The internal actuator arm and rotating disk of a harddisk.

I recently completed my Bachelor’s degree at the IT-University of Copenhagen. My Bachelor’s project focused on the exploration of an LSM-tree on an Open-Channel SSD. While this sounds like nonsense for most people, including myself before I started this project, it contains some valuable insight into how modern SSDs work. Lets first look into some history.

In 1956, IBM introduced the first hard disk. It works by having a physical actuator arm writing bits of data on a physical rotating disk internally. As HDDs have complex geometry consisting of layers of circles, the HDD abstracts away physical locations on the…


In 2016, Yahoo was ordered to scan every incoming email to their platform according to ProtonMail. And this time, it wasn’t for monetary gains. This time, it was due to a court order by the NSA and FBI. Yahoo was legally forced to change their spam-filter also to detect keywords defined by the federal government and to notify the before-mentioned authorities.

So what does this mean? 500.000.000 users worldwide are presumed to be guilty and are being monitored without a court order. That also includes foreigners, with no real link to the United States.

This monitoring is genuinely insane. Internet…


Investing money is a great way to fight inflation and grow your savings. Therefore I’ve written a few tips for new investors.

1. Find out how much you are willing to risk

The world of financial investments is huge. You can typically invest in equities, bonds, contract-for-differences, futures, options, and currencies. Each product has its own risks and benefits. As a new investor, you should find a trading product, that you are comfortable with.

Bonds are generally safe and risk-free — especially European government bonds. When purchasing bonds, you technically purchase a part of a loan, so that the lender owes you the money. This entitles you to the interest…


I’m pretty sure you’ve heard from multiple sources now, that the green lock at the top of your browser is good. And that sites without them are bad. But what does it really do? And why are everybody so hyped about it?

Whenever you visit a website, you are using the HTTP protocol. HTTP is short for HyperText Transfer Protocol. This protocol allows transfer of so-called HyperText documents.

HyperText is just plain text, but where you can jump between different pages or sections of the text. Basically, the concept allows so-called links to other pages, just like any website today.


You might not even know. Internet Service Providers, E-mail providers, and social media are tracking your every move on the internet. And they are not alone. Behind them are thousands of ad companies. These companies keep track of your interests, your opinions, your sexuality, how you perform at work and the list is continuing into infinity.

How? Every time you visit a website — fx. a news website, advertisements might be injected into the page. Social media plugins like “Share on [Social Media]” are typically also injected. Each time this injection occurs, the ad-provider or social media is notified.

Therefore…


A few days ago, the creator of Laravel Taylor Otwell published a story here on Medium about how he works. If you haven’t read it, you can read it here.

The story inspired me to do the same. I have a shifting day, with a lot of interesting aspects.

The Average Day

Since I study and have lectures on varying times, there is no such thing as an “average day”. Most weekdays start out at the IT-University of Copenhagen at 10:00 am. I live roughly 60 minutes of walking and commuting from the university, so I happily accept the days with lectures and…


That was harsh. I’m sorry, but it’s most likely true. I’ve worked at several different tech companies, and met several different developers. Every developer has bad tendencies of their own.

I’ve met people, who wrote too big methods, people picking wrong data-types, people using floating points for currency and people that haven’t written a unit test since .. ever!

Not that I’m an angel either. I’ve written a lot of bad code, but in the last few years, I’ve written exceptionally good code, since I follow some basics rules.

The ideal method should have the following traits

  • Small. The smaller…


Being visionary is a key ingredient in succeeding as an entrepreneur.

Or so I thought. I’ve always worked with people with ideas and visions. People figuratively being on the moon and flying around in their space ships in a universe of ideas. I’ve always been the complete opposite of that. I’m looking one task ahead and I never think any further. I’m not visionary at all.

My experience in the tech-business is one hell of a ride, and I’ve seen and learnt things. The most phenomenal is vision. The most visionary tech-people are the most ignorant and hopeless entrepreneurs. …


Lately I’ve been thinking about my power usage. I am the one paying the power bill, so every turned off lamp saves me a tiny bit of money. But even a tiny bit of money can grow big.

It made me think about my home office, my TV and basically every lamp in my apartment. Over half of the lamps have already been replaced by low power LEDs and almost all my electronics are wired to be shut off when the primary device is turned off. No standby power.

But the iMac is still in my mind. It takes so…

Niclas Hedam

PhD Fellow at the IT University of Copenhagen. Interested in security and data systems.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store