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http-headershttp2huffman-codehpack

Is the famous HPACK demo diagram wrong?

enter image description here

I was so much confused by 19 in the rightmost picture, which IMHO would be 4 [2].

The slide is from https://docs.google.com/presentation/d/1r7QXGYOLCh4fcUq0jDdDwKJWNqWK1o4xMtYpKZCJYjM/edit#slide=id.gfd0e3427_048

[2] https://http2.github.io/http2-spec/compression.html#rfc.section.A

Solution

  • Yes looks wrong to me too, and I agree it should be 4 for :path and not 19 for accept.

    The presenter's book High Performance Browser Networking (available online for free) has this in the HPACK section:

    HPACK header compression example

    Which, as you can see, did include the accept header so suspect they just made a typo when they simplified the example for the slides.