RFC-154
by Darius Kazemi, June 3 2019
In 2019 I'm reading one RFC a day in chronological order starting from the very first one. More on this project here. There is a table of contents for all my RFC posts.
Defensive pedantry
RFC-154 is titled “Exposition Style”. It's by Steve Crocker and dated May 12th, 1971.
The technical content
So. This one-page RFC seems completely off-topic, until you look at the metadata in the upper left corner of the page:
Updates: #107
Obsoletes: #132
If we look at RFC-132, we see that it's correcting an error in Crocker's RFC-107. This RFC is correcting an error (or misunderstanding) in that correction. The exact passage from RFC-107 in contention here is:
Each of these numbers is interpreted as "the number of 128ths of the current allocation" to be returned if it is in the range of 0 to 128, and is to be interpreted as "all of the current allocation", if it is in the range 128 to 255.
In RFC-132, Jim White says that the “0 to 128
” should actually read “0 to 127
”. Crocker in this RFC is claiming that he was correct the whole time. His argument is: if I'm describing two ranges of values, those ranges can overlap on their boundary as long as both claims about both ranges are true for the value on the boundary. In other words:
- because 128/128 = 1 aka 100% allocation
- and because the range 128 to 255 is meant to describe 100% allocation
- he is not technically wrong to specify the 0 to 128 range; all values are correctly described
Analysis
Look. Crocker is correct that he's not wrong. But Jim White is correct in that that double-specifying the value of 128, when either range correctly specifies it, is just plain confusing.
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About me
I'm Darius Kazemi. I'm an independent technologist and artist. I do a lot of work on the decentralized web with ActivityPub, including a Node.js reference implementation, an RSS-to-ActivityPub converter, and a fork of Mastodon, called Hometown. You can support my work via my Patreon.