nanog mailing list archives
Re: Shim6, was: Re: filtering /48 is going to be necessary
From: Ryan Malayter <malayter () gmail com>
Date: Tue, 13 Mar 2012 04:49:39 -0700 (PDT)
On Mar 13, 2:21 am, Masataka Ohta <mo... () necom830 hpcl titech ac jp> wrote:
William Herrin wrote:When I ran the numbers a few years ago, a route had a global cost impact in the neighborhood of $8000/year. It's tough to make a case that folks who need multihoming's reliability can't afford to put that much into the system.The cost for bloated DFZ routing table is not so small and is paid by all the players, including those who use DFZ but do not multihome.Hi,http://bill.herrin.us/network/bgpcost.htmlIf you believe there's an error in my methodology, feel free to take issue with it.Your estimate on the number of routers in DFZ: somewhere between 120,000 and 180,000 with the consensus number near 150,000 is a result of high cost of routers and is inappropriate to estimate global cost of a routing table entry. Because DFZ capable routers are so expensive, the actual number of routers is so limited. If the number of routes in DFZ is, say, 100, many routers and hosts will be default free
For quite some time, a sub-$2000 PC running Linux/BSD has been able to cope with DFZ table sizes and handle enough packets per second to saturate two or more if the prevalent LAN interfaces of the day. The reason current routers in the core are so expensive is because of the 40 gigabit interfaces, custom ASICs to handle billions of PPS, esoteric features, and lack of competition. The fact that long-haul fiber is very expensive to run limits the number of DFZ routers more than anything else. Why not take a default route and simplify life when you're at the end of a single coax link? If your lucky enough to have access to fiber from multiple providers, the cost of a router which can handle a full table is not a major concern compared with your monthly recurring charges. -- RPM
Current thread:
- Re: Shim6, was: Re: filtering /48 is going to be necessary, (continued)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Geoff Huston (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary William Herrin (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Leo Bicknell (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary William Herrin (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Masataka Ohta (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary William Herrin (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Josh Hoppes (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Mark Andrews (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary William Herrin (Mar 12)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Masataka Ohta (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Ryan Malayter (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Masataka Ohta (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Owen DeLong (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Ryan Malayter (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Ryan Malayter (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Owen DeLong (Mar 13)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Valdis . Kletnieks (Mar 14)
- RE: Shim6, was: Re: filtering /48 is going to be necessary Leigh Porter (Mar 14)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Mike Andrews (Mar 14)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Robert Bonomi (Mar 14)
- Re: Shim6, was: Re: filtering /48 is going to be necessary Owen DeLong (Mar 14)