email.


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Security measures all of us can take - part 2

2013-07-14 23:28:00

As a follow-up to my previous post on common sense I'd like to touch on Internet privacy. 

A few months ago I decided it was time to clean up my presence in social media. Using various plugins and a with a lot of patience I managed to clear out every post I had ever made to Facebook, Google Plus and Reddit. This decission followed after one-too-many privacy changes on Facebook and the realization that despite my best intentions I was still sharing a lot of information. I now regularly go over all of my social profiles to ensure nothing is "leaking out", as all parties involved have proven not to care too much about your privacy. 

What's more, is that I've come to reconsider my online profile. You know how we warn our kids never to give out their real names on the Internet? Or their address and whatnot? Isn't it ironic then, that I've been doing just that for well over a decade? Not only that, but I've kept a pretty detailed diary and have interacted with thousands of people through dozens of forums. I've used the same alias in all of those places, making myself very identifiable. 

Better late than never, but I've finally come to the decission to try and break down that online persona as well as possible. Wherever I can I've taken to changing my usernames and identifiers. That's one hint for people: don't use the same name everywhere.

A second point: on many forums it's not possible to delete all the posts you made. Most forums are of the opinion that providing an option to delete one's whole history is detrimental to both the discussions and to the content of their site. And of course they're right. So if you want to start culling posts you will either need to be selective and pick the worst stuff, or you'll spend hours upon hours manually deleting each and every post you made. Luckily there are tools to help you out, like Greasemonkey scripts that can automate browser tasks: to delete reddit comments, or to clean your facebook timeline. They're not foolproof, but it helps.  

Remember: just about everything on the Internet is forever. If it's not people making copies of your photos or text, it's companies! The famous Internet wayback machine regularly snapshots whole websites for posterity. And sites like Topsy.com shamelessly take your whole Facebook/Google+/Twitter feed and retain fully searchable copies on their own website. 

It's been said before and it'll be often repeated: think about what you post and to whom you make it available. Review your privacy settings on social media frequently and think hard if you want something to be shared across the globe. 

That's why I've decided to dedicate the public version of this website to my professional activites: work, programming, learning. All of the other things will be passworded and only available to myself and my family. 


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Security measures all of us can take

2013-06-10 16:47:00

Recently I've been on a bit of a security-binge at home. This blog post may have been tagged as "geeky", but as the title says I'll be going over a few things all of us should be familiar with. At least, that's my opinion... These days you're taking risks if you don't use these measures.

1. NFC security

Per this week, ING Bank are providing customers with NFC equipped debit cards. It's not optional, it's in every single card. NFC, Near Field Communications, is a technical term for what most of us will know as "contactless transactions": the chip card used in dutch public transport, or the ICOCA/Pasmo/Suica cards from Japan. In ING's case, this means that your debit card can now be used for payments, simply by holding your case close to a payment terminal. Payments under €25 will not require an authentication using PIN and payments are charged directly to your account. It is not a charge card, like Suica or OV Chip

Because NFC features will be featured in more and more products, now is the time to start thinking about securing your cards. Your bank card, your credit card (Visa also has NFC), your public transport card and of course also the access cards for the office! While many parties tout an effective range of 2-4cm for NFC, in actuallity there have been many test cases where NFC cards were activated over ranges from 30cm to several meters.

I'm calling it right now: the buzzword for 2014/2015 will be "crowd skimming".

crowd skimming nfc rfid clone steal

Miscreants will simply hide an NFC skimmer in a backpack and start walking through busy crowds. Imagine how many cards could be copied, or transactions could be made by walking around a train station or a music festival!

Protection is easy and I'm sure that by 2024 most wallets sold will come with this feature: shielding. There are many DIY projects online for aluminum lined wallets, but they're also for sale. DIFRWear is a famous example, as is the dutch designed Secrid. Instead of spending €25-€50, I got a Safe Wallet from Marskramer at a low €2,99 (free shipping)!

2. Passwords

Everyone's heard it before: "don't use simple passwords!

