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Could the Internet Be Taken Down In 30 Minutes?

Posted by ScuttleMonkey on from the millions-of-voices-suddenly-cried-out-in-terror dept.

GhostX9 writes "Tom's Hardware recently interviewed Dino A. Dai Zovi, a former member of Sandia National Labs' IDART (the guys who test the security of national agencies). Although most of the interview is focused on personal computer security, they asked him about L0pht's claim in 1998 if the Internet could still be taken down in 30 minutes given the advances on both the security and threat sides. He said that the risk was still true."

52 of 289 comments (clear)

  1. Yes by 2.7182 · · Score: 5, Insightful

    By a nuclear war for example.

    1. Re:Yes by techprophet · · Score: 3, Funny

      Or a new strain of rapidly spreading electricity-consuming tiberium.

      Or me.

    2. Re:Yes by Anonymous Coward · · Score: 3, Insightful

      Too expensive. How about 2 broken routers: http://tech.slashdot.org/article.pl?sid=09/02/16/2233207

    3. Re:Yes by Chris+Burke · · Score: 4, Funny

      By a nuclear war for example.

      Why go to such extremes?

      root@internet# shutdown -h +30 "Teh Intarwebs are going down!"

      --

      The enemies of Democracy are
    4. Re:Yes by ElizabethGreene · · Score: 4, Insightful

      To break the "whole" internet takes some doing. That said, a large scale distributed dns reflection attack or any number of other attacks can turn off large chunks of the internet more or less at will. Thirty minutes seems very optimistic, if the zombies are in place prior to the attack.

    5. Re:Yes by rpmayhem · · Score: 5, Funny

      root@internet# shutdown -c "I'm still reading slashdot you insensitive clod!"

  2. All it needs is a giant Slashdotting by Anonymous Coward · · Score: 5, Funny

    Just visit url://internet

    1. Re:All it needs is a giant Slashdotting by Chris+Mattern · · Score: 5, Funny

      Firefox tells me it doesn't understand URLs. I'd better just stick to HTTPs.

    2. Re:All it needs is a giant Slashdotting by ozbird · · Score: 3, Funny

      That's because Firefox saves thar Interwebs. IE would probably give you an animated "It looks like you're trying to take down the Internet" helper.

  3. Internet Backbone DDOS in 2002 by eldavojohn · · Score: 5, Insightful

    In 2002 4 or 5 of the 13 root servers were big news ... although we've come a long way since then, I think the integrity of the internet still depends on these things.

    Every so often we get reports that the internet is a rickety old jalopy on it's last leg.

    Given this impression and add to it the fact that the botnets seem to grow in tandem with the internet, I wouldn't be surprised to see an attack take her down in 30 minutes although I'm no expert. I think 30 minutes is a generous amount of time if one of the larger botnets turned its attention on the root servers for a DDOS attack. You'd have some fail overs and some courageous engineer might save the day but I'd put my money on the bad guys.

    I would be surprised if it was down for more than 24 hours following that though.

    --
    My work here is dung.
    1. Re:Internet Backbone DDOS in 2002 by afidel · · Score: 4, Insightful

      The way to fix it would be egress filtering where all consumer class lines were barred from directly querying the root servers. Would suck greatly for anyone who wanted or needed to run their own resolver, and would break the original end to end design of the internet, but it would be the most likely response to the threat. The ISP's would love it too since it would allow them to have a captive audience for their ad laden DNS servers.

      --
      There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
    2. Re:Internet Backbone DDOS in 2002 by Shakrai · · Score: 5, Interesting

      I think 30 minutes is a generous amount of time if one of the larger botnets turned its attention on the root servers for a DDOS attack

      I think you are overlooking a two things:

      1) There's a lot more than 13 root servers nowadays. Many of the servers are mirrored using anycast. Wikipedia had a total of 123 in 2006 so it's a safe assumption that there are even more today.

      2) Even if you could render the root servers inaccessible, this doesn't "take down" the internet. Many sites would still be accessible until their DNS cache entires timed out in the nameserver that you use (likely your ISP). A lot of sites set short timeouts on the www 'A' record (for load balancing purposes) but long timeouts on the 'NS' records for the domain. In this scenario your nameserver would still know where to go to get the 'A' record and wouldn't need to consult with the root servers.

