if-range requests and compressed response

Hi All,

Can someone clarify on which representation the "Range" points to for an
"If-Range" request, when the original response was compressed.

 * Should the server return the specified range from the compressed
response (i.e. compress the original content again, if needed, and send the
relevant range, assuming the compression algorithm generates the same byte
stream again as the previous response!!) or
 * does the range point to bytes from the (decompressed/)uncompressed
response? if so, can the 206 partial response be non-compressed, though the
original response was compressed. How will client "fill" its cache with this
range? (i.e. will the client cache have a complete response after receiving
this for the given E-Tag?)

Also, If the Range points into compressed response, then I need a second
clarification, when if-range has an E-tag and when it carries a date.When
the If-Range carries an E-tag, we know if the original response was
compressed or not. But with last modified date, how to determine if the
original response was compressed or not?


Thanks in advance,
Ashok