January 2004 - Test - lists.nanog.org

Re: Any 1U - 2U Ethernet switches that can handle 4K VLANs?
by sthaug＠nethelp.no 27 Jan '04

27 Jan '04

> ISL _DOES NOT CHANGE_ packet size. An 802.1q tag adds 4 bytes to the Ethernet frame. ISL encapsulation adds 30 bytes to the Ethernet frame. Steinar Haug, Nethelp consulting, sthaug(a)nethelp.no

4 4

Re: Outbound Route Optimization
by Michael.Dillon＠radianz.com 27 Jan '04

27 Jan '04

>What is broken for one provider and fixed at another may very well break >something else that was working before at the first provider, yes? Besides >the difficulties of assigning a true metric to the overall reachability of >a /8 or any aggregate for that matter ("ok we decreased rtt by 20ms to >these 3 destinations doing 15Mbps each but we increased rtt to this other >destination doing 40Mbps by 60ms so we're better right?"), do you really >want to see the problems you are supposed to be solving with optimized >routing popping up and going away again throughout the day? You hit the nail on the head. Fundametally, any route optimization technique that tries to treat an aggregate of the network as a blob which can be measured will suffer the same type of problems as an IP over ATM network. There will always be a hidden layer of complexity that will affect your traffic flow and which you cannot influence. For instance, if you look at a graph of point-to-point latency over a pure IP network it will usually be nearly flat with the occasional minor blip caused by a packet being buffered somewhere along the path. But look at the same graph for a path that includes an ATM network in the middle and it will be jumping all over the place, and sometimes you will even see wild oscillations with a regular frequency. The IP layer can do nothing about this but suffer. The same thing will happen with any measurement system that tries to classify a path through someone else's AS. You have no control over what happens in that AS and, more importantly, you have no control over the peering points bewteen ASes. Your measurements are as meaningless as measurements of an IP over ATM network. --Michael Dillon

2 1

RE: Kourou (French Guiana) seacable problem since last week, France telecom
by juan.bontje＠bt.com 27 Jan '04

27 Jan '04

Eric thanks for links information wasn't up to date as they're saying it's an satelitelink who's down, 'owned' (?) by france telecom JC -----Original Message----- From: Eric Kuhnke [mailto:eric@fnordsystems.com] Sent: Tuesday, January 27, 2004 11:07 AM To: Bontje,JC,Juan,IVYF41 C Subject: Re: Kourou (French Guiana) seacable problem since last week, France telecom Are you using capacity on the MAYA-1 or ARCOS cables? https://www.maya-1.com/stations.jsp http://www.nwncable.com/arcos_project/index.htm juan.bontje(a)bt.com wrote: > > Hi > > Anyone aware of an sea cable problem between kourou (French Guiana) and Europe? (France?), since 21jan04 > Unfortunate don't have more sufficient information besides this. > > > TIA > > JC > > > >

1 0

Re: Outbound Route Optimization
by Michael.Dillon＠radianz.com 27 Jan '04

27 Jan '04

>I am going to have to call bullshit on the MPLS fast reroute thing >there Wayne. The canonical counterexample is Sprint. To be sure, Sprint and Ebone have shown that it is possible to run a very high quality (low jitter) pure IP network, but... >Excellent engineering and ops folks top the list, followed closely >by sufficient capacity, This poses a bit of a problem. If we accept that these two things are absolutely necessary in order to run a pure IP network, i.e. no MPLS and no ATM or frame at layer 2, then that leaves out most of the world. By definition, excellent engineering and ops folks are the top minority in their field. If we assume that 10% of engineering and ops folks are "excellent", that means that 90% of network operators are unable to play this game. Also, not everyone has a facilities-based network where they can afford "sufficient" capacity. And last but not least, this whole discussion was about diversity and resilience. I would not be happy to see a network ecosystem in which every network was designed and run like Sprint's network. There is a place for MPLS and in the end, it may even prevail because of its ability to handle multiple best paths and to do fast reroute. The jury is still out on that. --Michael Dillon

1 0

Cisco 7600
by Timothy Brown 27 Jan '04

27 Jan '04

I'm aware the Cisco 7600 series is really just an evolution/different way of orienting the chassis of the Catalyst 6500 line. I'm interested in talking to those of you who are doing production tasks in the backbone or core with the 7600, particularly if you've compared it to vendor J or can comment at length on MPLS, VRF, and uRPF features in the device. Please reply off-list. No sales droids please, this is a technical discussion. Tim

