gzip_proxied question

[bryndole]

I'm new to nginx. After setting up a reverse proxy and reading the documentation I am still left baffled over what the gzip_proxied option does.

http://wiki.nginx.org/NginxHttpGzipModule#gzip_proxied

gzip_proxied

syntax: gzip_proxied  ...

default: gzip_proxied off

context: http, server, location

It allows or disallows the compression of the response for the proxy request in the dependence on the request and the response. The fact that, request proxy, is determined on the basis of line "Via" in the headers of request. In the directive it is possible to indicate simultaneously several parameters: 


I'm guessing the description is directly translated from the Russian? Google translate offers the following:


Enables or disables compression using gzip to answer proxied requests depending on the request and response. The fact that, proxied request is determined on the basis of the line "Via" in the request header. The directive can specify multiple paarmetrov:


Not sure what the "Via" request header is. 

Can someone explain (in English please!) what this option does? My hunch (hope) is that it may enable pass through for gzip'd responses from the backend? Am I close?

Thanks in advance,

Bryn

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,60121,60121#msg-60121