      Those caches wouldn't last forever but it would seem to offer enough time to deal with the DDOS. The internet would have limited functionality for awhile but it wouldn't "go down". Many operations (site to site VPNs for example) might not even notice.

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
    3. Re:Internet Backbone DDOS in 2002 by Lumpy · · Score: 3, Informative

      Nope if you take out ALL The root servers right now I'll still be able to get around on the internet. My servers will still serve up information. my clients will still work.

      Do it get to use the for dummies name resolution? nope.

      If I type in 74.125.67.100 in my browser, google still shows up.

      granted everything in google is useless as they dont log the IP addresses, but that's moot for me. PLUS I can always go to one of the alternate DNS servers and use them. or my local cache... that would work for weeks without the root servers.

      --
      Do not look at laser with remaining good eye.
    4. Re:Internet Backbone DDOS in 2002 by six · · Score: 4, Informative

      root DNS != Backbone

      You can DDOS a server, a network, even big routers, but you can't DDOS the internet.

      Cutting random cables here and there won't work either, at most you're going to isolate parts of the net.

      The only way to take down the internet in 30 minutes is to exploit vulnerabilities in the BGP core routing protocol and announce netblocks that somehow (that's where something has to be exploited, bypassing filters, smaller blocks and routing costs considerations) takes the priority over other routes for every router that receives the announce.

      Not saying that's impossible, but still tough ...

    5. Re:Internet Backbone DDOS in 2002 by Shakrai · · Score: 4, Interesting

      I'm not rude enough to run my own nameserver at home.

      Out of curiosity, why is that 'rude'? Are the root servers overloaded or something? I've always run my own nameserver and aside from a few times when I messed around with linking it to work, I've usually had it going directly to the source. Should I re-evaluate this practice?

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
    6. Re:Internet Backbone DDOS in 2002 by afidel · · Score: 3, Informative

      Are you behind a consumer grade firewall appliance ala Netgear or Linksys? If you are then you are almost 100% guaranteed to be more at risk running your own resolved than you are forwarding to a decent ISP run setup. The reason is that none of the consumer grade firewalls support source port randomization meaning you are very vulnerable to DNS cache poising attacks.

      --
      There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
  4. It can be taken down much faster now. by Anonymous Coward · · Score: 5, Informative

    http://www.networkworld.com/news/2009/040209-obama-cybersecurity-bill.html

    A federally enabled Internet kill switch will place an Internet Off Button in the White House which can be used to instantly deactivate the Internet in case of an emergency, such as the plebes getting riled up. This bill, introduced to the Senate on April Fools, is expected to pass.

    1. Re:It can be taken down much faster now. by Leafheart · · Score: 4, Insightful

      Your Internet maybe, not mine. At least, not because of that.

      --
      --- "When you gotta do something wrong. You gotta do it right. (Fighter)"
  5. Re:true by Anonymous Coward · · Score: 5, Funny

    In 30 minutes?

    You're doing it wrong.

  6. Re:nah. by canajin56 · · Score: 5, Informative

    Not true! ARPANET was designed as it was because there were only a few super computing sites at the time, and they were separated by quite a bit. The redundancy comes in to play only because they didn't want to lose important access if a router broke somewhere, as they are wont to do. All it was designed for was to survive a single point of failure. But even that is distorted. Just because ARPANET was designed that way decades ago, doesn't mean that large corporations decided to keep with that philosophy when they took over!

    --
    ASCII stupid question, get a stupid ANSI
  7. (Job) security by Anonymous Coward · · Score: 5, Interesting

    Guy who works in security testing wants people to believe that the state of internet security is OMGcritical? Shouldn't this be tagged "jobsecurity" rather than "security"?

  8. 30 mins might be optimistic by Minupla · · Score: 5, Interesting

    Assuming a vulnerability is exploited in BGP, the internet would go bibi in a hurry. That's all our eggs in one basket, and it's a fairly rickety basket. There's still a lot of trust inherent in the BGP fabric and trust is a 4 letter word to anyone who deals with infrastructure security.

    Min

    --
    On the whole, I find that I prefer Slashdot posts to twitter ones because I don't get limited to 140 chars before
    1. Re:30 mins might be optimistic by spacerog · · Score: 5, Interesting
      Actually if I remember correctly the specific flaw that we discovered waaay back in the olden days of 1999 (or was it 98?) was with the Border Gateway Protocol which would cause a cascade router failure. We estimated best case scenario that large chunks of the Internet could be unreachable for up to 12 hours and worst case could be down for several days.

