- NANOG - lists.nanog.org

Fw: Where is the edge of the Internet?
by alok 06 Nov '02

06 Nov '02

address (as per your scenario). You look up the destination in the routing table, and don't find it. So we look in RFC792 on page 5: If, according to the information in the gateway's routing tables, the network specified in the internet destination field of a datagram is unreachable, e.g., the distance to the network is infinity, the gateway may send a destination unreachable message to the internet source host of the datagram. In addition, in some networks, the gateway may be able to determine if the internet destination host is unreachable. Gateways in these networks may send destination unreachable messages to the source host when the destination host is unreachable. -------------> who does? the source is reachable.......via BGP.....its a valid internet address... And you send that to the bogus source address *HOW*? ------> how what??...it still isnt a problem for the actual traffic, the "source" network may exist on a BGP router as being advertised from another AS ......but not on the edge router from where it uplinks ......as was being discussed here Also, note the following: Another case is when a datagram must be fragmented to be forwarded by a gateway yet the Don't Fragment flag is on. In this case the gateway must discard the datagram and may return a destination unreachable message. Getting Path MTU Discovery to work is tough enough without some bozo network engineer assuming that assymetric paths with unroutable endpoint addresses will actually work. Yeah, sure - the destination *MIGHT* have a route back, but if *you* don't have a route back, things will break in subtle ways. ---------------> suggest u read the thread... we were : 1. discussing a ip spoofed attacks 2. the network/ip may exist on a BGP running router as being advertised from antoher AS/ differnet ISP.. its still present on the internet, .... but its a BGP route, not an IGP route...although that network uplinks from ur network...whats the problem? where does all this cause a problem? all ur edges will 0.0.0.0/0 to some bgp running router and the packet will get there.. ......there are enuf asymmetric networks, i can assure of of that... for one, you could simply try running a traceroute to some tracert sites from ur PC and a reverse trace from those servers to you.... ull find lots...

5 6

RE: High Processor Rates on Routers.
by Jim Deleskie 06 Nov '02

06 Nov '02

Try a show proc cpu to see what the router is doing if you really want to find out. -Jim -----Original Message----- From: internetguy205(a)hotmail.com [mailto:internetguy205@hotmail.com] Sent: Wednesday, November 06, 2002 8:22 AM To: nanog(a)merit.edu Cc: headguy(a)techies.com Subject: High Processor Rates on Routers. Ladies & Gentleman. Was wondering if it is common for processor rates on higher end Crisco boxes to race from 1 or 2 % show on the 5 second processor rate interval, to anywhere from 70 to 90 %, instanteously, then drop back down to 1 or 2 % after 10 seconds. The above mentioned scenario would happen every 30 seconds. The higher end boxes are very lightly loaded, with total traffic throughput of maybe 100 Meg, in some cases. Think that if these boxes are loaded more, to the point where the aggragated throughtput approaches a Gig, this will cause the processors to run at high levels constantly, driving the CPU rates indicators on the box for 1 & 5 minute intervals up to the values mentioned above. ( 70 to 90 % ). Higher end devices would be something like 7200, 7500, 12xxx series routers. This scenerio would be in a large ( very large network, atleast a tier 2 OR tier 1 provider )... possible rebutals to the fact that processors could race like mentioned above on lightly loaded devices of a higher end nature would be that BGP scanner is causing the problem, Telnet to the devices, show config when on the devices... So what happens to the processor rates when the devices are more heavily loaded ( 1 G aggragated throughput opposed to 100 Meg throughtput )? Will the devices work worrectly AND would a large internet be stable ? Is it also common for BGP Routing tables to be changing version every 1/2 second ? Same high end routers, lightly loaded, large Autonomous System. Thank-you for your time on this query.

