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Pricing and Internet Architecture

Frisky070802 writes "The Politech list recently posted a pointer to a new paper (pdf) by UMN prof Andrew Odlyzko, which compares the telecom industry to the historical transportation industry (railroad, bridges, and such). One quote, from the conclusion, is particularly interesting: '... the networking industry [has] devoted inordinate efforts to technologies such as ATM and QoS, even though there was abundant evidence these were not going to succeed. One can go further and say that essentially all the major networking initiatives of the last decade, such as ATM, QoS, RSVP, multicasting, congestion pricing, active networks, and 3G, have turned out to be duds. Furthermore, they all failed not because the technical solutions that were developed were inadequate, but because they were not what users wanted.'"

10 of 225 comments (clear)

  1. Railroads... by Pig+Hogger · · Score: 5, Interesting
    I have always been interested in railroads, and as I see organizations thriving to work over large areas, I cannot fail to notice that they run in essentially the same problems railroads ran into 150 years ago when they found-out that they had to absolutely synchronize their operations over vast territories in order to simply avoid accidents...

    This is one reason, for example, why Standard Timezones were adopted by the railroads, then telegraphy used to coordinate operations.

    More than 100 years ago, there were elaborate protocols to insure that instructions were transmitted reliably and double-checked to insure that no error of communication occured.

    Of course, the technology used (telegraph keys and, later, telephone) was not as sophisticated as now, but the essential principles (fail-safe, reduntancy checks, retransmission protocols and whatnot) were there.

    It's always fun to watch young pups straight out of school try to solve a problem that was solved more than a century ago by the high-tech industry of the times: the railroads...

    1. Re:Railroads... by Animats · · Score: 5, Interesting
      There are two pre-electronics technologies that anyone designing reliable systems should understand in some detail - railroad signalling and telephone switching. Both were designed to be more reliable than their components. In the relay era, that was essential, because component reliability was mediocre by modern standards.

      The references you need to read are obscure, but exist. For railroad signalling, the technology was mature by 1930. An understanding of either General Railroad Signal or Union Switch and Signal relay-era technology is useful. Both companies produced good books describing their technologies in 1924. There's also "NXSYS", a simulator down to the relay level of New York City subway signalling technology. The key idea to take away from railroad signalling is what "fail-safe" really means and how it is consistently implemented.

      Telephony in the relay era is best understood by studying its most advanced form, Number 5 Crossbar. There are descriptions of the technology in "A Technical History of the Bell System". #5 Crossbar is a transaction-oriented system, in which units of different types do quick transactions to get the job done. Resources of a given type are interchangeable, so losing one unit just reduces call capacity. Resources include originating registers, markers, senders, trunks, translators, billing punches, and trouble recorders. The switch fabric itself is dumb; all the smarts are in the resources. Resources are never tied up for the duration of a call; they're seized from a pool, used for a fraction of a second to a few seconds, and released. That architecture is extremely reliable; no Bell System central office in the relay era was ever down for more than 30 minutes for any reason other than a natural disaster. The key idea to take away from telephony is how interchangeable resources were used to build up a system.

  2. QoS dud? I think not by dmiller · · Score: 5, Insightful

    QoS is far from being a dud - it is a critical part of any VoIP deployment and is now a part of any substantial core network engineering. QoS brokering between ASs (e.g. RSVP) has been a dud so far, but interdomain VoIP is still pretty young so there hasn't been much demand.

    What about architecture changes that have worked? IPsec, ECN, CIDR (and the many changes that came from that, e.g. BGP4) and MPLS? It is too easy to focus on things that failed and ignore the things the silently work.

  3. Wrong... by Gwala · · Score: 5, Insightful

    and say that essentially all the major networking initiatives of the last decade

    Funny, becuase that's the opposite of what I see today. Networking/Telecommunications has never been bigger, and apart from a good portion of the net's underlying protocols, we are constantly surrounded by new networking initiatives that have been blindingly successfull. Since `94, the internet (as far as public use goes) has been a pretty successfull initiative. Let alone a lot of the behind-the-scenes initiatives, like enhancing transoceanic cabling.