      The really funny thing about all this is that after Senator Thompson and the Government Affairs committee was finished pimpimg us out as media whores several unrelated people approached us and said "Hey, where you thinking of taking the net down this way..." And we would say "No, that's not what we thought of but your idea would probably work just as well."

      The thing is many of those ideas are still valid. The global Internet network is a rickety piece of technology held together with bubble gum and bailing wire. If it wasn't for the fact that people are actively trying to keep it operational I fear it would fall apart under its own weight in a very short amount of time not to mention if someone actually wanted to take it down.

      - Space Rogue
      http://www.lopht.com
      http://www.spacerog.net

    2. Re:30 mins might be optimistic by vlm · · Score: 4, Informative

      BGP by design trusts in routing settings being honest... just program a router with can't-get-there-from-here routes, and you'll down the surrounding area's Internet speed, or even connections.

      No, no one trusts their peers anymore and their configs reflect that. Not since at least the 90s. Since before I started doing BGP support, everyone has filtered their customers routes. WAY WAY too many people try to redistribute 10/8 from their IGP, or maybe try to send us a 0/0. And unscientifically, I'd say about 25% of newbie BGP admins think they own their previous ISPs IP space... so if old ISP gave them 1.2.3/24 they'd ask us to modify our filters to allow the /24, we'd check (have to check each and every customer every time) and see its part of their old ISP's /18, and we'd educate them.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    3. Re:30 mins might be optimistic by ahabswhale · · Score: 3, Insightful

      I call bullshit.

      Every so often you hear about how easy it would be to take down the internet. Yet, it has never happened. It hasn't even come close to happening. I don't doubt it's possible but if it were so easy, it would have been done by now. Some a-holes would have done it just for grins or to prove they could do it. Remember, the world is filled with a-holes.

      Finally, people confuse DNS with the Internet. DNS is a feature of the Internet -- it is not THE Internet.

      --
      Are agnostics skeptical of unicorns too?
    4. Re:30 mins might be optimistic by NeutronCowboy · · Score: 4, Insightful

      You seem to underestimate the blood, sweat and tears that goes into keeping networks alive. Yes, some assholes could take it down in a heartbeat if everyone would just let them. Fortunately, there are a good chunk of smart people who work tirelessly so that this doesn't happen. So far, so good. the problem: the good guys need to win every time to be seen as successful. The bad guys only need to win once.

      --
      Those who can, do. Those who can't, sue.
    5. Re:30 mins might be optimistic by Fred+Ferrigno · · Score: 3, Insightful

      Isn't it the other way around? The people who say the Internet is a house of cards just waiting for a stiff breeze to bring it down are the ones underestimating the blood, sweat and tears that go into keeping networks alive. It's like saying banks would be trivial to rob if there weren't those pesky guards there to stop you.

    6. Re:30 mins might be optimistic by BitZtream · · Score: 3, Insightful

      The large scale providers filter bgp input from their smaller peers. You have to be 'one of the big boys' before you get to pass AS numbers through to the backbone without telling them about it first.

      You might get by with it if you're peering with some smaller provider, as I have in the past, but the end result is that you still have to get them to talk to the real backbone providers to let your AS numbers out.

      So while BGP could cause problems if you got a provider high enough up the food chain the chance of that is highly unlikely, and the monitoring systems in place would detect this and alert on it before it had spread across the entire internet anyway. It would probably effect a good majority of the Internet before fixed, but it wouldn't really last long outside of the tiny area where it started.

      When this sort of thing happens, the backbone providers have no problem turning you off to resolve the problem immediately.

      --
      Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
    7. Re:30 mins might be optimistic by hr+raattgift · · Score: 3, Informative

      That really depends on what the vulnerability is.

      There are several implementations of BGP from different vendors and at least two open source implementations. The protocol is also relatively simple. Consequently it's hard to imagine a vulnerability that is structural within BGP such that enough partitioning happens to make large the Internet unusable.

      In the early 1990s there was a moment where there was a very large partition when AS Path prepending was used for the first time. Cisco routers did not mind the back-to-back duplicate AS. Proteon, Wellfleet and some other implementations discarded the NLRI (prefix/mask + routing information) as part of routing-information-loop avoidance. Gated-derived routers had different approach in its NLRI loop-avoidance code, and rather than use the NLRI or discard that one update, it dropped the TCP session figuring that there was a data corruption bug. The result: BGP sessions between "core" IOS-talking routers and "core" gated-derived routers bounced up and down for a while. This affected most of the exterior routing gateways of ANS, which operated the NSFNET Backbone Service at the time.

