From: Steve Schear (firstname.lastname@example.org)
Date: Fri Mar 03 2000 - 23:42:12 PST
At 11:46 AM 3/3/00 -0800, you wrote:
>At 09:56 AM 03/02/2000 -0500, Steven M. Bellovin wrote:
> >It is worth noting that some bans on running servers are based on
> >not the business model of the provider. In IP over cable systems, there is
> >much less bandwidth available upstream than downstream, and it's much more
> >expensive to add more upstream bandwidth than it is to add downstream
> >bandwidth. If you run a server, you're chewing up a lot of capacity, and
> >affecting your neighbors.
>Excite@Home's ban isn't really based on technology -
>it's using a policy against things that are easy to detect because
>they didn't have good bandwidth-limiting or bandwidth-measurement technology
>and would rather limit their users than resolve individual conflicts.
And that was because they preferred to use the LCD approach to manage their
networks. Even when a cable headend they controlled supported a rich QoS,
such as Com21's ComUNITY, they could/would not support these functions in
their provisioning and control scripts. The result is abuse by a few and
complaints by many.
>USWest apparently has a similar policy for consumer-priced DSL.
>Obviously they need to limit upstream volume (and the newer cable modems
>or head-ends are giving them more tools for that),
>but this not only limits the high-volume porn/warez/mp3 servers,
>and high-volume small-business email servers shipping Powerpoints,
>it also limits web servers with pictures of your kids and cats
>that will only ever be downloaded by your relatives,
>and it limits people who use SMTP email instead of POP3,
>or want to use SSH (or telnet) to log into their home machine from work.
VPNs can work well for this.
>They don't limit MS file-sharing servers - they recommend turning them off
>because they're terribly insecure, but they assume they'll be low volume.
>But they don't limit RealAudio or CU-SeeMe, which are real bandwidth hogs.
>It's a terribly counter-productive policy - the way to get 50 million users
>is for somebody to develop the killer app that makes always-on more useful.
>The way to do that is to let the current million users play around and find it
>(and just hope it isn't Napster :-), which means allowing light-weight
BTW, there are now open-Napster implementations. See http://www.napigator.com/
>The killer app may be a free thing, or a business, or a freeware that
>sells out to MSAOL for big bucks; the cable ISP should welcome all of them.
One of the killer apps is already available. Its called Dialpad. I allows
any Windows PC user to terminate a phone call to a U.S. phone for free,
talking as long as one wishes. (IP-IP connections are also supported.) I
know of several foreign residents who routinely use the service. One of
them, the Arab Emerates, has recently found the gov't controlled ISP
blocking connection to Dialpad's servers. It must already be hurting.
>The related technology issue is "so how much upstream load *do* they
>and "what tools does the system have for scalability and load limiting?".
>Julf's anon.penet.fi ran on a 64kbps line, but web service can be
>a much heavier load, especially if the system forwards pictures.
>I used to run a Crowds server when I had DSL, and it got very little load,
>but if Freenet catches on, it'll have more load, at least unless there
>are lots more users
>And David Honig wrote:
> >How many servers can dance on the head of a pin?
> >How many cable modem operators are pin heads?
>Yow! @Home has delayed cable modem service in my town yet another month :-)
> >What is the definition of 'server' in these contracts? In the law?
>None - it's whatever the sysadmin thinks it might be.
> >Restricting the use of the media should not be legal if the supplier has a
> >government-granted monopoly (as cable ISPs do, and DSL will if the CO isn't
>Cable ISPs haven't had granted monopolies in most places for a few years;
>there are FCC rules requiring towns to open access to the streets for
>competitive cable providers. In practice, they're usually monopolies,
>though overbuild carriers like RCN are starting to add competiting cable
> >Better to act and ask forgiveness then to ask permission first...
>Steve Shear also posted that cable ISPs don't enforce aggressively;
>they mainly respond to complaints. But unless they become universal
>(e.g. include an anonymizer with every copy of Apache),
>remailers, rewebbers and eternity servers are *guaranteed* to generate
>They'll obviously be abused by the usual spammers, harassers, and pranksters,
>but there are people who don't like anonymity and will do the
>Gary B*rn0re act of anonymously slandering themselves and complaining
>to the ISP to get the remailer shut down.
That's why only middleman remailers should be run from private
addresses. Leave the exits to Hotmail, as Ian Goldberg has shown.
>Steve Shear also replied that security and firewalls may be more important
>than the server-vs-client issue. I disagree, at least for cable modem users;
>getting cracked is annoying, but getting shut down hard means that
>you can't run the service\\\\\\\listener.
Fortunately one can put a little backbone into the ISP with a bit of
monkeywrenching. Cable networks are very fragile, especially the upstream
lasers. Inject a few volt p-t-p 25-45 MHz CW signal (using an inexpensive
Radio Shack signal generator) into your home cable system and the upstream
laser will immediately saturate. Make it intermittent and watch the fun begin.
This archive was generated by hypermail 2b29 : Fri Mar 03 2000 - 23:43:02 PST