3 2

RE: in case nobody else noticed it, there was a mail worm released today
by Timo Janhunen 27 Jan '04

27 Jan '04

This lovely little worm will start beating on the door at www.sco.com come Feb 1/04. Interesting huh? At 09:01 PM 26/01/2004 -0500, Wojtek Zlobicki wrote: >The worm is being talked about on news.com and all the major virus vendors >already have advisories on their websites. The worm in my case masqueraded >as a Mailer Daemon bounce. Source email address appeared to be valid and >matching a domain of a website I visited recently (but have not for a long >time). Anyone know the worm generates the sending domain. > >-----Original Message----- >From: owner-nanog(a)merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Paul >Vixie >Sent: Monday, January 26, 2004 8:52 PM >To: nanog(a)merit.edu >Subject: in case nobody else noticed it, there was a mail worm released >today > > >my copies (500 or so, before i filtered) are in a ~7MB gzip'd mailbox file >called http://sa.vix.com/~vixie/mailworm.mbox.gz (plz don't fetch that >unless you need it for comparison or analysis). there's a high degree of >splay in the smtp/tcp peer address, and the sender is prepared to try backup >MX's if the primary rejects it, though it appears to try the MX's in >priority order.

2 1

Re: Any 1U - 2U Ethernet switches that can handle 4K VLANs?
by sthaug＠nethelp.no 27 Jan '04

27 Jan '04

> > 3550 runs IOS. > > this is a benefit, especially in a switch? If your whole support organization is geared towards IOS, and unable to learn other CLIs, it may well be. Fortunately, not all support organizations are like that :-) Steinar Haug, Nethelp consulting, sthaug(a)nethelp.no

2 1

Re: in case nobody else ...
by J. Oquendo 26 Jan '04

26 Jan '04

> They rate of it is quite surprising. By the description, the trick / > method of infection does not seem all that different than past worms > viri. Makes me wonder how many people in a room would reach into their > purse/pocket on hearing, "Wallet inspector" Try and comprehend the typical home user, with no experience reading what appears to be an email from a friend or a relative. It happens. I had a friend who sent me a virus (unknowingly of course), that went to three different accounts that fall into the same mutt directory. When I inspected it, I gave the friend a call and notified them of the virus, and according to them, they only thing they received was a weird message from someone they knew. This was a fairly smart person, albeit comp illiterate. Someone working in the field (comp/networking) is almost always going to point out a flaw with someone not knowing, but the majority of those who get infected don't even know they're infected. Who do you blame them? I blame those whose OS coding is (excuse the term) crappy (security wise) in the sense it would allow 1) viruses to replicate as such, secondly I do put some blame on the provider for not filtering outbound data (silly pseudo spoofing). Just my two cents which obviously have declined with the economy =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+ Quis custodiet ipsos custodes? - Juvenal J. Oquendo GPG Key ID 0x51F9D78D Fingerprint 2A48 BA18 1851 4C99 CA22 0619 DB63 F2F7 51F9 D78D http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x51F9D78D sil @ politrix . org http://www.politrix.org sil @ infiltrated . net http://www.infiltrated.net

1 0

Re: Outbound Route Optimization.
by Scott McGrath 26 Jan '04

26 Jan '04

This was one of the pipe dreams that RSVP was _supposed_ to solve in that you could set up a end to end path with precisely specified characteristics. problem is _all_ the devices in the path need to support RSVP. Now the snake oil salesmen are coming out with boxes which purport to monitor the all paths on the internet and will indvidually select the best path for your flow. The racket will be deafening when all these boxes start running scripted ICMP sweeps to find the "best path". The solution is simple buy adequate pipes and possibly partner with a content delivery network who peers with _all_ the major carriers so that your traffic will not need to transit the major public peering points. Scott C. McGrath

3 2

Re: Any 1U - 2U Ethernet switches that can handle 4K VLANs?
by sthaug＠nethelp.no 26 Jan '04

26 Jan '04

> Both the ISL _and_ the Dotq headers are stripped off at the trunk > interface so they _both_ change the packet size but neither alters the > payload. Obviously. But the fact that ISL adds 26 bytes more than 802.1q means that multiple levels of ISL encapsulation is somewhat less practical than multiple levels of 802.1q tags. Some of us *need* those multiple levels of 802.1q tags. Steinar Haug, Nethelp consulting, sthaug(a)nethelp.no

1 0