TCP Puzzlers | Triton DataCenter
It's been said that we don't really understand a system until we understand how it fails. Despite having written a (toy) TCP implementation in college and then working for several years in industry, I'm continuing to learn more deeply how TCP works — and how it fails. What's been most surprising is how basic some of these failures are. They're not at all obscure. I'm presenting them here as puzzle
Google’s QUIC protocol: moving the web from TCP to UDP
Want to help support this blog? Try out Oh Dear, the best all-in-one monitoring tool for your entire website, co-founded by me (the guy that wrote this blogpost). Start with a 10-day trial, no strings attached. We offer uptime monitoring, SSL checks, broken links checking, performance & cronjob monitoring, branded status pages & so much more. Try us out today! The QUIC protocol (Quick UDP Internet
Why we use the Linux kernel's TCP stack
A recent blog post posed the question Why do we use the Linux kernel's TCP stack?. It triggered a very interesting discussion on Hacker News. I've also thought about this question while working at CloudFlare. My experience mostly comes from working with thousands of production machines here and I can try to answer the question from that perspective. CC BY 2.0 image by John Vetterli Let's start wit
Coping with the TCP TIME-WAIT state on busy Linux servers | Vincent Bernat
TL;DR Do not enable net.ipv4.tcp_tw_recycle—it doesn’t even exist anymore since Linux 4.12. Most of the time, TIME-WAIT sockets are harmless. Otherwise, jump to the summary for the recommended solutions. The Linux kernel documentation is not very helpful about what net.ipv4.tcp_tw_recycle and net.ipv4.tcp_tw_reuse do. This lack of documentation opens the path to numerous tuning guides advising to
Improving TCP performance over a gigabit network with lots of connections and high traffic of small packets
I’m trying to improve my TCP throughput over a “gigabit network with lots of connections and high traffic of small packets”. My server OS is Ubuntu 11.10 Server 64bit. There are about 50.000 (and growing) clients connected to my server through TCP Sockets (all on the same port). 95% of of my packets have size of 1-150 bytes (TCP header and payload). The rest 5% vary from 150 up to 4096+ bytes. Wit
Let's code a TCP/IP stack, 1: Ethernet & ARP
Writing your own TCP/IP stack may seem like a daunting task. Indeed, TCP has accumulated many specifications over its lifetime of more than thirty years. The core specification, however, is seemingly compact1 - the important parts being TCP header parsing, the state machine, congestion control and retransmission timeout computation. The most common layer 2 and layer 3 protocols, Ethernet and IP re
Why you should understand (a little) about TCP
November 21, 2015 This isn’t about understanding everything about TCP or reading through TCP/IP Illustrated. It’s about how a little bit of TCP knowledge is essential. Here’s why. When I was at the Recurse Center, I wrote a TCP stack in Python (and wrote about what happens if you write a TCP stack in Python). This was a fun learning experience, and I thought that was all. A year later, at work, so
TCP Fast Open – Webを速くするためにGoogleがやっていること Make the Web Faster 4 –
TCP Fast Open – Webを速くするためにGoogleがやっていること Make the Web Faster 4 – Jxck HTTPは、その下層にあたるトランスポートレイヤーのプロトコルとして、通常TCPを使用します。 したがって、TCPのレイヤで速度が改善することは、そのままWebの高速化につながる可能性があるといえます。 GoogleはWebを速くするための活動として、TCPのようなプロトコルレイヤの改善にも取り組んでいます。 今回はその中の一つ、TCP Fast Openを取り上げ、解説と動作検証、簡単なベンチマークを行います。 検証環境等は最下部に記載します. Make the Web Faster: TCP Fast Open 3 Way Handshake TCPは、「正確、確実にデータを届ける」ことを重視した設計になっています。 特に接続確立時には、双方の状
netstatコマンドを使いこなす ＠IT：Windows TIPS -- Tips：
TCP/IP関連のトラブルシューティングを行う場合に、必ずといってよいほど使うコマンドとして「netstat」コマンドがある（実行ファイル名はnetstat.exe）。このコマンドは、主にTCPの通信状態を調べるためには必須であり、ぜひともその使い方をマスターしておきたい。 netstatの基本――通信中のTCPコネクションの調査 netstatコマンドの最も基本的な使い方は、通信中のTCPコネクション（TCP接続）の状態を表示させることである。このコマンドを実行すると、ローカルPCのTCP/IPプロトコルスタック上において、現在アクティブになっているTCP通信の状態を表示できる。 ●「TCP」とは？ 「コネクション」とは？ TCPとは、2つのアプリケーション間で、信頼性のある通信路（コネクション）を開設し、お互いにデータなどをやりとりするための機能である。通信するアプリケーションは、同一
1
リリース、障害情報などのサービスのお知らせ
最新の人気エントリーの配信
j次のブックマーク
k前のブックマーク
lあとで読む
eコメント一覧を開く
oページを開く
TIME_WAIT and its design implications for protocols and scalable client server systems - ServerFramework.com