What does “subrange” mean in the HTTP specification?

Question

See, for example, §13.3.3 and §13.3.4 .

It does not seem to me that this may be related to the “media range” ( §14.1 , for example Accept: text/*), nor the “language range” ( §14.4 , for example Accept-Language: da, en-gb;q=0.8, en;q=0.7).

Maybe this is a “acceptance range” ( §14.5 ) that places byte restrictions on the response? If true, how ETagare related?

Answer 1

I am sure that these are range search queries, i.e. request a portion of the document (for example, resuming file download).

14.35.2 Range Search Requests

HTTP lookup requests using conditional or unconditional GET
methods MAY request one or more sub-ranges of an object, not the entire object, using the range of the request header that applies to the object returned from the request:

If it is ETagweak (starts with W/), then it cannot be used to search for a range - only strong validators can be used for this, or the client may receive an inconsistent file.