Make your password hard to guess, don't use the same password for multiple accounts, change your passwords regularly. Most people know these rules (best practices?), but many don't adhere to them. And I understand! They're a hassle! Every few months I need to manually visit over fifty websites to change passwords and it's a pain. But that doesn't mean you shouldn't do it!

Luckily password managers will make life a lot easier for you. There are many to choose from and I went with 1Password. At its most basic, 1Password becomes your safe storehouse for all your passwords (and other confidential information). But where it shines is its browser integration, that will allow you to automatically login to your websites. For example, I visit Facebook.com and ask 1Password to login for me, which it does. Done!

The great thing about this, is that it makes complex passwords effortless for you! Have a hard time remembering a sixteen character, random string of letters and numbers? You won't need to, because 1Password fills it out for you. And access to your password vault is obviously protected by one very strong password, hence the name of the product :)

If you'd like to take your passwords with you on the road, for use on another computer, then 1Password can provide you with a smartphone app for iOS or Android. You'll always have all your passwords with you, safely encrypted and protected.

EDIT: The newly announced iCloud Keychain will be another good option for Mac OS users. And of course Keeppass is cross-platform and free. Also, be sure to check out the different managers as some are not without issues.

3. Multi-factor authentication

The problem with username-password authentication is that in many cases your username is plainly obvious. Often it's your email address, some permutation of your name or a nickname that's out in the open. That leaves only your password as the true secret and as was discussed at #2, often it's not a very good secret to begin with!

One solution to this problem is to add another factor to the authentication step. Next to using something that you know (name and password) you'll often see the use of something that you have, like an OTP token.

Many websites will allow you to enable two-factor, or multi-factor authentication. E-Banking sites have historically used random number generating tokens, or "calculators". But these days it's becoming common for more and more sites and applications. Facebook, LinkedIn, Google, Wordpress, Evernote, all of them let you use a smartphone app or they'll send you an SMS with a one-time code. Thus your smartphone becomes the "something you have" factor, which will generate codes for you. 

Personally, I've come to use Google Authenticator for many of my accounts. It's free and it's open source. Best of all: while it may be Google in name it does NOT run on Google servers. It's 100% between your phone/PC and the account in question. Google Authenticator is wonderfully flexible, insofar that it can be integrated with any service you can think of. Obviously it's being used by websites, but it can also be integrated into applications (like Evernote) and into PAM-compatible Unix services so you can use it for your SSH logins.

4. Whole disk encryption

Most of us don't give much thought to all the data stored on our computers, but to be honest: for most of us our whole lives are on there. Emails, documents, photographs and plenty of secrets. Bank details, credit card numbers, passwords and confidential data. Is it really a smart idea to leave that stuff unprotected, to be read by anyone willing to steal your stuff? No.

That's where whole-disk encryption comes in. This solution renders your whole hard drive unreadable, unless you have the password. Your computer won't boot, nor can anyone go through your files, with the password. In this day and age most computers are also fast enough for you not to notice any real slowdown thanks to the encryption. 

There are plenty of commercial products available, but there's also free stuff out there. TrueCrypt is free and open source and is cross-platform (Windows, Linux, Mac OS X). BitLocker is included with some versions of Windows and FileVault comes standard with every Macintosh since Lion / 10.7. 

EDIT:

Darn, I'm not the first one to coin "crowd skimming". This blog used it earlier, but to refer to copyright trolling bittorrent users, sueing them for damages.


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Successes from coaching

2013-02-24 20:52:00

Keuzes Maken

For the past few months I've been undergoing personal coaching, by Menno. Today we simply spoke about the successes I've booked over the past few weeks. All of them were brought on by actions I undertook based on the coaching i've been receiving. Each of the following was an 'action point' or 'todo' item from our sessions. 


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Structures: solidifying goals and intentions

2013-02-10 11:54:00

My dou, with motto

One of the recuring themes in my coaching sessions with Rockover are "structures": things you put in place to act as reminders of something that you need to (or want to) change. I've talked about one of'm before. In order to solidify my new motto, I've given it the same treatment as the previous one that I took in: both adorn the inside of my dou, the torso armor worn in kendo.

