Reading the source is an important part of open source software. It means users have the ability to look at the code and see what it does.
But "read the source" doesn't apply only to code. Understanding the standards the code implements can be just as important. These standards are codified in documents called "Requests for Comments" (RFCs) published by the Internet Engineering Task Force[1] (IETF). Thousands of RFCs have been published over the years, so we collected a few that our contributors consider must-reads.
6 must-read RFCs
RFC 2119—Key words for use in RFCs to indicate requirement levels
This is a quick read, but it's important to understanding other RFCs. RFC 2119[2] defines the requirement levels used in subsequent RFCs. What does "MAY" really mean? If the standard says "SHOULD," do you really have to do it? By giving the requirements a well-defined taxonomy, RFC 2119 helps avoid ambiguity.
RFC 3339—Date and time on the internet: timestamps
Time is the bane of programmers the world over. RFC 3339[3] defines how timestamps are to be formatted. Based on the ISO 8601[4] standard, 3339 gives us a common way to represent time and its relentless march. For example, redundant information like the day of the week should not be included in a stored timestamp since it is easy to compute.
RFC 1918—Address allocation for private internets
There's the internet that's everyone's and then there's the internet that's just yours. Private networks are used all the time, and RFC 1918[5] defines those networks. Sure, you could set up your router to route public spaces internally, but that's