[aclug-L] Re: Ideas for Sept Aclug Meeting?

["Jonathan Hall" <flimzy@xxxxxxxxxx>]

The DPSs (or rough equivolents, depending on what type of physical
network(s) you're connecting to) in a Linux router are found on the NICs,
Modems, or other network hardware.

When routing a T line, ATM, or other such networks commonly routed with a
Cisco, or when terminating a PRI or such (as in the case with a PM3),
separate hardware handles that in Linux, too.  With the proper hardware, a
Linux box routing multple DS3s will also have practically no CPU load
unless, of course, a lot of policy routing or similar, is in place.

It may be true on some level that Cisco vs. Linux is apples-to-oranges, but
the difference is primarily in the software.  The Cisco's software is
designed *only* to handle routing.  There aren't any options for
framebuffers, webcams, or 3D sound on a Cisco (at least not to my
knowledge!).  Granted, Cisco hardware is also "fine tuned" for network
routing, that can have only so much effect.

-- Jonathan


----- Original Message -----
From: "Chris Owen" <owenc@xxxxxxxxxx>
To: <discussion@xxxxxxxxx>
Sent: Friday, September 03, 2004 5:24 PM
Subject: [aclug-L] Re: Ideas for Sept Aclug Meeting?


> On Fri, 3 Sep 2004, Jonathan Hall wrote:
>
> > An interesting side note when comparing CPUs for routers... I believe
> > many Cisco routers use 486-type CPUs (perhaps even exactly 486 CPUs...
> > Someone on this list I'm sure knows more precisely).  I do know that the
> > Portmaster 3 terminal server I used to use when I ran an ISP used a
> > 486/66 CPU, and the Portmaster 2 uses a 386/33 CPU (if memory serves).
> > And both of these machines do much more than the typical "Linux router"
> > in terms of bandwidth usage.
>
> While I certainly wouldn't argue that a low end CPU isn't completely fine
> for a home linux router, comparing the CPU in something like a Cisco
> router or a PM3 to that in a linux router is really comparing apples and
> oranges.
>
> Yes a PM3 only had a 486 in it but really the CPU in a box like that
> doesn't do much more than run the command line.  The thing is loaded with
> DSPs and other chips that do most of the real work.  Usually your linux
> router isn't going to have any of these things.
>
> A Cisco 7200 doing standard routing on several DS3s worth or traffic is
> going to have a CPU load of about nothing.  However, as soon as you start
> putting a bunch of policy routing and other things that the CPU needs to
> think about you can melt it with probably no more than a DS1's worth of
> traffic.
>
> Ironically for that reason a linux router can usually do much better than
> a Cisco when it comes to things like policy routes or NAT.  The Cisco
> boxes are just designed to offload the real work elsewhere and as soon as
> the CPU has to do much they can get in trouble fast.
>
> Chris
>
> --
>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Chris Owen                ~ Garden City (620) 275-1900 ~  Lottery (noun):
> President                 ~ Wichita     (316) 858-3000 ~    A stupidity
tax
> Hubris Communications Inc ~       www.hubris.net       ~
>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> -- This is the discussion@xxxxxxxxx list.  To unsubscribe,
> visit http://www.complete.org/cgi-bin/listargate-aclug.cgi
>
>

-- This is the discussion@xxxxxxxxx list.  To unsubscribe,
visit http://www.complete.org/cgi-bin/listargate-aclug.cgi