1 0

Re: [High Processor Rates on Routers.]
by Joshua Smith 06 Nov '02

06 Nov '02

"internetguy205(a)hotmail.com" <internetguy205(a)hotmail.com> wrote: > > > Ladies & Gentleman. > > > Was wondering if it is common for processor rates on higher end Crisco boxes to race from 1 or 2 % show on the 5 second processor rate interval, to anywhere from 70 to 90 %, instanteously, then drop back down to 1 or 2 % after 10 seconds. > [snip....] i notice this on my 7513s - usually it occurs when i make a bgp or acl change, but i haven't been able to track it down to something more specific cheers joshua "Walk with me through the Universe, And along the way see how all of us are Connected. Feast the eyes of your Soul, On the Love that abounds. In all places at once, seemingly endless, Like your own existence." - Stephen Hawking -

1 0

Re: [RFI Pointers to technical organisation layouts]
by Joshua Smith 06 Nov '02

06 Nov '02

"Thomas Kernen" <tkernen(a)deckpoint.ch> wrote: > > > Hi, > I'm looking for the layout of the technical organisation within service providers. Charts with role definitions, related and/or > critical processes, inter-departement communications, chain of command, breakout within major units, relation between > NOC/engineering/billing/service turnup/etc, basically anything I can get my hands on. > > Note that I'm not planning a reorg, simply wanting to compare with other service providers (big and small) and how they operate > internally. > > Thomas > i too would be interested in seeing how other organizations are put together - i would appreciate being copied, and would be glad to put together a summary for the list. cheers joshua "Walk with me through the Universe, And along the way see how all of us are Connected. Feast the eyes of your Soul, On the Love that abounds. In all places at once, seemingly endless, Like your own existence." - Stephen Hawking -

1 0

RE: RFI Pointers to technical organisation layouts
by Kris Foster 06 Nov '02

06 Nov '02

> > Carrier Scale IP: Designing and Operating Internet Networks > > by P. Willis (Editor) > > Is that Pete Willis who was in BTnet Technical Services? Appears so.. > > > > This book contained various examples of BT's organization.. > > Check out the review here: [sorry Nigel :-)] > > http://www.amazon.co.uk/exec/obidos/ASIN/0852969821/qid%3D/202 > -9691701-8052621 > Didn't say the book was good :) http://www.cisco.com/warp/public/759/ipj_5-3/ipj_5-3_reviews.html Kris

1 0

RE: RFI Pointers to technical organisation layouts
by Kris Foster 06 Nov '02

06 Nov '02

> I'm looking for the layout of the technical organisation > within service providers. Charts with role definitions, related and/or > critical processes, inter-departement communications, chain > of command, breakout within major units, relation between > NOC/engineering/billing/service turnup/etc, basically > anything I can get my hands on. http://www.amazon.com/exec/obidos/tg/detail/-/0852969821/qid=1036594290/sr=8 -1/ref=sr_8_1/002-7468082-2679216?v=glance&s=books&n=507846 Carrier Scale IP: Designing and Operating Internet Networks by P. Willis (Editor) This book contained various examples of BT's organization.. Kris

2 1

RFI Pointers to technical organisation layouts
by Thomas Kernen 06 Nov '02

06 Nov '02

Hi, I'm looking for the layout of the technical organisation within service providers. Charts with role definitions, related and/or critical processes, inter-departement communications, chain of command, breakout within major units, relation between NOC/engineering/billing/service turnup/etc, basically anything I can get my hands on. Note that I'm not planning a reorg, simply wanting to compare with other service providers (big and small) and how they operate internally. Thomas

