A Cisco API provides Last-Modified on a GET response but no ETag. How should the consumer optimize the next GET?
Select an answer to reveal the explanation.
Short Explanation
No ticket stub? Use the date stamp on the package instead. Last-Modified plus If-Modified-Since is the date-based twin of ETag validation—same family of savings, no vendor extension required.
Full Explanation
When an API offers Last-Modified, the consumer’s subsequent GET should carry If-Modified-Since with that timestamp. The server can then omit an unchanged body, just as with ETag validators. Date-based and ETag-based conditional GETs are both valid HTTP cache optimizations; neither requires a proprietary cache product.