On Wed, 18 Aug 1999, Dan Hollis wrote:
> On Wed, 18 Aug 1999, Robert G. Fisher wrote:
> > 3) My knowledge of the PC architecture is probably not the highest on
> > the list -- assuming a 100 MHz bus with 100Mhz SDRAM slots -- are
> > there any concerns on the actual bus performance?
>
> Not really, most embedded routers are much slower. Eg most ciscos until
> you get into the 7xxx range. If a cisco 3640 can handle HSSI then so can a
> PC.
Correct, but you do have to realise that the limitation is the PCI bus,
and not the memory bus, 33MHz. Also keeping (I know console mode is
minimal) the video off of the PCI and ISA busses should help speed
slightly (AGP is part of the north bridge of most chipsets, the south
bridge (ISA, etc) is actualy located on the PCI bus as a device).
33MHz, 32Bits = aproximatly 130Mbytes/sec of bandwidth.
subtract about 30Mbytes for Overhead, and divide by two (Data going in and
out), and you get 50Mbytes/sec of useable bandwidth. That is
400Mbits/sec, or almost the speed of 10 DS3 lines, or 4 100Mbit full
duplex network cards.
The cisco 7xxx series is mostly impliment in hardware (I think), and is
not a "software" router. Most lower end routers are software routers,
and the cpus/busses they use are not even close to the speed a modern sub
800 pc.
> -Dan > > -
> To unsubscribe from this list: send the line "unsubscribe linux-net" in
> the body of a message to [EMAIL PROTECTED]
>
Harry
-
To unsubscribe from this list: send the line "unsubscribe linux-net" in
the body of a message to [EMAIL PROTECTED]