Sure, my kanji look crappy, but it will serve its purpose: to remind me of what I want to achieve at the beginning of every training session, class and seminar. 

EDIT:

That photograph reminds me: the Agyo omamori in my dou is officially way overdue on being returned to the shrine it came from. We bought it in Nara in october of 2011 (photo of the temple), meaning that we were supposed to return in three months ago. Since I'm not religious I don't believe I'm calling down any bad luck upon myself, but then again I do value tradition :) Maybe I should drop another email to the dutch shinto shrine


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Coaching: better than I expected

2013-01-12 13:45:00

Quite a while ago my dear friend Menno started a career in personal coaching. He's still a civil engineer, but as a side business he runs Rockover Coaching which is based on the co-active coaching formula. It took a lot of hard work, but he's now ready to start working with clients. As part of his startup year, he asked me whether I'd like to be a 'victim' and I gladly accepted. I may have an ingrained mistrust of coaches, but I know I can trust the guy who's been my best friend for 27 years ;)

Over the past few weeks we've used a lot of different techniques to explore various topics, such as:

So... After almost three months of weekly coaching I have to say it's a lot more fun and interesting than I thought before starting with Menno. I had a few other touch-feely courses (through work) before this, but none of those were as comfortable as this.


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Just hanging around

2012-09-29 16:02:00

A keikogi hanging in a tree

Today's been great. Class was good exercise, we had a nice lunch and now I'm just hanging around a bit with Dana. Reading, writing, cleaning a bit. The weather's glorious too :) And now it's time for a bath with Dana! 


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Sure, let's give it a try

2012-06-16 20:01:00

HG Sportkleding luchtjes

It's not often that Marli gets excited about cleaning commercials. While I was making tea in the kitchen, she excitedly "Ooh! Ooh! Ooh!"s me back into the living room and rewinds the PVR. It was an ad for HG's detergent for sports clothing

As we all know kendo stinks. Kendo armour gets a bit smelly, kendo gloves can get pretty bad and my keikogi (the jacket) is godawful every single week. Hence Marli's enthusiasm. Let's give it a shot then :)


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Kicking my own ass and then getting it kicked as well

2012-04-18 10:34:00

Over the past few days my mood had been getting increasingly bad. I was on edge, tired and just not relaxing. I think that a lot of that can be attributed to my recent interest in CC:TA. In my earlier blog post I wrote the game was addictive and it is: it'd become too easy to just waste a whole evening staring at that screen. "Let's raid a camp or two. Okay, I'm through my CP, so let's do base maintenance. Okay, now what? 45 minutes before I can anything else. Okay, let's read the forum and do some diplomacy!" And so on. All the reasons why I never got into WoW.

Then, last night I was this -> <- close to skipping kendo practice again, because of my foul mood. And as I sat there, watching the CC:TA screen, already five minutes late for leaving, I decided to quit the game. I'll set up my base so my alliance mates can raid it and then I'm out. Fsck that, I've got plenty of better things to do.It's a fun game, but nothing more than that.

Marli helped me greatly! "Do I need to push you to go?" And so she did. She quickly helped me pack all my gear and sent me on my way to Amstelveen. Gotta love that girl! ( ^_^)

Luckily I was only a few minutes late and I was just in time to join in with the warming up. After that followed kihon, followed by geiko and more geiko. The group was smaller than usual, but there were many high-level kendoka, including three from the dutch national team! I bowed out from the second round of geiko (the last twenty minutes of class) as I was feeling exhausted and was afraid I wouldn't make it back home.

Pointers I received from several of my sempai:

Thanks to Chung-sempai I now also know what a mouse feels like, when toyed with by a cat. During geiko, with every strike of mine, she darted aside and retaliated with two quick strikes and a giggle. I couldn't help but smile, while getting my ass handed to me.

Also, I don't think we've ever introduced ourselves so I don't know his name. One of the young guys who started in bogu only three weeks ago. He clocked me on my elbow with his tsuba. Twice. Hard. Man that hurt! ( ^_^) Arm's fine today, no worries.