      This sort of "reset" policy is now known to have been a serious mistake and now is very rare.

      Also in the early 1990s there was a hardware interaction problem involving Cisco 7000-series routers equipped with Silicon Switching Processor cards. A "covering" prefix arriving via any routing protocol -- typically BGP -- would cause all the "covered" (longer match of the same prefix) to be deleted with demand-population bringing those routes back into the radix tree like data structure. Demand population used the same CPU that TCP ACK processing and other activities used, so a router in the "core" with a relatively full routing table and a high packet per second arrival rate of a mix of prefixes (as in "core" routers generally) would simply melt down. This would starve timer-sensitive activities like TCP ACKing and processing the BGP protocol state machine. This in turn led to BGP sessions resetting due to time-outs, which in turn reduced the traffic load substantially on the melting-down router. This would "thaw" the router enough that it would bring the BGP sessions back up long enough to receive a covering prefix, and so forth in a loop. This crippled one very large "tier 1" ISP for an hour and change.

      There have been a number of minor "ouchies" related to information obtained from BGP neighbours in the years since, with the most embarassing ones having to do with specific implementations' reactions to very long data sets (e.g. extremely large AS_Set attributes, extremely long AS Paths).

      There was also concern some years ago (late 1990s) about the frequency of BGP updates, and that a series of actors publishing up/down/up/down transitions as fast as they could might lead to a router "meltdown" with consequences along the lines of the situation described a couple of paragraphs up. This was considered a long term possibility, and as a result a couple of different approaches evolved suppress oscillating prefixes or blocks thereof at a level much lower than that where BGP's fundamentally built in mechanisms (TCP window sizes and fundamental NLRI/RIB processing speeds) would kick in.

      The modern BGP "basket" is much less systematically rickety; the systemic ricketyness is the result of BGP being fundamentally being a "push" distribution of vectors rather than a "pull" acquisition of nonlocal (but widely distributed) connectivity and policy maps (as happened when one fed desired map data from USENET's u.* hierarchy into pathalias, for example, using one or more "smarthosts" as the equivalent of IP's 0.0.0.0/0 default).

      Sadly, because the "push" NLRIs are not easily cryptographically signed by the source site (unlike PGP around a UUCP/USENET map file or even around an individual entry) there is still a requirement to trust your largest neighbours, although in the early 1990s the remained ANS's Policy Routing DataBase

  9. Re:nah. by interkin3tic · · Score: 5, Funny

    Actually, this is exactly what it's supposed to survive.

    Well, I'm reasonably certain my computer can't withstand a nuclear attack, and I don't think most porn stars are radiation-resistant, so it's really trivial to me whether or not there is still an internet after a nuclear war.

  10. Depends on who you ask... by imajinarie · · Score: 5, Funny

    According to my parents and people in my office, the Internet is occasionally down for several hours at a time. Fortunately, they have the ability to reboot it when necessary.

  11. Re:Is this news?? by myVarNamesAreTooLon · · Score: 5, Funny

    All it would take is the right cables to be cut for the internet to go down. Perhaps with a rented backhoe even.

    A single backhoe might have some trouble getting the entire internet in 30 minutes. What's the top speed on those things?

  12. it was demonstrated last year by Paralizer · · Score: 4, Informative

    When Pakistan decided to block youtube they inadvertently caused a global routing blackhole. The internet is built with the BGP routing protocol, which is based on trust. You trust that your peers will advertise correct routes. If they don't then you get misinformation like in the Pakistan/Youtube situation and it spreads, pretty soon everyone thinks going through Pakistan is the best way to reach youtube so all traffic (or almost all) goes there, then Pakistan simply drops those packets.

    Of course this was an accident, but a malicious attack could simply advertise lots of incorrect routes and hose up everything ... at least for a little while.

    1. Re:it was demonstrated last year by vlm · · Score: 3, Insightful

      The internet is built with the BGP routing protocol, which is based on trust. You trust that your peers will advertise correct routes.

      Only and exclusively amongst the tight knit community of tier 1 providers. No one accepts unfiltered routes from their customers. (except for unintentional mistakes).

