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Re: Does Anyone Care?

  • From: Brian Dickson
  • Date: Fri Feb 11 12:41:09 2000

>  But why would the interface always transmit broadcasts to the FDDI
>  interface in Spokane and show excessive latency at anytime of the day
>  that you try to connect/send an echo reply at it.

A) Because *multicast*, when sent on a *broadcast* media like FDDI, is
sent as *broadcast* packets (to avoid replication);
B) Because multicast is very VIP2 CPU-intensive, doing all kinds of funky
things - we see that on very low utilization, there is high CPU. This in
turn shows up as latency *to* the router, but not *through* the router
(different switching paths).

Basically, this is normal, and ~5Mbps is about right for this traffic.

>  On Fri, 11 Feb 2000, Bjorn Carlsson wrote:
>  
>  > Hi,
>  > 
>  > Not sure I follow. schnell.ebone.net is actually an interface of Sprint
>  > icm-bb1-pen which connects to a FDDI ring in Pennsauken built for multicast.
>  > The name/address (schnell.ebone.net) is there for historial reasons and
>  > should be changed to something-else.icp.net.
>  > 
>  > As for directed broadcast it is long since turned off on all EBONE
>  > routers.
>  > 
>  > --BC
>  > 

--
Brian Dickson,                                    Email: [email protected]
Director, Backbone Engineering                    Tel  : +1 703 755 2056
Teleglobe Communications Corp.,                   Fax  : +1 703 755 2648
Rm 3214, 11480 Commerce Park Drive,               Cell : +1 703 851 9053
Reston, Virginia, USA, 20191                      http://www.teleglobe.com