    The author of that paper is incredibly vague in his paper -, it's easy to pop off 10 initiatives that failed bigtime (like sattelite phones), but becuase your so used to them, you never notice those that have been successfull (Eg CDMA/GSM, and 3G is popular outside the US). I would go so far as to say that most telecommunication's/network initiatives have been successfull in the last decade, becuase as a planet, we are growing increasingly dependent on communication.

    -Adam

    --
    #!/bin/csh cat $0
  4. Curse of the layered model by G4from128k · · Score: 5, Insightful

    The layered approach to internet infrastructure is a great technological solution for decoupling the physical mechanisms for moving data, the protocols for managing data movements, and the high-level applications that rely on that data. Layers create natural zones of standardization and enable any application to run on any network.

    But that technological architecture is a business model nightmare. All of the costs reside in the lowest physical layers. All those wires, fibers, amplifiers, and switches cost big bucks. Unfortunately, all of the value lies in the highest, application layers. Users want the application and don't care about the physical infrastructure. A layered architecture gaurantees that users don't have to care because the lower layers are interchangable and invisible.

    The result is cut-throat price competition among infrastructure service providers (and the associated miles of dark fiber, negative earnings, high debt, and bankruptcies). Meanwhile, the application providers reap the profits while the infrastructure providers can't justify the expense of solving the last mile problem.

    --
    Two wrongs don't make a right, but three lefts do.
  5. HOWTO: Write a stupid paper by jd · · Score: 5, Informative
    • First, pick a technology that has never been seriously deployed. It greatly helps if none of the readers have any practical, real-world experiences with the subject.
    • Second, always compare with an only marginally related industry or discipline. There has to be enough of a connection to convince the readership, but not enough of one to disprove your preconceived notions.
    • Third, Always tell the audience that they have The Right Thing. It makes them happy. It also makes the usual sponsors of such work (the ones who run the status quo) very happy, too. Happy enough to pay you, for example.

    Seriously, multicaasting is enabled on most of the majopr backbones, but none of the major ISPs supply it - even to broadband customers - at any price. UUnet is one of the few that does. Their links aren't cheap, and from all accounts it can be very hard to get multicasting enabled, simply because a good number of their front-line support people don't know anything about it.

    QoS is likewise serioulsy hindred. Oh, it's used in the field. The transatlantic link between the UK and the US has CBQ (Class Based Queues) enabled to maximise the throughput of important traffic, simply because there's so much.

    Britain's JANET network has a highly extensive network of web caches. The theory being that one of the biggest loads on the transatlantic link is web traffic, and that the same site is often accessed repeatedly (eg: for University coursework), so that the most efficient solution is to cache everything.

    While not strictly "QoS", caching can reduce access times for a web page at peak time from maybe an hour to down to 15 seconds, whilst also massively reducing the load on the network.

    RSVP is a different case. That is known to not scale well over very large, complex multicast networks. (Too much overhead.) However, it is great for local networks, and I'm sure that it will gradually filter its way into Universities and mid-sized corporations, where videoconferencing is useful but bandwidth issues make it impossible to do without some QoS.

    ATM is used by many xDSL companies, as it is a very efficient way to run a fixed-point to a fixed-point. To say it's not used is absurd and shows a degree of ignorance. It's also very popular in Europe, where people perhaps put a little more investment into infrastructure.

    Quick note: I'm a little irritated by hearing some American politician label maglev trains as "sexy science fiction" and "stupid". To me, it's part of a worrying trend I'm seeing in all too much of the US, where there is an apparent phobia of making any actual progress in anything. To me, progress is the certain bit. What happens to those who reject it - that's not so certain.

    How does this fit in? There's only so much bandwidth. Sure, Lucent is up to 3 Terabits per second, but with collapsing R&D funds and Lucent in enough of a financial mess, don't expect either a rollout, or a refinement, any time soon.

    That's the absolute upper cap. The real limit is much smaller. Backbone connections are probably not much more than four or five hundred gigabits per second. (That is to say, about the capacity of two or three hundred well-made Pentium IV-based PCs.)

    A relatively small Beowulf cluster could totally saturate a decent chunk of the Internet backbone. Most cluster-based computers, such as the Origin 3000 or the Altix 3000, with sufficient network links, could easiy max out the capacity of any part of the Internet, without much effort.

