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redundancy [was: something about arrogance]
by Pedro R Marques 30 Jul '02

30 Jul '02

Brad writes: > I'm probably demonstrating my ignorance here (and my stupidity in > stepping into a long-standing highly charged argument), but I'm > completely missing something. For reasons of redundancy & > reliability, even if you were to buy bandwidth in only one location, > wouldn't you want to buy it from at least two different providers? > If you buy bandwidth from two different providers at two > different locations, this would seem to me to be a good way to > provide backup in case on provider or one location goes > Tango-Uniform, and you could always backhaul the bandwidth for the > site/provider that is down. Several other posters have mentioned reasons why redundancy between 2 different connections to separate providers are not, in most situations, the preferable aproach but i would like to add another point/question... When considering redudancy/reliability/etc it is important to think about what kind of failures do you want to protect against vs cost of doing so. It is my impression, from reading this list and tidbits of gossip, that the most common causes of failure are: - link failure - equipment failure (routers mostly), both software and hardware - configuration errors All of those are much more frequent than the failure of an entire ISP (a transit provider). It is expected, i believe, of a competent ISP to provide redudancy both within a POP and intra-POP links/equipment and its connections to upstreams/peers. As such, probably the first level of redundancy that a origin AS (non-transit) would look at would be with the intent to protect from failures of its external connectivity link and termination equipment (routers on both ends). To do so, one can look at: - 2 external links to distinct providers - 2 external links to the same provider While i can't speak to the economics part of the equation (although i would expect it to be cheaper to buy an additional link than connect to a different provider) from a point of view of restoration, protecting a path with an alternate path from the same provider is certainly an aproach that gives you much better convengence times. This comes from the fact that in terms of network topology, the distance between 2 links to the same upstream is much shorter than 2 links to different upstreams. While, if you protect a path with an alternate path to the same ISP you can expect convergence to occur within the IGP convergence times of your provider, with 2 different providers you need global BGP convergence to occur. This gets to be longer dependent on how topologically distant your 2 upstreams are... for instance attempting to protect a path to an ISP with very wide connectivity with a protection path from one with very limited connectivity would be a particularly bad case as you would have to wait for the path announced by the larger ISP to be withdrawn n times from all its peering points and the protection path to make its way through in replacement. It is counter-intuitive to me what i perceive to be the standard practice of attempting to multi-home to 2 distinct providers by origin-only ASes... from several points of view: convergence times, load on the global routing system, complexity of management, etc, dual connectivity to different routers of the same provider (using distinct physical paths) would seem to me to make more sense. Unless the main concern is that the upstream ISP fails entirely... which given the fact that it tends to have frontpage honors on the NYTimes this days does not apear to be an all to common occurence (i mean operationally, not financially - clarification added to dispel potential humorous remarks). So, my question to the list is, why is multi-homing to 2 different providers such a desirable thing ? What is the motivation and why is it prefered over multiple connections to the same upstream ? Is the main motivation not so much reliability but having a shorter as-path to more destinations ? This would apear to me to be a clear advantage since that doesn't necessarily reflect in better qualitify of interconnection. My apologies in advance if these seem to be stupid questions... thanks, Pedro.

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RE: OC-768 availability?
by Rowland, Alan D 30 Jul '02

30 Jul '02

Compton, CA, US and Sealand would be the giveaways. Best regards, _________________________ Alan Rowland Who lives just south of Compton -----Original Message----- From: Scott Weeks [mailto:surfer@mauislanwanman.com] Sent: Monday, July 29, 2002 4:31 PM To: Williams, Ken Cc: 'dalph(a)hushmail.com'; nanog(a)nanog.org Subject: RE: OC-768 availability? No, he's not for real. It's a satire in the likes of Bandy Rush and such. Children need to have their fun... scott On Mon, 29 Jul 2002, Williams, Ken wrote: : : hah 2621 rockin oc-192 are you for real? : : -----Original Message----- : From: dalph(a)hushmail.com [mailto:dalph@hushmail.com] : Sent: Monday, July 29, 2002 4:10 PM : To: nanog(a)nanog.org : Subject: OC-768 availability? : : : : : Hello, : : I am currently running a network of cisco 2621s with the OC-192 NM for my : upstream connections. The internal network links are a mixture of K56Flex : modems and GRE tunnels. : : I am looking to upgrade to OC-768 real soon now and am wondering what the : prospects are for OC-768 availability on the 2621 platform. I've found the : 2621 to be rock-solid, except when I ping it, so I'd like to keep my network : on that platform if possible. : : In addition, if anyone knows the availability of OC-768 circuits between the : following cities I'd appreciate any fiber maps and an approximate price : range: : Ottawa, ON, CA : Midland, ON, CA : Goderich, ON, CA : Toronto, ON, CA : Compton, CA, US : Sealand : : At each site I plan to announce a /24 from a /20 I was allocated so if : everyone could please update their prefix filters now that would be great. : : Thank you. : : -- Dalph Roncaster : : Communicate in total privacy. : Get your free encrypted email at https://www.hushmail.com/?l=2 : : Looking for a good deal on a domain name? : http://www.hush.com/partners/offers.cgi?id=domainpeople :

