2017, The Year of Certificates

I obtained 5 certificates and cleared 6 exams in 2017, AWS solution architect, developer and SysOps in associate level, Scrum Master and TOGAF (part 1 and 2).

It has been quite an achievement personally, taking into account a full time job and family with two little monsters.

I have written already about AWS exams but for TOGAF I studied about 3-4 months, 5 hours a week roughly. It’s a very dry subject and requires a lot of memorisation. I might write about pros and cons of TOGAF as a framework in general later but I would suggest everyone who calls themselves an architect in the IT world take this certificate. A Udemy course on the subject was also helpful.

With any certificates you have to memorise a lot to pass the exam; it’s not just about knowing or understanding the subject. This is the part I have problems with and the reason behind not having any certificates after working in IT for many years! This year I thought I will give it a try for a change!

In order to pass a certification exam and truly understand a subject you have to find the right balance between memorising concepts and learning them by heart. This is very important otherwise you get certified and never understand the subject matter in detail. Your certification will just become a worthless piece of paper.

togaf9-certified

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Bitcoin 101

I am sure you have used your credit cards for online shopping, you enter the card number and click submit. Some of you might even have a Paypal account in which you use your email to make a payment. Your Paypal account is again linked to your credit card or bank account.

There is still a centralised governance which is the bank. Every transaction goes through the banks. There is a central “ledger”. We “trust” the credit card company to keep the transaction and our details safe.

In 2008 an article was published by someone called Satoshi Nakamoto and Bitcoin was born. He/she/they proposed a relatively new system of currency and implemented that into a software system and then we heard nothing from them after 2010. They just vanished.

Bitcoin is a digital, de-centralised currency. What does that mean?

Well it’s digital so there is no physical money involved, and it’s de-centralised which means no bank or governing body controls it and it’s managed by those who use it. Nobody owns the Bitcoin network much like no one owns the Internet.

Instead of a bank recording transactions in a centralised ledger, all Bitcoin users keep the same copy of the same ledger; as a result it would be extremely hard to mess with the system because everyone has to be in sync.

This public ledger contains every transaction ever processed in the system and every user has a copy of that. It’s an example of triple entry bookkeeping system.

But how Bitcoin is generated?

Unlike real money that is usually backed by gold, Bitcoin is backed by supply and demand and is created using a process called “mining”. This is an analogy to gold mining in which you do work and get rewarded with gold.

Mining is the process of spending “computing power” to process transactions, secure the network, and keep everyone in the system synchronized together. Bitcoin mining provides a reward  in exchange for useful services required to operate a secure payment network. Anybody can become a Bitcoin miner by installing the correct software version.

So what’s Bitcoin good for? The following are some of the benefits of Bitcoin:

  • Cheaper to transfer money as it goes directly to another person
  • It can work across the globe. Not tied to a government or country
  • No currency conversion
  • Not affected by currency fluctuations
  • It has been designed to have a limited number of bitcoins (maximum 21 million) so there will be no inflation

From a user perspective, Bitcoin is nothing more than a mobile app that provides a personal Bitcoin wallet and allows a user to send and receive bitcoins with them. This is how Bitcoin works for most users.

There are different ways to obtain bitcoin:

  • Mining
  • Sell products and accept Bitcoin
  • Buy Bitcoin directly from Ebay

But Bitcoin is not without problems. Let’s look at some of its problems:

  • Degree of acceptance – Many people are still unaware of Bitcoin. The number of businesses using Bitcoin are very small compared to what it could be
  • Volatility – The total value of bitcoin vacillates a lot. The price went from zero in 2010 to 5600 USD few days ago
  • Still new and under development
  • Some have profited from being involved early – unfair advantage
  • It is legal at least in Australia as long as you declare your profit to ATO but it’s a perfect tool for criminals since it doesn’t need to be tied to a person.  But it has been used in criminal activities as much as credit cards have been used

Some people say bitcoin is the 21st century version of gold without storage costs. Some people call it a fad, hype or even fraud.

Bitcoin is a big deal in computer world and in ecommerce; everyone is jumping into it and it’s growing. But will it ever become a major payment network? If we could get bitcoin to work or something like it, if we could trust a digital currency, it has a lot of potentials to transform our economy for better.

In the meantime I urge you to try it for yourself.  Go ahead and install the bitcoin app, create your wallet or watch some Youtube videos about it. You can even buy some bitcoin from Ebay and see how it works.

It’s going to be fun!

Why I will never install Linux on my Mac

These are the reasons why I will never install a Linux on my personal Mac or PC as the main OS, at least for now.

I have to stress that these are more of a taste and the way I use my computers and might not be an issue for other people.