    Why isn't the technology used? Because the customer doesn't want it? The customer has never been offered it!! Very, very few customers even know about it!! And ISPs, in particular, are keen to keep it that way. There is much more money to be made from serving people badly, because the customer'll keep paying for improvements and/or support. The ISPs can gouge the more foolish for years

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  6. Re:Subscriber Fatigue: Right Features, Wrong Price by fermion · · Score: 5, Insightful
    I guess we me it is not the expanding bills, as those come with additional services. It is the long contracts and, at least for cell phones, the difficulty of upgrading.

    For the ISP, the problem is a long list of restrictions. You can do this, can't do that. You have to install this software, and we can redirect you. My favorite is that on SWB, Yahoo will take you a useless ad page, which youmay customize, rather than yahoo.com, which is actually useful.

    For the cell phone, I would use the new services, but it is so hard to upgrade. I have to buy a new phone, sign up for two years, and maybe even pay an activation fee. What the hell do they think? That after several years of staying with the same company I am going renew a plan and then quit after a few months. They have to create a reasonable path so that old customer can migrate to thier new services.

    --
    "She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
  7. Re:Subscriber Fatigue: Right Features, Wrong Price by rmarll · · Score: 5, Insightful

    At my last cell company, the *killer app* apparently was to write software to strip caller ID info from the data stream and charge me to turn off the filter.

    I currently have a mailbox with 3 available message spaces... Not that I mind so much, but does the exra space for a few more messages really cost 5.95 a month?

    I feel like someone has crapped in my well so they can sell me bottled water.

  8. Re:3G by Tim+C · · Score: 5, Funny

    I'm not buying screen savers and ringers that expire in 90 or 120 days

    Your screensavers and tones expire?! I think I begin to see why Americans always seem to be so critical and sceptical of advances in mobile phone technology - expiring downloads, network-locked phones, etc; you guys are being screwed.

  9. Has anyone RTFA or RTFP ? by anti-NAT · · Score: 5, Insightful

    Because I have glossed through it (a number of months ago), and none of the comments up until now show any evidence of people actually understanding Prof Odlyzko's arguments.

    The goal of ATM was to replace network stacks such as TCP/IP, as evidenced by all the different QoS options available (VBR, CBR, UBR etc), as well as all the AAL layers (1 - 5, I've heard a AAL6 might be coming). Switched Virtual Circuits were supposed to be the dominant way connections were set up.

    Why has it failed ? There are primarily two reasons :

    • It is primarily deployed, if not always deployed, by telco customers as Permanent Virtual Circuits. The Telco's love SVCs, as they can then charge per connection setup. Customers love PVCs, as it is then a fixed price service. The customer won. So the SVC mechanisms within ATM are somewhat redundant, as well as the SVC signaling mechanisms.
    • The dominant application of ATM is to run TCP/IP over it. This is a waste of resources, as TCP is providing a lot of the facilities ATM was intended to provide. ATM is incredibly over engineered for the most common service it is being used for, namely, link layer or layer 2 point to point, best effort connections.

    Another technical restriction ATM has is due to the 53 byte Cell size. As bit rates increase, the number of cells per second increase, which increases the number of cell headers per second the ATM device has to process, which then increases the computational requirements of the ATM device. This is putting huge demands on CPU/ASIC technology, such that it is becoming impossible to build an ATM interface that can operate fast enough. For example, you can already get 10Gbps SONET and Ethernet interfaces, but I'm not aware of any 10Gbps ATM interfaces. They may exist, but they are "late to market", and very expensive, when compared to alternative 10Gbps techologies.

    On a related note, the header per second processing issue is also going to be a problem with ethernet in the near future, which one of the reasons why jumbo / 9000 byte ethernet frames is slowly being adopted.

    Finally, a note to those who think ATM is successful just because it is being used. You really need to consider and compare the original goals of the technology verses how it is commonly been used. As ATM typically isn't used at all for what it was designed for, then it is a design failure, and an over engineered one at that.

    We all complain about how much our broadband Internet access costs. Unfortunately, ATM has contributed significantly to those high costs, because the vendors who have sold ATM want to re-coop all their R&D costs for most of the features of ATM that are never used, so they charge high prices for ATM technology. There are a few things ATM does that other technologies don't, and there haven't been any alternatives, so we have been stuck with ATM, and have been stuck paying for its over engineering.

    --
    The Internet's nature is peer to peer - 20050301_cs_profs.pdf