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I’m diving into the link layer of the Internet Protocol Suite in Go, where I'll show you how to read and craft IP headers, particularly for sending and receiving ICMP ping packets. I begin by creating a raw socket with `syscall.Socket`, using `AF_INET` for IPv4, `SOCK_RAW` to handle raw IP packets, and `IPPROTO_ICMP` to filter for ICMP only. I'll demonstrate how to read packets in a loop and then

At the IP layer, you can work with protocols beyond TCP and UDP and craft your own packets. To read the first ICMP packet on localhost in Go, use the `net` package to listen on a raw socket. You'll need root privileges to do this. When you run the program, you can ping localhost and observe the raw bytes of ICMP packets. If you switch to TCP, you’ll see the packet headers instead. To send a TCP pa

Facebook faces significant software quality issues, as illustrated by three key exhibits. First, the iOS app’s complexity, with over 18,000 Objective-C classes and contributions from 429 developers, indicates a lack of architectural coherence that hinders efficient feature addition. Second, a Facebook research paper reveals that data loading inefficiencies stem from format conversion, despite sugg

To run a real-time project efficiently, using Socket.io on Node.js and Django on Nginx/Gunicorn on the same port with SSL, follow these steps on Ubuntu: Start by generating a self-signed SSL certificate. Use Stunnel to decrypt SSL traffic, supporting both HTTPS to HTTP and WSS (WebSocket Secure) to WS. Employ HAProxy to route WebSocket traffic to Node.js and web traffic to Nginx since Nginx doesn'

During my paternity leave, I built an in-memory hashmap in Go, Python, and C to explore implementing an alternative to memcached and to challenge my programming skills across these languages. Each version supports the essential `get` and `set` commands from the memcached protocol, allowing it to work with a memcached client. The code is available on GitHub as Key-Value-Polyglot, and I've actively

Credit card numbers that conform to the Luhn formula (MOD 10 check). Usefull for testing e-commerce sites (because they should get past any pre-validation you do, and be declined at the card processor or bank stage). In testing situations any expiry date within the next 3 years should work Feedback forces me to clarify this: These are NOT valid credit card numbers. You can’t buy anything with thes