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Re: routing table size
by Stephen J. Wilcox 30 Jul '02

30 Jul '02

I've a feeling that the fact that everyone shares at least the view that a /24 is minimum helps to contain the routing table. (even if there are still thousands of /24 announcements) If a significant number of providers starting accepting any prefix then the others would need to follow (else they'd get no transit traffic as it will always prefer the most specific). This really would lead to route explosion! I guess the counter argument is that you'd still get the same number of announcements at longer prefixes as there are only lots of /24s as its the current shortest (if you catch my drift here). But I doubt it is quite that straight forward and there would be a growth in announcements.. Steve On Sat, 27 Jul 2002, David Schwartz wrote: > > > >I've never suggested accepting /25's thru /32's. I'm wondering if the > >people saying I should not de-aggregage my /20 actually practice what they > >preach and filter /24's and don't globally announce /24's from their > >customers. > > > >-Ralph > > What's wrong with announcing routes from your customers? Even /32s if you > want. Only those people who choose to accept them will be affected by them > and anyone who you have a BGP session with can insist you filter them out. > Treating different situations as if they were the same is not practicing what > you preach. > > DS > > > > > >

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OC-768 availability?
by dalph＠hushmail.com 30 Jul '02

30 Jul '02

Hello, I am currently running a network of cisco 2621s with the OC-192 NM for my upstream connections. The internal network links are a mixture of K56Flex modems and GRE tunnels. I am looking to upgrade to OC-768 real soon now and am wondering what the prospects are for OC-768 availability on the 2621 platform. I've found the 2621 to be rock-solid, except when I ping it, so I'd like to keep my network on that platform if possible. In addition, if anyone knows the availability of OC-768 circuits between the following cities I'd appreciate any fiber maps and an approximate price range: Ottawa, ON, CA Midland, ON, CA Goderich, ON, CA Toronto, ON, CA Compton, CA, US Sealand At each site I plan to announce a /24 from a /20 I was allocated so if everyone could please update their prefix filters now that would be great. Thank you. -- Dalph Roncaster Communicate in total privacy. Get your free encrypted email at https://www.hushmail.com/?l=2 Looking for a good deal on a domain name? http://www.hush.com/partners/offers.cgi?id=domainpeople

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custom dialup kits
by Miguel Mata-Cardona 30 Jul '02

30 Jul '02

who make these kits nowaday? Had some contacts, but most of them are gone. URL or contact email will be very appreciated. -- Miguel Mata-Cardona Intercom El Salvador mmata(a)sv.intercomnet.net

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RE: custom dialup kits
by Rowland, Alan D 30 Jul '02

30 Jul '02

Not sure what you're looking for here. Phone jack converters? Available at many airport gift shops and a Google search results in http://kropla.com/sources.htm Best regards, _________________________ Alan Rowland -----Original Message----- From: Miguel Mata-Cardona [mailto:mmata@sv.cciglobal.net] Sent: Tuesday, July 30, 2002 8:21 AM To: nanog(a)merit.edu Subject: custom dialup kits who make these kits nowaday? Had some contacts, but most of them are gone. URL or contact email will be very appreciated. -- Miguel Mata-Cardona Intercom El Salvador mmata(a)sv.intercomnet.net

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Re: verio arrogance
by Ralph Doncaster 30 Jul '02