      Also, You Tube is not "the internet" as in "the entire internet". Good luck advertising a 0/0 route, even amongst tier 1 ISPs.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  13. Re:nah. by ParanoiaBOTS · · Score: 5, Funny

    OK, then what about by a Cylon invasion? (Which of course, would begin with a nuclear strike.) I doubt that our toaster children would have any trouble with Mccafree or Norton products.

    In my experience if we did have a Cylon invasion McAfee and Norton may be our ONLY defense. Upload it and watch as they can no longer function

  14. CME by rthille · · Score: 4, Interesting

    http://www.businessinsider.com/could-the-sun-destroy-the-earth-2009-3

    Coronal Mass Ejection, a big enough one could wipe out all life on earth, and fry all the electronics.

    --
    Awesome furniture, accessories and cabinetry in Santa Rosa, CA: http://humanity-home.com/
  15. Prevent Over Logging by teko_teko · · Score: 3, Funny

    Today we take the Internet for granted, but it could go down any time from over logging. We have to prevent this by using the Internet when truly necessary, and to only view Internet porn twice a day... max.

  16. NAH by neo · · Score: 4, Interesting

    "A memorandum published by the DoD in March 1982 declared
    that the adoption of TCP/IP as the DoD standard host-to-host
    protocol was mandatory and would provide for "host-to-host
    connectivity across network or subnetwork boundaries."

              Military requirements for interoperability, security,
              reliability and [b]survability[/b] are sufficiently pressing to
              have justified the development and adoption of TCP and IP in
              the absence of satisfactory nongovernment protocol
              standards."

    Emphasis mine.
    http://www.columbia.edu/~rh120/other/tcpdigest_paper.txt

    1. Re:NAH by iluvcapra · · Score: 4, Insightful

      The DoD also approved the Space Shuttle's final dimensions on the basis of $100/lb launch costs and a constant schedule of military payloads... I think if you were to hand the DoD a purchase order for a pallet load of marshmallow peeps, they'd only be to happy to certify their nuclear/chem/bio survivability and tactical necessity. They just like to buy toys, and nobody questions them about wether they really need something, and nobody ever tests them to make sure they really use it...

      At least in this case we ended up with the Internet, and not the spaceplane-that-wouldn't-die-and-syphons-science-money.

      --
      Don't blame me, I voted for Baltar.
    2. Re:NAH by truthsearch · · Score: 3, Funny

      I think if you were to hand the DoD a purchase order for a pallet load of marshmallow peeps, they'd only be to happy to certify their nuclear/chem/bio survivability and tactical necessity.

      That would be a mistake. They should only certify Twinkies.

      If Family Guy has taught me anything, it's that everyone should go to the nearest Twinkie factory in the event of a nuclear holocaust.

      --
      Developers: We can use your help.
    3. Re:NAH by BarryJacobsen · · Score: 5, Funny

      If Family Guy has taught me anything, it's that everyone should go to the nearest Twinkie factory in the event of a nuclear holocaust.

      If Family Guy has taught you anything, then may god have mercy on us all.

      --
      Track your TV Shows with your iPhone - FREE
    4. Re:NAH by Verdatum · · Score: 3, Funny

      "Well, let's say this Twinkie represents the normal amount of psychokinetic energy in the New York area. Based on this morning's reading, it would be a Twinkie thirty-five feet long, weighing approximately six hundred pounds."

      "That's a big Twinkie."

  17. Re:nah. by rcamans · · Score: 4, Funny

    The stars may not survive, but their videos could in a datastore underground. And your computer could survive in a bomb shelter. Underground. You know, where you live. In your mama's basement.
    Heh heh

    --
    wake up and hold your nose
  18. I am ready for the DNS takedown! by belloc1 · · Score: 5, Funny

    I have all my most important sites IP addresses written on Post It notes all over my wall.

    Bring it!

  19. Re:Is this news?? by ckaminski · · Score: 4, Insightful

    If you want a ride bouncier than the storm chasers in KC10s you can do about 22-25 mph in a Ford 555 (80's vintage backhoe). And that's on a decently paved street. You hit a decent pothole and you better have your feet on the posi button because when your steering wheels hit ground again, you're likely to zoom into traffic or onto the sidewalk.

    It's why I only ever did over-street travel in ours at night. Then again, backhoe's are naturally overbalanced to the rear, I never did try to get our straight farm tractor up to speed on surface streets.

