Code change:
Name: zstd-d <del> Description: A stream of bytes compressed using the Zstandard protocol with an external dictionary of not more than 8 MB. </del> <ins> Description: "Dictionary-Compressed Zstandard" data format. </ins> Reference: This document Notes: <del> 4.2. </del> <ins> 6.2. </ins> IANA is asked to update the "Hypertext Transfer Protocol (HTTP) Field Name Registry" registry (HTTP) according to the table below: <del> 5. </del> <ins> 7. </ins> To minimize the risk of middle-boxes incorrectly processing dictionary-compressed responses, compression dictionary transport MUST only be used in secure contexts (HTTPS). <del> 6. </del> <ins> 8. </ins> The security considerations for Brotli RFC7932 and Zstandard RFC8878 apply to the dictionary-based versions of the respective algorithms. <del> 6.1. </del> <ins> 8.1. </ins> The dictionary must be treated with the same security precautions as the content, because a change to the dictionary can result in a

Related discussion:
text: This changes the maximum ZStandard compression window to be the larger of 8 MB and the size of the dictionary. This allows for clients to limit the maximum window size to as low as 8 MB if they like (by not advertising support) while also allowing for clients to use larger dictionaries with ZStandard than they would be able to if the global limit was 8 MB.
NAME and NAME could you also take a look and see if the language looks ok?
Context: URL aims to clarify the window size limit for the Content Encoding token as it wasn't clear in RFC8878. Since the Compression Dictionary Transport draft hasn't been published yet, we should also add some window size considerations to it for and to maintain interoperability. I think in Chrome we ended up using . NAME
NAME could you comment on how this impacts Brotli dictionary decode? Is the dictionary independent from the compression window (so we can adopt the same defaults as or do we need to specify something relative to the size of the dictionary? NAME NAME for ZStandard, to allow for delta-encoding large resources, is reasonable or should it be ? We have use cases for delta-encoding wasm applications where the dictionary can easily be upwards of 50 MB.
For Zstandard, the states that the entirety of the dictionary is accessible as long as the input is <= Window Size. Therefore, to give an extreme case, it's possible to have a 50 MB dictionary, and it's entirely accessible even if the Window Size is only 1 KB, but only as long as the data to de/compress is <= 1 KB. As soon as we reach 1 KB + 1, reaching the dictionary is no longer valid. For delta compression, this has consequences. Presuming the reference is ~50 MB, and the updated content is also ~50 MB, one would need a window size of ~50 MB to ensure access into the dictionary during the entire reconstruction process. But if the updated content is just a bit bigger, say ~51 MB, a ~50 MB window size would allow delta operation only during the first ~50 MB, the last ~1 MB would have to be compressed without dictionary. If follows that the size of the dictionary is irrelevant for the Window size. What matters is for how long one wants to access the dictionary while rebuilding the content.