I also have to say that I work with linux servers in my day to day work and love them but in the desktop world I doubt Linux has a place yet. I even have an Ubuntu desktop on another computer at work that I use for some tasks.

Now:

  • As long as there are articles in the Linux world starting with “how to install” that means things are not yet user friendly
  • All I need from linux is a terminal that I have in Mac or I can ssh to a remote linux machine
  • Linux does not have Facetime
  • Skype is dodgy in linux. You will never know whether your audio card will work in the next release of linux or not!
  • Many apps do not have proper/strong counterparts in linux or if they have it is dodgy or buggy: Libre Office crap; different messengers all buggy, either video or audio not working properly; graphics editors, nothing close to photoshop; sound editors, don’t even think about it; Evolution/Thunderbird vs Outlook haha…
  • You always have to look for the drivers. Whether my webcam, printer, this and that work in linux or not.
  • For simple tasks you have to waste your whole day on Internet searching and finally someone suggested on their weblog that you have to put a flag on a config file for that thing to work!!

I didn’t mean to hurt anyones feelings, just for a bit of laugh 😉

Tablet as Photo Frame

I long wanted to have a good photo frame. Then from somewhere came the idea of using a tablet as one. After deciding for months on what tablet to get finally I went for a cheap no-brand android tablet under $60. It is a 7″ Android 4.0 from ebay with 512 RAM, 1.2 GHz CPU, 4GB internal memory, wifi, camera, etc.

Using a $2.5 slide show application from Google Play I can show photos from network. At this time we have around 35,000 photos sitting in the NAS to be viewed!

For mounting I purchased a PadTab which is a brilliant mounting idea for vertical smooth surfaces (i.e. fridge)

This is not just a photo viewer. I have also installed few useful apps and widgets to show calendar, weather, etc that we use when we are tired of seeing photos!

We can also quickly check emails or facebook while standing although hasn’t happened yet!

Total cost: $71

My wife was initially sceptic of the whole idea but now she seems happy about the final setup. I also have to confess that at first I wasn’t quite confident of a tablet with that price range and 800×600 resolution but it is producing pretty decent images.

2013-08-18 12.52.34

Clean rebuild to Mountain Lion

As this was my first Mac, I had done lots changes here and there to experiment and it was time to start afresh. Also I wanted to get rid of stupid packages and applications that I had installed in the past few years (including Xcode!)

When it comes to MS Windows installation I am an expert but in the Mac world I am hopeless.

Searched the Internet for ways to cleanup the hard disk and start a clean OS and saw different ways of doing it by different people.

The best way that works for me was:

  1. Shutdown
  2. Press cmd+R and power on (You can also restart and do this)
  3. System goes into recovery mode
  4. Format the entire disk
  5. Install the OS from Internet

This saved me from creating boot disks, etc.

See: http://support.apple.com/kb/HT4718

Build Light

A build light is rather a new (?) thing teams do to indicate their software build/test status. It has become very common in Agile teams. I did one for our project although not entirely Agile but it indicates the status of our builds being made in our in-house build server.

Read more about it in wikipedia: http://en.wikipedia.org/wiki/Build_light_indicator

I purchased the light from http://www.delcomproducts.com which sells them very expensive! A USB RGY LED light (http://www.delcomproducts.com/productdetails.asp?productnum=904007)  costed me (our project) around 120 AUD to reach Sydney from US! Quite an expensive light!

If you are into electronics you should be able to make one easily I suppose. I am not really a hardware person and also have no time for it.

Anyway the light arrived quickly with no documents attached but everything can be found online. In Windows there is a command line application “USBCMDAP.exe” that can quickly turn it on:

USBCMDAP.exe 0 0 101 12 1 0 #green on
USBCMDAP.exe 0 0 101 12 2 0 #red on
USBCMDAP.exe 0 0 101 12 0 3 # all off

my build light

Now all you need to do is to read the status of your build/test/project/whatever and turn this on/off accordingly.

There are drivers for different OSes and hardware information in their website if you want to get more serious.

If you found a similar light but cheaper (together with software) then let me know!

My RaspberryPi

My RaspberryPi

This is my latest toy. Although it is one of the cheapest but one of the most interesting ones!

I bought is from au.element14.com in Australia and ordered a case off ebay that I broke while putting it together! It was one of the transparent ones and very fragile. You do not really need a case for it.

I will not go into details of how to set this up as you can find a lot of info on the web.

Just a few notes:

  • For me copying the image to SD took about 10 minutes.
  • Power is through the USB port of my router
  • The desktop Linux is quite responsive but do not expect much from it
  • I enabled ssh and connect to it only remotely. Lynx browser is of some help sometimes !

I am planning to use it as a proxy/firewall in front of my router so currently installing a proxy server into it. I will try to use GPIO ports in the future.