Bloom filter is indeed a sufficiently obvious idea that it got already proposed. But it wasn't accepted and was expired in 2019. See Cache Digests for HTTP/2.

Bloom filter is indeed a sufficiently obvious idea that it got already proposed. But it wasn't accepted and was expired in 2019. See Cache Digests for HTTP/2. https://tools.ietf.org/html/draft-ietf-httpbis-cache-digest-05 https://tools.ietf.org/html/draft-ietf-httpbis-cache-digest-...