The Backend Engineering Show with Hussein Nasser

In this video I discuss my approach of learning new technology and how I break it down so I understand it. Hope it helps

The InterPlanetary File System (IPFS) is a protocol and peer-to-peer network for storing and sharing data in a distributed file system. IPFS uses content-addressing to uniquely identify each file in a global namespace connecting all computing devices. Intro 0:00 Why IPFS? 2:00 Explain the original web model and the limitation * Content addressing instead of location addressing * decentralized content distributed among peers Content 3:30 * Content is hashed as CID * Content is immutable each update generates new CID * Content addressing Routing 4:30 * Distributed Hash Table (DHTs) maps CID / Peer IP address * DHT server hosts content and DHT Publishing Content 6:30 * New Content that you want to share on ipfs * hash the content creating new CID * Update your local DHT CID / your ip address * DHT will be updated to all the content peer (NOT the CONTENT) * People searching for your CID will be connected to you and only you. Consuming Content 8:48 * ipfs client (dht client) want to consume Ipfs://cid/ * ipfs client consults its local DHT table to see where this CID is located, gets back a collection of IP addresses * client connects to some or all the peers found hosting that CID * client downloads chunks of the content from each peer so it speeds up * Once the client has the content it is now also updating its local DHT table that it now also hosts that CID (if it supports being a DHT server) * New updated DHT is propogated across peer IPFS Overview (Digrams) 11:30 Demo 13:45 More Information 18:30 Immutable Content * if Content gets updated changes URI how do I inform the user? * hash the public key of the user instead and share that Brand new Client/server * I know nothing about the network (Bootstraping) * you will be bootstrapped with a collection of ip addresses to start you up. More * IPFS gateway * IP Name server * Solve content * Deleting Content( once other node hosts it no way to delete it from their network) NAT traversal Resources https://datatracker.ietf.org/meeting/interim-2020-dinrg-01/materials/slides-interim-2020-dinrg-01-sessa-an-overview-of-the-interplanetary-file-system-ipfs.pdf https://www.youtube.com/watch?v=K4Usud4g4iY&feature=youtu.be&t=1008 https://twitter.com/hnasr/status/1353548949945163776?s=21 https://docs.ipfs.io/conce 🎙️Listen to the Backend Engineering Podcast https://husseinnasser.com/podcast 🏭 Backend Engineering Videos https://backend.husseinnasser.com 💾 Database Engineering Videos https://www.youtube.com/playlist?list=PLQnljOFTspQXjD0HOzN7P2tgzu7scWpl2 🏰 Load Balancing and Proxies Videos https://www.youtube.com/playlist?list=PLQnljOFTspQVMeBmWI2AhxULWEeo7AaMC 🏛️ Software Archtiecture Videos https://www.youtube.com/playlist?list=PLQnljOFTspQXNP6mQchJVP3S-3oKGEuw9 📩 Messaging Systems https://www.youtube.com/playlist?list=PLQnljOFTspQVcumYRWE2w9kVxxIXy_AMo Become a Member https://www.youtube.com/channel/UC_ML5xP23TOWKUcc-oAE_Eg/join Support me on PayPal https://bit.ly/33ENps4 Join our Thriving Backend Community on Discord https://discord.com/invite/CsFbFce Stay Awesome, Hussein

It looks like digital certificates and other certificate authorities issued by Spanish certificate authority Camerfirma will stop working in Chrome 90, in April.   https://www.zdnet.com/article/google-bans-another-misbehaving-ca-from-chrome/  https://wiki.mozilla.org/CA:Camerfirma_Issues

I explain why and when SELECT * can become expensive. 

David Schuts, a security researcher earned $5000 dollars in Google VRP by finding a Backend YouTube API that leaks Private Video Thumbnails. let us discuss how did he do that.   Resources https://bugs.xdavidhu.me/google/2021/01/11/stealing-your-private-videos-one-frame-at-a-time/ Twitter @xdavidhu https://twitter.com/xdavidhu

A vulnerability in Google Feedback component in postMessage allowed this security researcher to find a way to hijack private screenshots   https://blog.geekycat.in/google-vrp-hijacking-your-screenshots/ https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage

Brave supports IPFS (InterPlanetary File System) which is a protocol designed to replaced HTTP as a decentralized alternative. This allows users to host and consume   Resources https://brave.com/brave-integrates-ipfs/ https://ipfs.io/#how

The current FTP implementation in Google Chrome has no support for encrypted connections (FTPS), nor proxies. Usage of FTP in the browser is sufficiently low that it is no longer viable to invest in improving the existing FTP client. In addition more capable FTP clients are available on all affected platforms.  Google Chrome 72+ removed support for fetching document subresources over FTP and rendering of top level FTP resources. Currently navigating to FTP URLs result in showing a directory listing or a download depending on the type of resource. A bug in Google Chrome 74+ resulted in dropping support for accessing FTP URLs over HTTP proxies. Proxy support for FTP was removed entirely in Google Chrome 76.  Remaining capabilities of Google Chrome’s FTP implementation are restricted to either displaying a directory listing or downloading a resource over unencrypted connections. We would like to deprecate and remove this remaining functionality rather than maintain an insecure FTP implementation. Resources https://bugs.chromium.org/p/chromium/issues/detail?id=333943 https://docs.google.com/document/d/1JUra5HnsbR_xmtQctkb2iVxRPuhPWhMB5M_zpbuGxTY/edit# https://www.chromestatus.com/feature/6246151319715840

On Jan 4th 2021, Slack experienced a global outage that prevented customers from using the service for nearly 5 hours. Slack has released the Root cause analysis incident report which I’m going to summarize in the first part of this video. After that Ill provide a lengthy deep dive of the incident so make sure to stick around for that. If you are new here, I make backend engineering videos and also cover software news, so make sure to Like comment and subscribe if you would like to see more plus it really helps the channel, lets jump into it. So This is an approximation of Slack’s architecture based on what was the described in the reports. Clients connects to load balancers, load balancers distribute requests to backend servers and backend servers finally make requests to database servers which is powered by mysql through vitess sharding. All of those are connected by routers in cross boundary network. Around 6AM jan 4 , the cross network boundary routers setting between LB and backend and backend to DB started to drop packets. This lead to the load balancers slowly marking backends as unhealthy and removing them from the fleet Which compounded the amount of requests The number of failed requests eventually triggered the provisioning service to start spinning an absurdly large number of backend servers However the provisioning service couldn’t keep up with the huge demand and shortly started to time out for the same networking reasons and eventually ran out of maximum open file handles. Eventually Slack’s cloud provider increased the networking capacity and backend servers went back to normal around 11 AM PST This was a summary of the slack outage, Now set back, grab your favorite beverage and lets go through the detailed incident report! 0:00 Outage Summary 2:00 Detailed Analysis Starts 5:20 The Root Cause 30:00 Corrective Actions

In this video I go through the new most exciting features in HAProxy, one of my favorite proxies. HAProxy 2.3 adds exciting features such as forwarding, prioritizing, and translating of messages sent over the Syslog Protocol on both UDP and TCP, and OpenTracing SPOA, Stats Contexts, SSL/TLS enhancements, an improved cache, and changes in the connection layer that lay the foundation for support for HTTP/3 / QUIC. Resources https://www.haproxy.com/blog/announcing-haproxy-2-3/ 0:00 Intro 2:00 Connection Improvements 5:40 Load Balancing 11:36 Cache 15:00 TLS Enhancements