1 0

Re: Where is the edge of the Internet?
by alok 06 Nov '02

06 Nov '02

come to think of it, it certainly makes it easier in the access...everything points to that... would help if there ws a "mandatory doc"..then even those "assymetric routing" chaps would anyways put it in their access :o) -rgds alok ----- Original Message ----- From: alok <alok.dube(a)apara.com> To: Martin <marty(a)supine.com>; <nanog(a)merit.edu> Sent: Wednesday, November 06, 2002 1:15 PM Subject: Re: Where is the edge of the Internet? heard of default routes..?.... u dont always need an iBGP full mesh u cud redistribute a bit and "default route" a bit.... okie i know now...u give me a practice doc and say "bad boy" :o)... u can redistribute im sure there is nothing bad with that.......and also u will tend to summarize a lot with default routes too.... that was my point..... the other angle being "DDoS with spoofed ips".. right? those IPs care intertnet registerd ips? now no reason that if the router B runs OSPF that u may not have an entry for the source IP... it will be there either via redistribution or via iBGP if thats the way u want it.....or covered under default.... :o) what i mean by valid is this: "registered internet IP address" in this case you may have routes to the source network anyways iva iBGP or redistribution... inspite of a "DDoS" or "assymetric cases" ....or it may be a part of the "default route"..... also agreed this default route is more on the access end most guys tend to have links between BGP routers or run iBGP etc......then the same logic applies there too.... -rgds Alok ----- Original Message ----- From: Martin <marty(a)supine.com> To: alok <alok.dube(a)apara.com> Sent: Wednesday, November 06, 2002 12:36 PM Subject: Re: Where is the edge of the Internet? $author = "alok" ; > > here is the scenario > > u have a bgp A ---ospf-B - bgpC router setup > > what will u do on ospf -B ? > > coz transit traffic can flow thru it... how does router B know where to send packets transitting the network? you'd need to run iBGP on it or be redistributing routes from BGP into OSPF, otherwise router B is not going to pass packets appropriately. > but what i was trying to say to Valdis....was that u cant just "blindly" > drop packets in the core whose source doesnt have a route...for eg ospfB is > a problem in the above that's why you don't do it blindly. :) you pick a router that has it's eyes wide open (ie. has a full table) to do RPF filtering on. marty -- Can't buy what I want because it's free. Can't be what they want because I'm me. "Corduroy" - Pearl Jam

1 0

Peerings
by Petri Helenius 06 Nov '02

06 Nov '02

Is there a "standardized" depository of information where lists of which AS´s are present in which exchange(s)? RADB does not really cut it since it only lists the participants of the interconnect, not really identifying the facility. Obviously I´m aware that most IXn list their participants on a web site but I´m looking for more machine readable data. Pete

6 5

Re: Where is the edge of the Internet?
by alok 06 Nov '02

06 Nov '02

heard of default routes..?.... u dont always need an iBGP full mesh u cud redistribute a bit and "default route" a bit.... okie i know now...u give me a practice doc and say "bad boy" :o)... u can redistribute im sure there is nothing bad with that.......and also u will tend to summarize a lot with default routes too.... that was my point..... the other angle being "DDoS with spoofed ips".. right? those IPs care intertnet registerd ips? now no reason that if the router B runs OSPF that u may not have an entry for the source IP... it will be there either via redistribution or via iBGP if thats the way u want it.....or covered under default.... :o) what i mean by valid is this: "registered internet IP address" in this case you may have routes to the source network anyways iva iBGP or redistribution... inspite of a "DDoS" or "assymetric cases" ....or it may be a part of the "default route"..... also agreed this default route is more on the access end most guys tend to have links between BGP routers or run iBGP etc......then the same logic applies there too.... -rgds Alok ----- Original Message ----- From: Martin <marty(a)supine.com> To: alok <alok.dube(a)apara.com> Sent: Wednesday, November 06, 2002 12:36 PM Subject: Re: Where is the edge of the Internet? $author = "alok" ; > > here is the scenario > > u have a bgp A ---ospf-B - bgpC router setup > > what will u do on ospf -B ? > > coz transit traffic can flow thru it... how does router B know where to send packets transitting the network? you'd need to run iBGP on it or be redistributing routes from BGP into OSPF, otherwise router B is not going to pass packets appropriately. > but what i was trying to say to Valdis....was that u cant just "blindly" > drop packets in the core whose source doesnt have a route...for eg ospfB is > a problem in the above that's why you don't do it blindly. :) you pick a router that has it's eyes wide open (ie. has a full table) to do RPF filtering on. marty -- Can't buy what I want because it's free. Can't be what they want because I'm me. "Corduroy" - Pearl Jam

1 0