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Doesn't that hit too close to home?

2011-08-14 10:26:00

work environment = lab environment

From Dilbert, of course.


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Every journey starts with a single step

2011-01-23 09:25:00

I have to say that starting something completely new is very thrilling. Though I have to admit that sometimes it's exciting to the point of panic.

Case in point: we will be soon taking Dana on her first airplane ride ever. In preparation for our long vacation in Japan we wanted to make sure that Dana doesn't go nuts on a plane, so we thought we'd try a day in Copenhagen which is only a one-hour flight instead of twelve. For some reason the idea of taking Dana on a plane fills me with dread, even going so far to giving me a real panic attack. I have absolutely no clue why, because it's all very safe and sound. I need to go over my own thoughts to try and find out what the heck is up.

Putting that particular case aside, I really do love starting new things from scratch. It's quite refreshing to be a blank slate, being forced to learn something from the utter and complete basics. This is why I loved going back to college, why I loved learning golf and now it's why I greatly enjoy kendo.

It's interesting to see that in kendo I tend to make the same mistakes I did in golf: I cramp my arms and I still try to put force on both of my arms instead of only on my left arm. As is explained on this terrific website:

"Perhaps the most common mistake of beginners is to use the muscles of the right arm to swing. Ask any golfer what happens if you try and use the muscles of your right hand in a golf swing. The swing will go wild, you won't hit your target, and you'll hit very hard with no self control. This not only looks terrible, but will piss off your opponent as well."

I do admit that for the first time in learning something new I am actually daunted by the task at hand! The journey to learn kendo leads up a huge mountain and right now I can see the whole trip I'm supposed to take. I should really only focus on the first few steps though, because the enormity of the task may lead me to two of the four shikai: doubt and confusion.


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A lesson I'd do well to learn

2010-04-16 05:52:00

... not because I'm going to work in Japan, but because even in the Netherlands it would be quite, quite helpful.

Quoting Hiko who is giving tips to survive in the Japanese workplace.

There are times in our lives that we have had the joy of letting rip with a phrase of self righteous condemnation like [this is bulls**t!]. Look back and remember those times. Savor them, and cherish them knowing that so long as you are in Japan and wish to remain employed and an unstigmatized non-social-outcast, you will never be able to have memories like ever that again, unless the story ends "and so then I was fired, and left Japan and overall I was a better person for the experience". Japan is a pathologically non-confrontational culture. All that bottled up indignation and rage tends to get released as passive aggression, or internalized into digestive-tract disorders. The best solution is to learn to undo your reflex to want to butt heads and learn how to resolve conflict the Japanese way.


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Tips from Stef Heinsman, our director

2007-08-31 11:40:00

On the 30th of August 2007, Stef Heinsman opened the new academic year at Instituut Archimedes. All freshmen for the tweedegraads docent course attended an introductory meeting, welcoming them to their new school.

Surprisingly, our director/rector Stef Heinsman had some interesting tidbits for the crowd. It wasn't the expected, useless ramble :)

The three most important lessons from his own past:

  1. Always attend lectures and sessions.
  2. Don't postpone your work.
  3. Be stubborn when you can afford it.

By attending lectures you build a solid relationship, both with your teachers and your fellow students. You will also remain emerged into the whole spirit of school and teaching, ensuring your continued enthusiasm.

By not postponing your work, Stef is convinced that you will build confidence in your own competences. By taking the same tests and projects as your fellow students, at the same time, you will realize that they're in the same boat. Things may be hard for you, but there are other people in the exact same situation.

At times you'll be convinced that your own approach to a certain situation is the best one. Don't feel forced to take the teacher's approach and verify your own opinions. Become autonomous, allowing you to do your own work when you need to.

Combining these three factors will help you with your motivation. It's what you're going to need when things get a little rough around the edges.

In conclusion, Stef also asks us to take care of our selves. Don't lose your health, don't burn out and make sure that things are fine at home. Because the people at home are your strongest foundations.

