Network

云平台网络的一点思考

Apr 5, 2022 Architecture, Cloud, Network

本文内容受[1]启发 不管云平台的架构如何变化，有一点是始终不变的：虚拟主机通过网卡来发送和接收数据。这些网卡可能是用软件模拟的，或者半虚拟的 ...

TCP 三次握手

Jul 25, 2020 Network, Protocol

TCP建立连接时，实际上时建立两个单向连接来进行双向通信，双方都需要一个发起连接，接收和确认的过程。过程如下： Reference: https://www.guru99.com/tcp-3-way-handshake.html 发起方发送SYN，附带一个 ...

How does flowtrackd detect DDoS in DSR

Mar 16, 2022 Network, DDoS, Security

Cloudflare recently announced flowtrackd which can detect DDoS in [DSR]([[Direct Server Return]]) scenarios. It’s quite interesting since most DDoS protections need the gateway working in the reverse proxy mode, in which the traffic coming and leaving through the same device. Then the gateway can track connection statuses since it observes every packet. I am not an employee of Cloudflare and have no insight of how flowtrackd is designed, but I’d like to have an educated guess. ...