Posts

Preamble Recently I became nostalgic and fascinated with stuff from the past, so I decided to create a Vagrantfile to work with FreeBSD1. Why FreeBSD? Because as a developer, I really like Docker and I started looking in the past to find its historical birth: in fact, as a concept, Docker is no so recent as you think, and I think it exists also because of the works of some other bigs from 80’, such as Poul-Henning Kamp2. Starting from its work and using a FreeBSD installation I did some experiments with jails, to understand better what they really are, how they works - how can you create what it will look like a vintage container - and why you should use them in a FreeBSD environment - at least, to learn something new. ...

A journey through the network - Layer 1 Before the Christmas holidays, I wrote an article about the network: yes. The network is that part of computer science that is no longer considered fundamental as it should, and I must admit that I learn it every day at my expense: as an old friend always says to me “the network is the concept on which everything is based, describes how the body works: after that, you can also become a gastroenterologist, but you will always need to know how the body works”. I think he’s right. As I was saying, I wrote an article about that: it’s a sort of overview and technical / historical introduction on the ISO / OSI and TCP / IP protocols. For those who missed the introduction, here the link. Despite my lack of experience, I promised myself, as far as possible, with the little time available, to retrace the various levels of the network from a theoretical point of view without going into too much detail, also trying to identify the most used commands, understand the level at which they operate and the functioning of the parameters supported by them. It took me a lot of time … but finally, the post on level one is ready. As a main source I use Computer Networks and TCP/IP Illustrated. In this article, I will talk about layer 0, the lowest in the ISO / OSI stack. Enjoy the reading! ...

A beautiful childhood I’ve never been a fan of videogames, neither as a child nor today: do not get me wrong, as many guys of my generation I also owned and played with the legendary PlayStation 1 (1995)1 and PlayStation 22 by Sony and the Nintendo Game Boy3. It was fun, but not so much as playing to videogames born a few years before I was born. In the 80s, there were not yet the powerful graphics chips that today can be found with a few hundred euros. How did the videogames work? It’s simple: without graphics. There were many textual games and in my opinion, for many vintage lovers, they would still be cool today. My generation has lost this advantage of literaly building with fantasy the world around a game. So, some days ago I found my self thinking back to Sheldoon Cooper that plays with the game Dungeon in the Big Bang Theory4, or to the kids of Stranger Things by Netflix, or to my father, to whom I gave an original Playstation 1 with the first TombRaider(s), and I asked myself how it would be possible today to play again one of those text games that were so popular in that decade…to the point of deciding to create one of my own. ...

Merry Christmas by nerds Here we are!! Christmas holidays are coming and it’s time to collect nerd greetings for nerd friends! In this article I have collected some of my favorites: starting from css to the most unhealthy c code in the world, I hope you enjoy these repositories / snippets / gist / sketch! Best wishes for happy holidays! CSS While I was looking for some cool css stuff to share with you, I found this fantastic gist that show the kind of magic a web expert can do with a bunch of css lines. Riddle: what do you see if you use IE as a browser? The answer after the preview! ...

The Doomsday rule A few months ago I came across the name of J. H. Conway: you’re wondering who the hell he is. Well, Conway is an English mathematician active in the theory of finite groups, knot theory, number theory, combinatorial game theory and coding theory. He has also contributed to many branches of recreational mathematics and he is the invention of the Game of Life. Ah, I was forgetting one last thing: he is currently Professor Emeritus of Mathematics at Princeton University in New Jersey1. Ok. let’s respect this guy but…what would I talk to you about? Well, in this article I will talk about a magic trick: the Doomsday rule. ...

A journey through the network - Introduction During the last year I understood one thing: sooner or later everyone should review network notions, so I decided to start writing articles about network fundamentals. As a main source I would use Computer Networks and TCP/IP Illustrated. In this article, I will talk about two important network architectures: the OSI reference model and the TCP/IP reference model. These two model has opposite characteristics, in particular: ...

Predix Machine and how to configure them In September, waiting for a contract proposal from the company where I currently work, I wrote a tool for the (more or less) automatic configuration of Predix© Machine. Predix©1 is the platform created by GE for Industry 4.0, powered by CloudFoundry2, to securely connect machines, data, and analytics to improve operational efficiency, help you develop, deploy, and operate industrial apps at the edge and in the cloud. As part of my internship I worked with the predix machine and I shared my work to the GE platform. GE mantains an open repository with predix tool ...

History We can date the birth of artificial neural networks in 1958, with the introduction of Perceptron 1 by Frank Rosenblatt. It was the first algorithm created to reproduce the biological neuron. Conceptually, the easier perceptron that you might think of is made of a single neuron: when it’s exposed to a stimulus, it provides a binary response, just as would a biological neuron. This model differs greatly from the neural network involving billions of neurons in a biological brain. Shortly after his birth, the researchers showed the world the problems of Perceptron: in fact, it was quickly proved that perceptrons could not be trained to recognize many classes of input patterns. To get a more powerful network, it was necessary to take advantage of multiple level of units and create a multilayers perceptron, with more intermediates neurons used to solve linearly separable2 subproblems, whose outputs were combined together by the final level to provide a concrete response to original input problem. Even though the Perceptron was just a simple but severely limited binary classifier, it introduced a great innovation: the idea to simulate the basic computational unit of a complex biological system that exists in nature. ...

Prelude Nobody ever tells you enough: you need to know the fundamentals. Ok - what am I talking about? I would rather limit myself to talking about computer science, something I really do not know about. Intro As this blog says, I’m an IT guy, and I reiterate that…I do not know anything about computer science. It is of course a fault of mine, at least in part, but I think it is also due to the time we live, the opportunities that surround me, the needs of the market, an endless amount of statistics about the world, the number people who live, the kind of people who are gone, the people who govern, the people who don’t, the available types of work, the new laws, the old laws, the borders, netflix-facebook-twitter-snapchat-telegram-instagram-pinterest-reddit-batman, certainly also because of Tweedledum and Tweedledee, and so many others things. I think I will go through some of the reasons that I feel are the most important ones to explain why I feel a lack of knowledge and why I am disappointed about it - more in general, about the global lack of fundamentals. ...

Recipe for a good meal A few months ago I started working with Golang to a proof-of-concept project using the amazing goa package (thank you atosatto for your advise): I omit the praise, I would only say that - imho - Golang it’s a very funny language to use for many reasons (stay tuned, I will write about Golang and my favourite packages). However, in this post I want to share a little piece of my experience about this project: the main ingredients for this recipe are Golang (in particular the goa package) and Docker - with some piece of Angular 4, nginx, and minor stuff. I excluded the storage part so the two elements of the boilerplate I will talk about live in separate container - you can of course orchestrate with k8… ok, whatever you want :P ...