TFO deployment seems to grow

TCP Fast Open is a TCP extension that enables client and servers to place data inside the SYN and SYN+ACK packets during the three-way handshake. This extension has been pushed by google to speedup short transfers. It is defined in RFC7413 and its Linux implementation is described in a nice article.

Despite being supported by Linux and Apple, it has not yet been widely deployed on servers. Recent measurements collected by show that a growing number of servers support TFO.

TFO is rising

This blog post was written to inform the readers of Computer Networking : Principles, Protocols and Practice about the evolution of the field. You can subscribe to the Atom feed for this blog at These notes are also posted on the ebook’s Facebook page

Written on August 14, 2019