My pages are password-protected; how do proxy caches deal with them?
By default, pages protected with HTTP authentication are considered private; they will not be kept by shared caches. However, you can make authenticated pages public with a Cache-Control: public header; HTTP 1.1-compliant caches will then allow them to be cached. If you’d like such pages to be cacheable, but still authenticated for every user, combine the Cache-Control: public and no-cache headers. This tells the cache that it must submit the new client’s authentication information to the origin server before releasing the representation from the cache.