30 Jul '02

> (Apologies if this is flogging a dead horse, but some messages are worth > repeating, if for no other reason than to illustrate the down side of > not understanding the proper rationale for CIDR.) I thought the dead horse was the conclusion that small ISPs should use whatever means the ARIN rules allow in order to get PI space. Having used provider-assigned space for a couple years, I can firmly say it sucks. Even if I had to talk to every tier-1 to get my de-aggregates accepted, it would be MUCH less hastle than having PA IP space. And your suggestion has technical deficiencies as well. I have a leased line between Toronto and Ottawa, so I want to announce my Ottawa IPs to my Toronto transit provider as well as an Ottawa transit provider. And the reverse for the Toronto IPs. My understand is trying to punch holes in PA space is much more difficult than de-aggregating ARIN PI space. -Ralph

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RE: redundancy [was: something about arrogance]
by John Ferriby 30 Jul '02

30 Jul '02

> You cannot as easily be held hostage. I have consulted for > a few ISPs and > have my share of war stories. > > Here's a (true!) example. One day, a certain head of a > fairly large ISP > decided that he wouldn't route traffic to or from IPs he had > assigned that > didn't reverse resolve because he felt it was imperative that > people be able > to find network contacts in this way (I think he got sick of > being the one to > get the abuse emails). He told my client three days before implementing a > sweep and filter. He had the equivalent of about 38 /24s from this ISP > distributed over about 180 customers, they were his sole uplink. [SNIP] Often overlooked is the redundancy in business processes. We tend to view events with an external-forces engineering perspective while frequently the culprits are uninformed decisions, knee-jerk reactions and opportunism by humans at our vendors. (Not to downplay other risks.) -John -- John Ferriby - PGP Key: www.ferriby.com/pgpkey

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Re: OC-768 availability?
by blitz 30 Jul '02

30 Jul '02

I heard that as well, as well as holographic processing...can't remember who however, but Lucent (or whoever they are this week) or Nortel (presently circling the drain) come to mind.. At 19:53 7/29/02 -0700, you wrote: >Wasn't one of the major switch companies working on a system of bubbles. > <seriously> I'm not sure if it was foundry or Juniper or who but >someone was trying to route packets or rather switch packets in a device >at high speed by using bubbles to reflect and switch the light instead >of converting to electrons. > >On Mon, 29 Jul 2002, blitz wrote: > > > > > Seriously, I don't see OC768 coming online en masse until they get the > > kinks worked out of optical switching. The transit times are so short thru > > the innards, in the order of picoseconds, that electronics is way too slow > > to perform such mundane tasks like determining where a packet is supposed > > to go. > > Thus, all this will require optical computing to be available cheaply > and a > > lot more widespread than it is now. Cross your fingers and hope for a > > quantum breakthrough... > > OC192 is already pushing the limits of present technology. > > And add to that, the sorry state of the major players in telecom, and I > > don't think you'll see them willing to pony up an investment in something > > like that until it's well established. > > A typical egg/chicken situation...... > > > > > > > > At 16:10 7/29/02 -0700, you wrote: > > > > > > >Hello, > > > > > >I am currently running a network of cisco 2621s with the OC-192 NM for my > > >upstream connections. The internal network links are a mixture of K56Flex > > >modems and GRE tunnels. > > > > > >I am looking to upgrade to OC-768 real soon now and am wondering what the > > >prospects are for OC-768 availability on the 2621 platform. I've found > the > > >2621 to be rock-solid, except when I ping it, so I'd like to keep my > > >network on that platform if possible. > > > > > >In addition, if anyone knows the availability of OC-768 circuits between > > >the following cities I'd appreciate any fiber maps and an approximate > > >price range: > > >Ottawa, ON, CA > > >Midland, ON, CA > > >Goderich, ON, CA > > >Toronto, ON, CA > > >Compton, CA, US > > >Sealand > > > > > >At each site I plan to announce a /24 from a /20 I was allocated so if > > >everyone could please update their prefix filters now that would be great. > > > > > >Thank you. > > > > > >-- Dalph Roncaster > > > > > >Communicate in total privacy. > > >Get your free encrypted email at https://www.hushmail.com/?l=2 > > > > > >Looking for a good deal on a domain name? > > >http://www.hush.com/partners/offers.cgi?id=domainpeople > >

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Qwest to Restate Earnings
by Allan Liska 30 Jul '02

30 Jul '02

http://story.news.yahoo.com/news?tmpl=story&u=/ap/20020729/ap_on_bi_ge/qwes… Not too much of a surprise. allan -- Allan Liska allan(a)allan.org

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