August 2005 - Test - lists.nanog.org

Order of ASes in the BGP Path
by Abhishek Verma 30 Aug '05

30 Aug '05

Hi, Is the order of AS numbers (except for perhaps the first one which denotes the AS the route was originated from) in the AS_PATH in BGP important? In fact, does anybody even care for the first AS number that appears in the Path? AFAIK, AS numbers in the BGP serves two purposes. It helps in loop detection and it helps us count the AS Path length. If this is the case then the order should not really matter much. My question is that whether the operators care if the order, for some reason changes? Eg. Legend: {} denotes the sequence, while [] denotes the set Path {1 2} [3 4] {5} Would somebody mind if this was represented as {1 2 5} [3 4] ? Thanks, Abhishek

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Re: Order of ASes in the BGP Path
by Robert Bonomi 29 Aug '05

29 Aug '05

> Date: Mon, 29 Aug 2005 22:15:26 +0530 > From: Abhishek Verma <abhishekv.verma(a)gmail.com> > Subject: Order of ASes in the BGP Path > > > Hi, > > Is the order of AS numbers (except for perhaps the first one which > denotes the AS the route was originated from) in the AS_PATH in BGP > important? In fact, does anybody even care for the first AS number > that appears in the Path? > > AFAIK, AS numbers in the BGP serves two purposes. It helps in loop > detection and it helps us count the AS Path length. AS_PATH is used for various administrative 'policy' matters, as well. It is not used in the actual routing of data. that functionality is accomplished using only the destination netblock and 'next hop' info. > > If this is the case then the order should not really matter much. Except for standards compliance. <evil grin> Per the RFCs on the subject, if you _receive_ an unordered set from a downstream, you can propogate that unordered set, but you must prepend your AS in the 'ordered' fashion. And you must use the ordered path tagging for any new stuff you generate. > My question is that whether the operators care if the order, for some > reason changes? > > Eg. > > Legend: {} denotes the sequence, while [] denotes the set > > Path {1 2} [3 4] {5} As I understand the specs, that is -not- allowed. an unordered set can appear only as the _last_ element of the AS path list. > > Would somebody mind if this was represented as {1 2 5} [3 4] ? Did the topology change? Or did "somebody" just decide to re-write the AS_PATH elements ? your first illustration would 'apparently' describe a topology on the order of; +-3-+ / | \ 1--2 | 5 \ | / +-4-+ where the latter describes something on the order of: 3 /| 1--2--5-+ | \| 4 Anybody that is 'mapping' interconnections is going to be "unhappy" if the 'representation', and the 'reality' are not consistent. :)

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RE: Katrina could inundate New Orleans
by Hannigan, Martin 29 Aug '05

29 Aug '05

> This post is very OT, but I think events warrant the protocol > violation this time. If you're in New Orleans, I'm sure the > health of > the local internet infrastructure becomes secondary to getting your > ass above sea level... Some of this is on topic. Internet access is as important as the lights or water being on. Right, get out, but it'll be good to see reasonable updates on what's going on utilities wise down there when the weather shifts. -M<

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Reminder - Submissions for NANOG 35 are due next week
by Steve Feldman 29 Aug '05

29 Aug '05

Just a quick reminder that the deadline for proposals for NANOG 35 is Tuesday, September 6. All submissions must be received by nanog-support(a)nanog.org no later than 11:59pm EDT on that date to be guaranteed consideration. (Late submissions will only be considered if space on the agenda is available.) For complete details please see the Call for Presentations at: http://www.nanog.org/mtg-0510/cfp35.html If you have any questions or need further information, Please contact me or nanog-support(a)nanog.org. Steve Feldman NANOG Program Committee Chair

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MPLS security book
by Kim Onnel 28 Aug '05

28 Aug '05

Hello, I've been reading through Cisco press MPLS VPN Security book, too many assumtions about spoofing labels, getting access to core, PE, another VPN,.... in security nothing should be taken for granted, but has there been any real world incidents where such scenarios have been really occuring ? Regards

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RE: Katrina could inundate New Orleans
by Hannigan, Martin 28 Aug '05

28 Aug '05

> > http://hosted.ap.org/dynamic/stories/K/KATRINA_THE_BIG_ONE_LAO > L-?SITE=LABAT&SECTION=HOME&TEMPLATE=DEFAULT Looks like the major hit to occur between 7A/11A Eastern. http://www.weatherstreet.com/CloudsPrecip.htm# -M<

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Katrina could inundate New Orleans
by Fergie (Paul Ferguson) 28 Aug '05

28 Aug '05

Wow. It doesn't look good for New Orleans and surrounding area. Just curious what measures ISP's in the area may have been going through in preparation for this (what appears to be huge) hurricane. - ferg -- "Fergie", a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawg(a)netzero.net or fergdawg(a)sbcglobal.net ferg's tech blog: http://fergdawg.blogspot.com/

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RE: Arbor's technical support contact?
by Hannigan, Martin 28 Aug '05

28 Aug '05

> > How can I contact Arbor's technical support enigneer? > http://www.arbornetworks.com/products_support.php

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Arbor's technical support contact?
by Joe Shen 28 Aug '05

28 Aug '05

Hi, How can I contact Arbor's technical support enigneer? Joe Send instant messages to your online friends http://asia.messenger.yahoo.com

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heads-up: abusat.org registered (!= cbl.abuseat.org)
by JP Velders 28 Aug '05

28 Aug '05

LS, today I had to find out that during my holiday a typo was entered into our mailconfig, we use a bunch of dnsbl's, amongst others the CBL (cbl.abuseat.org) Now, the 'e' from abuse was left out by mistake it seems, so since 07:40 (GMT+2) we suddenly started bouncing everything based on - as it appeared to others - the CBL... :( >From the PIR whois I got: jpv@jp-gp: ~ $ whois -h whois.pir.org abusat.org [ ... ] Domain ID:D107298888-LROR Domain Name:ABUSAT.ORG Created On:28-Aug-2005 05:36:11 UTC Expiration Date:28-Aug-2006 05:36:11 UTC Sponsoring Registrar:Capitoldomains LLC (R1392-LROR) Status:TRANSFER PROHIBITED So, in case anyone else made a typo and didn't notice, you might want to check before you get angry calls about it. This domaingrabber is answering all queries within this zone: jpv@jp-gp: ~ $ dig 1.0.0.127.cbl.abusat.org. A | grep 'IN A ' 1.0.0.127.cbl.abusat.org. 591 IN A 198.65.115.93 I think I have to talk my boss out of taking all my vacation days... He "urged" me to dip in to my (half a year worth) reserve... ;D Kind regards, JP Velders

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