[ale] Huge number of PPP connections

[Russell Enderby]

I run 64 ports on a single Red Hat 5.2 box, using Cyclades boxes.  It
would be recommended to run two boxes with 64 a piece for your
solution.  You could try to slap 128 on it but it would require alot of
ram and cpu power, not to mention atleast 4 PCI or ISA slots to handle
the hardware alone.

Russell

Joe Knapka wrote:

> Hey, folks,
>
> A co-worker of mine is working on a project where he needs
> to talk to a large number (hundreds) of remote field
> devices over leased lines using PPP. He's wondering if Linux
> would be an appropriate platform for a communication server.
> The bandwidth requirements are low (probably 9600 bps
> per channel), but the comms server *can't crash* - so he's
> thinking that NT is right out. Normally we'd do this kind
> of thing with VME boards running VxWorks, but there are
> legacy/monetary issues involved here that preclude such
> a solution.
>
> I hope someone on this list can give us some pointers about
> how (and whether) to do this. It's not too different in spirit
> from running a dialup IP service, so maybe someone has done
> something similar.
>
> Specific questions are:
>
> (1) We need at least 128 channels. Is it reasonable to expect
> Linux to handle 128 PPP connections simultaneously? What
> class of machine would be required? (I believe the answer is
> "yes, a really fast one with a whole bunch of memory")
>
> (2) How to even get 128 serial ports? We know the Digi EC/X
> concentrator card will do it, but there doesn't seem to be
> a Linux driver for that particular card. Are there
> any alternatives? We might not mind adding more comms server
> machines if necessary, but we'd like to do it all on
> a single one if possible.
>
> (3) What is the magnitude of development work likely to be
> required? (I believe the answer is, "hardly any, once the
> system is configured. Probably just write a chat script to
> connect the field devices").
>
> TIA,
>
> -- Joe Knapka
> * I speak only for myself, not for these idiots:
> * The Software Monastery - "Better Software Through Divine
> * Intervention." Source-code prayer vigils available - nominal
> * donation $0.01/LOC. http://whyme.penguinpowered.com/monastery.html



--
Russell T. Enderby                                        Arris
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