(Weak) ETags and Last-Modified
- by Kai Moritz
As far as I understand the specs, the ETag, which was introduced in RFC 2616 (HTTP/1.1) is a predecessor of the Last-Modified-Header, which is proposet to give the software-architect more controll over the cache-revalidating process.
If both Cache-Validation-Headers (If-None-Match and If-Modified-Since) are present, according to RFC 2616, the…