88th Monthly Technical Session
Every month HENNGE hosts technical talks on a range of subjects that our members wish to share with their peers.
On November 19th, 2021 we had our 88th session. As with most recent sessions, this was a fully remote talk done via Zoom. This time, there were six speakers on various topics.
How We Know It’s Us
Our first presentation was given by David. He talked about climate change.
According to a study, the climate has always changed in the past. But the point is we are creating a rapid and dramatic change.
He mentioned some of the possibilities as a root cause that came from nature like volcanoes or the Sun. Then, he introduced some insights into carbon like C12, C13, and C14 and mentioned the impact of fossil fuels on the environment as an actual root cause.
In the Q&A, we confirmed the importance of this kind of discussion, communicating facts and reasons.
Easy Autoscaling on AWS ECS
As the second speaker, Michael talked about AWS AutoScaling with ECS.
This time he focused on Reactive Autoscaling which reacts to metrics to control a cluster. Reactive Autoscaling has some policies like “Simple Scaling”, “Step Scaling” and “Target Tracking Scaling”.
We dived into Step Scaling Autoscaling by example. Then, we checked Target Tracking Scaling in Action. It can automatically maintain a target value like 250 requests/target. HENNGE Access Control implemented Target Tracking 1 and a half years ago and it works great.
For the rest of the session, he guided us by step by step tutorial of Target Tracking Scaling using our public terraform module.
Introduction to Ray
The third presenter Hideaki Yoshida introduced Ray which is an open-source distributed execution framework o provides an API for building and running python or machine learning applications.
Ray is built by a startup called Anyscale. It can simplify your architecture and lower your operating cost to build a scalable Python web service and it is useful, especially for a developer who knows more about machine learning than a distributed system.
A good thing is Ray allows us to use the existing libraries which we are using like Flask, aiohttp, or FastAPI. Python code needs to be adjusted for Ray depending on use cases like Task (stateless) and Actor (stateful). If the existing code base is used, for example, Flask, Ray can be a relevant technology we can introduce.
Compression with Burrows-Wheeler Transform
The fourth speaker was Raihan. He talked about Compression with Burrows-Wheeler Transform (BWT).
First of all, he introduced the basis of the compression algorithm. Then, he described how BWT works. The question is how can we decompress compressed data without knowing the original data?
BWT can achieve it with an important property and it even allows us to search data structure with suffix array. Since BWT has such characteristics, it is used for sequence alignment, image compression, compression of genomic databases, sequence prediction, and so on.
An Introduction to NFTs
The fifth presenter Kevin introduced Non-Fungible Token (NFT). NFT is a set of data or tokens that are used to represent physical or digital assets. It’s non-interchangeable and can represent ownership. It is getting popular lately but it actually started from the last decade in 2014.
The reason why it became so popular now is that it allows artists to increase potential income. From the buyer's or collectors' perspective, it allows the buyer to financially support their preferred artists and collectors to own a digital ‘rare’ artwork. Although there are some concerns like environmental concerns due to the huge amount of energy consumption for blockchain, its market keeps growing.
Solidity and Smart Contracts
The last speaker was Yera. He talked about Smart Contracts & Solidity. The smart contract is a program that executes when predetermined conditions are met. Its principle is easy. There is a notable analogy “a digital vending machine” coined by Nick Szabo and the analogy gives you the basic idea as you can imagine.
He introduced several programming languages to implement the smart contract and picked Solidity as an example. It is an object-oriented, high-level language for implementing smart contracts and he gave us an example code to define Coin.
Powering Video Conferences with OBS Browser Source
After all the talks, as usual, we opened our lightning talk slots for everyone. This time, our CEO, Kazuhiro Ogura, raised his hand and gave a talk about video conferences with OBS Browser Source.
When he does 1-to-N type of talks online, he misses the “feedbacks” from the audience. Previously, he used an external service to get feedback as emoji and he re-invented it to make his own service.
Whenever an attendee presses a button on his website, it sends an emoji to his server and popped up on his screen. To achieve it, he simply use OBS to layer a web service on top of his webcam and screen. Technically, it uses WebSockets and some tricks to layer its web service onto its screen.
As usual, we followed MTS with a (Zoom-ised) beer bash!
