- From: Balint Nagy Endre <bne@bne.ind.eunet.hu>
- Date: Wed, 28 Feb 1996 01:54:57 +0100 (MET)
- To: hallam@w3.org
- Cc: bne@bne.ind.eunet.hu, http-caching@pa.dec.com
Phill Hallam writes [in reply to me]: > > Could you expand upon the problem of dial up users on the end of > a phone line? Service providers usually don't offer call-out services on phone lines, consequently the client side proxy can be contacted only when the client triggers the dial-out process. (X.25 has a 'reverse charge option' on calls, for X.25 links this isn't a problem. I guess ISDN has a similar feature.) At least the NOTIFYs should be queued up at the internet side until the proxy 'calls out'. > I did have a number of thoughts about this case, in particular about > clients doing aggressive pre-fetch. If I go to the index of the > new york times it should start pusshing the front pages down the line at me so > thsat the minute I finish one page I can read the next. this means that > there should be a mechanism for distinguishing real hits from false > positives. Essential problem! We should address it! > I thought I would try a simple proposal as a start then see which extra features > people thought essential. > > > Perhaps we should regard a proxy cache as being logically a part of the client > in the dialup case. Maybe we should work on a protocol which allows fast co > exchange of data with a proxy on the other side of the line. This would be > the "permanent" representative of the proxy. This server would also be > responsible for handling notification operations as well. Important point. In near future this should be the tipical configuration, turning the problem into a proxy-to-proxy question. (Currently I don't have an outer proxy - and I forgot about my (not too attractive) experience with cascaded CERN proxies in the past.) Having the outer proxy the problem is significantly easier: the outer proxy should batch NOTIFYs until the remote proxy forwards a request. > This is starting to sound like an interesting project, is it really linked to > the log exchange problem or is it something separate however? Taking the proxy-to-proxy configuration into account, the problem seems to me an implementation question with one exception: We need a directive telling "I'm a dialup-IP host". Isn't too ugly to say Proxy-Feature: dialup? This may solve both questions. Andrew. (Endre Balint Nagy) <bne@bne.ind.eunet.hu>
Received on Wednesday, 28 February 1996 01:17:23 UTC