Is anyone actually USING IP QoS?

Alex P. Rudnev alex at Relcom.EU.net
Tue Jun 15 15:20:43 UTC 1999


> Aleksei,
> I agree that you can solve one-to-many type of applications by smart
> caching. Though the problem now is how much you want to spend on
> caching, where you cache and would it scale well.
I have meant _replication on the fly == multicasting_.

You can build NEW MULTICAST network over the internet, and begin 
multicasting just from the data source. This means _new router features_ 
(buggy and odd for now), new routing protocols (such as PIM, buggy and 
odd), etc etc - a few years (and may be the horse will die BEFORE you'll 
have success). 

Or you can try from the other end - doing replication on the fly, and 
convert existing UNICAST data streams to the multicast if (and where) 
it's nessesary only. Just as WWW caching, you'll have results from the 
first week, and you can do ot one the customer's eddge, on the 
data-source eddge.

I am not shure if the first approach is worst or not, nut for a few 
years there is attempts to build multicast network over the whole 
internet - and it have not eny success except a few of pylot projects. 
Compare RealVideo auditory and multicast auditory for now... And why 
don't try anpther approach.

Alex.
 


> And I'd like to point that multicast tries to solve not only one-to-many
> problem (eg. streaming video) but other scenarios as well. What might be
> alternative for many-to-many apps? How to scale such applications?
> As regarding QoS, I don't think that we'll see a protocol that will
> cover Internet as a whole. In my mind protocol driven QoS is intra-AS or
> intra-ISP issue and crossing AS boundaries is regulated by SLA which is
> hardly dynamic thing ;). Though some statically defined QoS filters
> might be installed. QoS wouldn't create more bandwith but rather make
> billing easier. That's my take on this.
> 
> 	Regards,
> 		Grigorij
> 
> > -----Original Message-----
> > From:	Alex P. Rudnev [SMTP:alex at Relcom.EU.net]
> > Sent:	Tuesday, June 15, 1999 5:44 AM
> > To:	O'Flaherty, Douglas
> > Cc:	nanog at merit.edu; 'steriley at microsoft.com'
> > Subject:	RE: Is anyone actually USING IP QoS?
> > 
> > 
> > // Sorry, if it's not for nanog forum, I can drop it's address from
> > this 
> > // discussion.
> > 
> > > Alex, steve:
> > > 
> > > I know this thread is effectively dead, but I'm just catching up and
> > enjoyed
> > > the discussion very much. It's NANOG so it isn't surprising there
> > was little
> > > discussion of the edge of the networks.
> > > 
> > > No one mentioned critical other functions for multicast and QoS:
> > data
> > > distribution and interactive services. The growth in broadband is
> > putting
> > > new services (and telephone is the simpliest) on the edge of the
> > network.
> > > Data distribution is a model starburst is working on. I think the
> > demand for
> > > it will grow exponentially. 
> > > 
> > > As the broadband world grows there are real oportunities for
> > interactive
> > > content placed near the edge of the network. This can not be
> > centrally
> > > placed because of latency requirements for interactivity. The
> > architecture
> > > requires 1000s of servers with pratically identical data on them.
> > It's much
> > > like a proxy pre-fetching data. The problems is there is lots of it
> > > (100-500G). Multi-cast on public or private net is the logical way
> > to do get
> > > the data there.
> > You areright about multimedia, but I am not sure about multicast. 
> > Russions are saying - if you see the banner _elebhant_ on the cell
> > with 
> > the monkey in the zoo - don't believe to trhe banner.
> > 
> > Just there. Multicasting is the beautiful idea, nice banner. But look
> > on 
> > the real world. There is MULTIMEDIA ALREADY - I can get CNN TV, I can
> > get 
> > different music, I can look on the shattle lanch in real time -
> > withouth 
> > multicasting. There is already EXISTING MULTIMEDIA in the network - 
> > RealVideo and StreamVideo/on/demand.
> > 
> > Not I have a question. No doubt, if 1000 customers ask RV stream from
> > the 
> > CNN, the network fail down (or exactly server refuse to do it). This
> > mean 
> > _this data have to be REPLICATED on the FLY_. 