    I've popped a wheelie in exactly two tractors in my day, one a backhoe, another a dozer. Sort of frightening when you do it for the first time and aren't expecting it.

  20. Re:YES!! by vlm · · Score: 5, Interesting

    Take BGP for example. Very little security in it.

    Sounds like somebody not involved in actual BGP work and/or just scaremongering (worship me because I say scary things).

    Nobody configures their peers using dns addresses. Doesn't everyone use md5 hashes? Doesn't everyone filter their customers routes?

    I did "most of" the customer side BGP at an ISP for "years" with quite a few customers... if every time someone redistributed 0/0 or 10/8 to us we took down the internet, frankly, it would have been down most of the time. Not to mention people whom thought their old providers IP space was their own (as opposed to actual ARIN space)

    Then there's the guys who prepend like a hundred times, always good for a laugh or two.

    Folks whom think they can take down global BGP by flapping their routes a couple times and don't even know what route dampening is... well...

    Now, yeah, one bad dude could take over one router and maybe temporarily down one ISP that is run by fools who don't follow the "rules", but one badly run ISP out of bazillions is not "the internet".

    Overall, I'd say out of 30K AS, of which at least 50% don't really know what they're doing, yet they still can't take the sucker down, god knows I've seen everything tried at least once, so a couple black hats don't even have a chance.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  21. Ask my girlfriend . . . by PolygamousRanchKid+ · · Score: 5, Funny

    . . . she accuses me of "turning off" or "breaking the Internet" at least once a day.

    That's the power that you get with 57 levels of Slashdot Achievements. A big switch labeled "Internet On/Off."

    --
    Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
  22. Re:nah. by freyyr890 · · Score: 5, Funny

    OK, then what about by a Cylon invasion? (Which of course, would begin with a nuclear strike.) I doubt that our toaster children would have any trouble with Mccafree or Norton products.

    In my experience if we did have a Cylon invasion McAfee and Norton may be our ONLY defense. Upload it and watch as they can no longer function

    You're horrible. Not even the Cylons deserve Norton and McAfee.

  23. Re:true by mollymoo · · Score: 4, Funny

    I think your're confusing your childhood with a "yo momma" joke.

    --
    Chernobyl 'not a wildlife haven' - BBC News
  24. Re:nah. by peragrin · · Score: 5, Funny

    I'm saving my copy of windows ME just for the cylon revolt.

    --
    i thought once I was found, but it was only a dream.
  25. Re:YAH!! by 644bd346996 · · Score: 3, Informative

    I'm pretty sure that not having a single point of failure was considered part of "reliability" even back then.

  26. Re:We need to mesh more by vlm · · Score: 3, Insightful

    Maybe "forcing" is a bit strong, but ISPs should definitely be encouraged to do so. Every packet which does not go over centraliced portions of the net makes it more stable.

    1) Maybe if I won't peer with him, he will hire me as an upstream and I'll make money. Extra funny if both sides try the same strategy. Even funnier if one side was recently paying the other, and now refuses and/or is going bankrupt.

    2) My cheap router doesn't have enough memory/CPU/whatever to peer with EVERYONE at the IX, somebody is going to get cut. Or maybe I have the hardware, but the guy I'd like to peer with simply does not.

    3) Maybe the IX charges $x for each peering connection (they gotta pay their bills somehow). So, if that peer is only worth $y of paid upstream traffic, and $x > $y, then ...

    4) ISP "Y" does not have enough capacity outta the IX to handle the traffic I'd like to send them. (no one ever admits in public they are the ones whom don't have a large enough pipe to the IX, its always the other guys)

    5) "X"-IX is just icky and flaps all the time and drops packets. Now that is good enough for our connection to Afghanistan Telco because we can blame the problems caused by the IX, on the satellite, but our customers will not tolerate those problems when connecting to skype, so no peering for skype at that IX! Bonus points if "X"-IX is on the other side of the planet from our techs, and/or their support sucks.

    6) I'm secretly a middle school girl whom runs BGP at ISP "X" (sounds like an Anime series?). Now, I heard, that she said, that he read on the bathroom wall, that the middle school girl whom runs BGP at ISP "Y" said my network sucks, so ISP "Y" is soooooo off my myspace friends list and livejournal and AIM and also I'm not inviting them to my peering party. Now personally, I believe this scenario accurately represents about 99% of all peering disputes.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger