Fast enough to handle an OC-3 on the upstream side?

[Greg]

On Monday 23 July 2001 r, you wrote:
> Ok, I have to ask. Does anyone have a similar setup, or can anyone tell
> me, if a dual P2-450 system, with 256 MB of RAM, running Linux 2.4 and
> Squid, with a gigabit fiber card on the interior side and 100 Mbps UTP
> card on the exterior side, will be fast enough to handle NATing our
> network if we get an OC-3 (~45 Mbps)? I want to make sure the box will
> continue to have enough horsepower, as we may soon be jumping to an OC-3
> from a T-1 (The state says this, anyway - we'll see what happens. If we
> upgrade, no one is gonna complain. :), and no one likes complaining users
> or poorly-used connections, right? Right? :)
>
> Derrik Pates      |   Sysadmin, Douglas School   |    #linuxOS on EFnet
> dpates@dsdk12.net |     District (dsdk12.net)    |    #linuxOS on OPN

OK well OC-3 == 155.52 mbps
line rate in packets is 302734 per second
PCI Bus on an Desktop pci-32 Intel based system is 33Megabytes /s
155.52 mbps == 19.375 Megabytes / s

Now in theory this looks good .. however these calculations are just about
having a flow of traffic pass through the PCI Bus, and do not include the
overhead of reading the packets off the device (btw you have a pci32 GE card
?) and then applying any routing or firewalling rules to them.  If it was up
to me I would prolly go with a heaftier board / cpu.. Tyan has a serious
motherboard that they are going to be releasing very soon .. its a Dual
Athalon MP (meant to run their new 1.8ghz mp chip's with 1MB L2 cache).
On top of that it has 5 PCI-64 slots running at 66mhz and 2 onboard 3C920
10/100 lan ports that use an ASIC to communicate with the CPU's directly.
On top of that what is unique to this mobo is that each CPU has its own
independant Front side bus unlike most smp mobo's that use a shared bus.
This mobo also has intergrated dual channel adaptec ultra scsi 3 160
controller, udma 100 port and even a QLogic FiberChannel port on it and
supports up to 4GB of PC2100 DDR ram.  If you really want to support OC-3 I
think you might want to adjust the jock strap of your linux-router a tad.


--
Lamp Post Networks - http://www.lamp-post.net