> > 
> > There is a few different ways to do such replication. One way is 
> > MULTICASTING. It was developed for the LAN networks (because there is
> > not 
> > other way to replicate data over the ethernet) and it's the only way
> > to 
> > get multicast in the LAN if you need strong replication. But in real 
> > life, LAN network are not bottlechecks for this multimedia - if all 
> > RELCOM's employees ask RV CNN at once, our LAN networks can hold this 
> > traffic withouth big problems (128Kbit * 100 = 12,8Mbit - less than 1 
> > 100BaseTX ethernet!). 
> > 
> > The other way is CACHING. Caching on the fly or caching with the short
> > 
> > time to live.
> > 
> > There is two differences between this ways. Multicasting need another 
> > routing scheme, another address scheme, it's really ONE ANOTHER
> > network. 
> > Caching need... no changes for the customer, just catch request on the
> > 
> > fly (as WWW CACHE ENGINE by CISCO do for the WWW requests) and CACHE
> > data 
> > on the fly). 
> > 
> > Now compare. One scheme need one another set of aggreements, one
> > another 
> > set of configurations, etc etc... It's the only way for the DENSE 
> > MULTIMEDIA (if you need TV for the 1000 customers at one LAN at once,
> > for 
> > example). Another way need one more protocol (such as
> > WWW-CACHE-CONTROL 
> > protocol by CISCO, sorry I don't remember RFC number for it) but for
> > some 
> > MultiMedia requests (RealVideo and StreamVideo are enougph for now),
> > no 
> > aggreements, no additional configurations schemas, no changes for the 
> > customers and/or service providers. Guess what's better.
> > 
> > And in real live, we have not multicast in the Internet. We have some 
> > SHOWS, but use RVplayer or other _request and send_ systems filled up
> > by 
> > the information and music. And if someone propose effective cache
> > engine 
> > for this streams - he'll be winner, not multicasting.
> > 
> > Of course, no one prevent this cache engine from doing multicasting 
> > locally.
> > 
> > What's about QoS - first, you need something simple oer the whole 
> > Internet. Then you can speak about RSVP and so on - if don't WDM kill
> > it 
> > for this future time.
> > 
> > Alex.
> > -----
> > 
> > 
> > > As these new services are offered the need for QoS in the last mile
> > will be
> > > more critical. Some of these apps require minimal latency or strict
> > packet
> > > order. There is a strong future for QoS, but edge networks will
> > require it
> > > much more than the Internet.
> > > 
> > > I work for one of the new interactive companies. The lack of good
> > tools and
> > > protocols is keeping me up at night.
> > > 
> > > doug
> > > 
> > > douglas o'flaherty
> > > dir ops & support
> > > arepa.com
> > > 
> > > 
> > > 
> > > -----Original Message-----
> > > From: Alex P. Rudnev [mailto:alex at Relcom.EU.net]
> > > Sent: Tuesday, May 18, 1999 5:17 AM
> > > To: Steve Riley (MCS)
> > > Cc: nanog at merit.edu
> > > Subject: RE: Is anyone actually USING IP QoS?
> > > 
> > > 
> > > 
> > > I must agree and disagree. RSVP is dead protocol - it's enougph to 
> > > imagine how different ISP can negotoate about RSVP service, and (in 
> > > addition) read RSVP protocol itself...
> > > 
> > > On the other hand, why don't provide QoS in the non-overbooked
> > network. 
> > > It's not difficult to install PRECEDENCE queue-control, just as
> > negotiate 
> > > about some classes of service, to prevent short network bursts from 
> > > disturbing multimedia streams.
> > > 
> > > I'd like to ask one more question. Multicast, 
> > > 
> > > If we project multimedia services from the scratsch, you have a few 
> > > different choices. For example, you have RealVideo server. I ask you
> > 
> > > abgour RV stream. Ok, you send packets with DST=MY_ADDRESS.
> > > 
> > > Then someone else send second request. Why (WHY) can't RV server add
> > 
> > > second DST address into the packet? Why can't you use the same,
> > unicast, 
> > > address space for multicast services.
> > > 
> > > I mean - first way was (was) to use existing address space for
> > multicast 
> > > multimedia, and add some mechanism (such as replicators) to hide the
> > 
