nanog mailing list archives
RE: Is anyone actually USING IP QoS?
From: Jamie Scheinblum <jamie () fast net>
Date: Tue, 15 Jun 1999 17:14:51 -0400
While this thread is slowly drifting, I disagree with your assertion that so much of the web traffic is cacheable (nlanr's caching effort, if I remember, only got around 60% of requests hit in the cache, pooled over a large number of clients. That probably should be the correct percentage of cacheable content on the net). If anything, the net is moving to be *more* dynamic. The problem is that web sites are putting unrealistic expires on images and html files because they're being driven by ad revenues. I doubt that any of the US based commercial websites are interested in losing the entries in their hit logs. Caching is the type of thing is totally broken by session-ids, (sites like amazon.com and cdnow). The only way caching is going to truly be viable in the next 5 years is either by a commercial company stepping in and working with commercial content providers (which is happening now), or webserver software vendors work with content companies on truly embracing a hit reporting protocol. So basically, my assertion is that L4 caching on any protocol will not work if the content provider is given any control of TTL and metrics. The only way web caching *really* works is when people get aggressive and ignore the expire tags from a network administrator point of view, not a content company's. From what I remember, that was the only way the some Australian isps were able to make very aggressive caching work for them. Further, the more you rely on L4 implementations for caching, the more it seems you would be open to broken implementations... Although that is a broad statement... -jamie () networked org
-----Original Message----- From: Vadim Antonov [SMTP:avg () kotovnik com] Sent: Tuesday, June 15, 1999 4:23 PM To: Brett_Watson () enron net; nanog () merit edu Subject: Re: Is anyone actually USING IP QoS? 99% of Web content is write-once. It does not need any fancy management. The remaining 1% can be delivered end-to-end. (BTW, i do consider intelligent cache-synchronization development efforts seriously misguided; there's a much simpler and much more scalable solution to the cache performance problem. If someone wants to invest, i'd like to talk about it :)even if i assume caching is as efficient, or more so, than multicast, i'm still just trading one set of security/scalability concerns for others. caching is no more a silver bullet than multicast.It is not that caching is a silver bullet, it is rather that multicating is unuseable at a large scale.i won't deny the potential scalability problems but i think your generalizing/oversimplifying to say caching just works and has nosecurityor scalability concerns.Well, philosophical note: science is _all_ about generalizing. For an inventor of perpetuum mobile the flat refusal of a modern physicist to look into details to assert that it will not work sure looks as an oversimplifying. After all, the details of actual construction sure are a lot more complex than the second law of thermodynamics. In this case, i just do not care to go into details of implementations. The L2/L3 mcasting is not scalable and _cannot be made_ scalable for reasons having nothing to do with deficiencies of protocols. Caching algorithms do not have similar limitations, solely because they do not rely on distributed computations. So they have a chance of working. Of course, nothing "just works". --vadim PS To those who point that provider ABC already sells mcast service: there's an old saying at NASA that with enough thrust even pigs can fly. However, no reactively propulsed hog is likely to make it to an orbit all on its own.
Current thread:
- Re: Is anyone actually USING IP QoS?, (continued)
- Re: Is anyone actually USING IP QoS? Alex P. Rudnev (Jun 15)
- Re: Is anyone actually USING IP QoS? Brett_Watson (Jun 15)
- Re: Is anyone actually USING IP QoS? Alex P. Rudnev (Jun 15)
- Re: Is anyone actually USING IP QoS? Danny McPherson (Jun 15)
- Re: Is anyone actually USING IP QoS? Barry Dykes (Jun 15)
- Re: Is anyone actually USING IP QoS? Vadim Antonov (Jun 15)
- Re: Is anyone actually USING IP QoS? Vadim Antonov (Jun 15)
- Re: Is anyone actually USING IP QoS? Vijay Gill (Jun 15)
- Re: Is anyone actually USING IP QoS? Danny McPherson (Jun 15)
- Re: Is anyone actually USING IP QoS? Alex P. Rudnev (Jun 16)
- RE: Is anyone actually USING IP QoS? Jamie Scheinblum (Jun 15)
- Re: Is anyone actually USING IP QoS? hardie (Jun 15)
- RE: Is anyone actually USING IP QoS? Alex P. Rudnev (Jun 16)
- Re: Is anyone actually USING IP QoS? Vadim Antonov (Jun 15)
- Re: Is anyone actually USING IP QoS? Vijay Gill (Jun 15)
- Re: Is anyone actually USING IP QoS? smd (Jun 15)
- RE: Is anyone actually USING IP QoS? Vadim Antonov (Jun 15)
- Re: Is anyone actually USING IP QoS? Brett_Watson (Jun 16)
- Re: Is anyone actually USING IP QoS? Vadim Antonov (Jun 16)
- Re: Is anyone actually USING IP QoS? Dorian Kim (Jun 16)
- Re: Is anyone actually USING IP QoS? Alex P. Rudnev (Jun 16)
(Thread continues...)