On Sun, 14 Jul 2002, Marshall Eubanks wrote:
On Sun, 14 Jul 2002 21:13:13 -0400 (EDT) Art Houle <houle@zeppo.acns.fsu.edu> wrote:
We are using QOS to preferentially drop packets that represent file-sharing (kazaa, gnutella, etc). This saves us 40Mbps of traffic across our multiple congested WAN links. The trick is to mark packets meaningfully. Also, the WFQ introduces some additional latency at our edge.
Is this different from port filtering as is commonly done with, e.g., gnutella ?
Or, to put it another way, how are the packets marked ? And why not just drop them then and there, instead of later ?
If we are not using our WAN connections to capacity, then p2p traffic can expand and fill the pipe, but if business packets are filling the pipes, then the p2p stuff is throttled back. This makes 100% use of an expensive resource.
Regards Marshall Eubanks
On Sun, 14 Jul 2002, Stephen J. Wilcox wrote:
Well, end of the week and the responses dried up pretty quickly, I think
response in itself to my question!
Okay, heres a summary which was requested by a few people:
Other people too are interested in my questions, they dont implement QoS in any saleable manner and wonder how it can be done and whats actually required.
A number of people think QoS was interesting for a while but that its never either found its true use or is dead.
There are unresolved questions from a customer point of view as to what
actually going to get, what difference it will make and how they can measure their performance and the improvements from QoS.
There is a real demand for guaranteed bandwidth, however this tends to be in the form of absolute guarantees rather than improvements above "normal" hence ATM remaining a popular solution.
There is a requirement to differentiate voice traffic, however this is necessarily done by the network anyway in order to offer the service, this being the case the customer doesnt pay extra or gets to know much about how all
fancy bits are done.
On the face of it this is all negative. Nobody has responded saying there are genuine requirements for services to be offered to customers. Nor has anybody responded with any descriptions of implementations.
I conclude either the people doing this are successful and keep their secret safe or the world is yet to sell largescale QoS across IP.
Steve
On Mon, 8 Jul 2002, Stephen J. Wilcox wrote:
Hi all, I've been looking through the various qos/cos options available, my
area was in how IP (MPLS perhaps) compares and can be a substitute for ATM.
Well, theres lots of talk and hype out there, from simple IP queuing eg cisco priority queuing, rsvp, diffserv, mpls traffic engineering etc
But two things are bugging me..
1. To what extent have providers implemented QoS for their customers
2. Hype aside, to what extent do customers actually want this (and by
dont just mean that they want the latest QoS because its the 'latest
thats a they are the particular this I thing',
there has to be a genuine reason for them to want it). And this takes me back to my ATM reference where there is a clear major market still out there of ATM users and what would it take to migrate them to an IP solution?
Also, how are people implementing bandwidth on demand (dynamic allocation controlled by the customer) solutions to customers
Cheers
Steve
Art Houle e-mail: houle@acns.fsu.edu. Academic Computing & Network Services Voice: 850-644-2591 Florida State University FAX: 850-644-8722
Art Houle e-mail: houle@acns.fsu.edu. Academic Computing & Network Services Voice: 850-644-2591 Florida State University FAX: 850-644-8722