> > > mechanisms from the end user. No one bother if some RV-CACHE server
> > catch 
> > > his request and use his own replicator to organise multidemia
> > stream.
> > > 
> > > Second way was choosen - to use another address space for the
> > multimedia 
> > > multicasting. Result - you see - Internet have not (HAVE NOT)
> > multimedia 
> > > multicast at all. No, some ISP have internal multicast networks, but
> > not 
> > > more. If I ask CNN abour RV live stream, and you ask the same, be
> > sure - 
> > > the server send just 2 different packets - one for you and one for
> > me...
> > > 
> > > And this is very serious obstacle against multimedia services in the
> > 
> > > Internet. Not QoS (through QoS prevent using existing public
> > networks 
> > > from the commercial telephony), but tjis absence of mukticasting in
> > the 
> > > Internet.
> > > 
> > > 
> > > 
> > > On Mon, 17 May 1999, Steve Riley (MCS) wrote:
> > > 
> > > > Date: Mon, 17 May 1999 14:04:37 -0700
> > > > From: Steve Riley (MCS) <steriley at microsoft.com>
> > > > To: nanog at merit.edu
> > > > Subject: RE: Is anyone actually USING IP QoS?
> > > > 
> > > > 
> > > > Nice to see that I'm not the only one believing in the foolishness
> > of QoS
> > > > hype. Bandwidth is essentially free, and will always be cheaper
> > than QoS.
> > > > And since in the end nearly all decisions are based on economics,
> > it
> > > should
> > > > be apparent which is the more logical decision.
> > > > 
> > > > Allow me to point you to an interesting paper called "Rise of the
> > Stupid
> > > > Network." Many of you here may have already seen this. It was
> > written back
> > > > in 1997 by David Isenberg, then a reasearcher at AT&T Labs
> > (Isenberg is
> > > now
> > > > an independent consultant). His paper profoundly changed my views
> > on QoS
> > > and
> > > > made me realize that networks perform best when we limit how smart
> > they
> > > get
> > > > and ensure that networks focus on transport only. I urge everyone
> > to read
> > > > it.
> > > > 
> > > > Paper: http://www.rageboy.com/stupidnet.html
> > > > Isenberg's site: http://www.isen.com/
> > > > 
> > > > _________________________________________________________
> > > > Steve Riley
> > > > Microsoft Telecommunications Practice in Denver, Colorado
> > > >     email: mailto:steriley at microsoft.com
> > > >     call: +1 303 521-4129 (cellular)
> > > >     page: +1 888 440-6249 or mailto:4406249 at skytel.com
> > > > Applying computer technology is simply finding the right wrench to
> > pound
> > > in
> > > > the correct screw.
> > > > 
> > > > 
> > > > 
> > > > -----Original Message-----
> > > > From: Vadim Antonov [mailto:avg at kotovnik.com]
> > > > Sent: Monday, May 17, 1999 12:28 PM
> > > > To: nanog at merit.edu; pete at kruckenberg.com
> > > > Subject: Re: Is anyone actually USING IP QoS?
> > > > 
> > > > 
> > > > Yep.  Altough not _all_ QoS schemes are broken-as-designed.  The
> > > > most trivial per-packet priority combined with ingress
> > > > priority mix shaping works.  Ths idea of end-to-end
> > > > whatever reservations or guarantees is usually propounded
> > > > by people who either neglected their CS courses or those
> > > > who are trying to sell it.
> > > > 
> > > > Yep.  The biggest QoS secret is that nobody actually needs
> > > > it.  Bandwidth is cheap and is growing cheaper.  The
> > > > manpower needed to deploy and maintain QoS is getting
> > > > more and more expensive.
> > > > 
> > > > --vadim
> > > > 
> > > > 
> > > 
> > > Aleksei Roudnev, Network Operations Center, Relcom, Moscow
> > > (+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095)
> > 230-41-41,
> > > N 13729 (pager)
> > > (+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)
> > > 
> > > 
> > 
> > Aleksei Roudnev, Network Operations Center, Relcom, Moscow
> > (+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095)
> > 230-41-41, N 13729 (pager)
> > (+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)
> > 
> 

Aleksei Roudnev, Network Operations Center, Relcom, Moscow
(+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41, N 13729 (pager)
(+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)





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