He also suggested that you should teach something that you enjoy. By doing that you'll not only convey knowledge, but also enthusiasm!


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Big career changes: talking to the experts

2007-07-10 23:47:00

I can heartily recommend anyone considering a career switch to go and have a chat with people who work in their aspired field.

I made a little visit to my old high school this morning, to talk to their HR guy. He gave me a lot of valuable tips and suggested that a part-time study would indeed be the best and safest option for me. He indicated that it would be nigh on impossible for me to get a zij-instroom position, due to my lack of experience.

He also suggested that I go have a talk with the CWI (Centrum voor Werk en Inkomen), the part of the dutch government charged with work and job security. He reckoned that I might strike a lucky deal with them, getting a subsidy for hours I didn't spend working for Snow. In order to make time for my education I'd need to cut back on my working hours (and thus my monthly wages) by about 40%. This grant might help cover for at least part of the money I'd miss out on.

Tomorrow I'll also make a phone call with the CO of another high school. His number was given to me by my father's girlfriend who happens to work with the fellow. I'm curious if he has some other useful tips for me :)


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Big career changes: where do we go from here?

2007-07-10 23:34:00

Now that I'd decided to become a teacher, it left me with even more questions (duh). Which subject would I teach? At what kind of school? What kind of education do I need? Where do I study? How will this fit in with my job? Will I even be able to keep my job? OMG, will we be able to pay our mortgage and still have food on the table?! ONOZ!

Stuff like that.

Well... I quickly decided that I'd like to teach english or math at a high school level. I can wax lyrically about both subjects and both fields offer me with loads of new stuff to learn and explore.

So... How do you go from having a completely unrelated job, to being a teacher? Here's how... (mind you, all of this applies to the Netherlands).

You start out with two options:

1. You take up a part-time or full-time college education. (deeltijd or voltijd in dutch).

2. You take up a part-time teaching position and follow additional classes to become a real teacher.

This second option is called zij-instroom in dutch and really is only an option if your ambitions lie in teaching the same field you worked in. So for example, I could get a zij-instroom position teaching Comp Sci at high schools, whereas a biologist could start teaching Biology. Zij-instroom however requires you to have real and provable experience in said field, including the degrees that come with it. You will also need to take an entrance exam because they won't let just everybody start teaching. Should you be accepted for zij-instroom, then you'll get a two-year teaching permit, which is directly connected to a contract between you and the school in question.

Anywho... What with zij-instroom not being an option for my two chosen fields (I have neither a degree, nor work experience in english or math) I have to opt for the longer path. Getting into a full-time education (voltijd) really isn't an option for me anymore: I wouldn't have any income, I'd be bored stiff and I'd be in a class full of eighteen year olds. Which automatically guides me towards a part-time education.

Luckily every college in the Netherlands offers deeltijd educations for professionals looking for a career switch, or an upgrade to their knowledge. The Hogeschool Utrecht offers teachers educations that are actually reputable and it's close to my home as well! Now all that remains is to convince my employer to let me work either three or four days a week. *gulp*


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Big career changes: prelude

2007-07-10 22:25:00

This blog post was made invisible initially. It has now been made available to the Internet at large. Sorry for breaking continuity :D

Back in April, I felt like crap. Then, in June, it came back. Now, with the start of July I've made my decision:

I'm getting out of IT.

That day in June something snapped inside of me and I decided that I could no longer carry on working as a sysadmin. The work no longer motivates me, nor does it offer me some shine of glamour. I know that, while there are still endless, uncharted seas for me to discover, this field no longer holds a challenge for me. I know that whatever I'll need to learn, I'll be able to do so in a few days. Lather, rinse, repeat, until I grow old.

No thank you.

No longer will I be shifting bits and bytes around, being a faceless peon in a huge corporation. No longer will I be burning midnight oil at the altar of Unix.

Instead I will make difference in this world and I will be of use to the general public. I will try to educate this world's children, nudging them into directions they might otherwise ignore.

I have decided to go into education and become a high school teacher.


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