Slightly O.T. PHP app to collect & maintain images on linux box

[MLH]

I have an AMP application running on linux server that collects,
maintains and serves up image files to web clients. On my LAN
(in fact, on the same subnet) I have both the linux box and windoze
clients. The window$ boxes are staffed by persons who sometimes
email the image files stored on the linux box to various recipients.

For simplicity, lets call my linux box L and my windoze box W.
Both are nodes on the LAN. Here are the knowns:

1) L has SMTP mail service on it
2) W has outlook express mail client s'ware configured to use
POP & SMTP services on L
3) L has a 50K bitmap graphic file on it that I want to include
as an attachment to an eMail I am creating on W.
4) The file system in which the bitmap graphic is stored looks
like a directory to my windoze box and is seen as z:\ by W.

So my windoze users just type the full path & filespec as follows
z:\mydir\mybitm ap.jpg
into outlook express' ATTACH: field and VOILA - there she goes.

QUESTION: When they click SEND, does the 50K graphic move across
the LAN from L to W, become attached to the eMail, then move again
from W to L and finally out the SMTP gateway?

My gut feeling is NO, it does not. Short of using a protocol analyzer
to snoop the wire, can any of you suggest a technique that will
proove my hypothesis right or wrong?

Normally, I wouldn't give this topic a second thought. But now, every
two days, I have 1000 of these transmissions and the rate is climbing.
It may become a source of congestion at a future point in time.

[Colin McKinnon]

Re: Slightly O.T. PHP app to collect & maintain images on linux box

MLH wrote:
[color=blue]
> 1) L has SMTP mail service on it
> 2) W has outlook express mail client s'ware configured to use
> POP & SMTP services on L
> 3) L has a 50K bitmap graphic file on it that I want to include
> as an attachment to an eMail I am creating on W.
> 4) The file system in which the bitmap graphic is stored looks
> like a directory to my windoze box and is seen as z:\ by W.
>
> So my windoze users just type the full path & filespec as follows
> z:\mydir\mybitm ap.jpg
> into outlook express' ATTACH: field and VOILA - there she goes.
>
> QUESTION: When they click SEND, does the 50K graphic move across
> the LAN from L to W, become attached to the eMail, then move again
> from W to L and finally out the SMTP gateway?
>[/color]

Yes. As for as <email program> on W is concerned, it's just attaching a file
to an email - how should it know what's a local drive & what's not. Of
course, because it's Microsoft, you need to be careful you don't attach a
link to the file (which wouldn't be derefenced until opened by another
Microsoft box...which will look in *its* Z drive for the file).

C.

[MLH]

Re: Slightly O.T. PHP app to collect &amp; maintain images on linux box

<snip>
[color=blue]
>
>Yes. As for as <email program> on W is concerned, it's just attaching a file
>to an email - how should it know what's a local drive & what's not. Of
>course, because it's Microsoft, you need to be careful you don't attach a
>link to the file (which wouldn't be derefenced until opened by another
>Microsoft box...which will look in *its* Z drive for the file).
>
>C.[/color]

Well, if you're right, I better store the image files on the W box.
I don't want them crossing the wire twice when I eMail them.
If stored on the W box, they'll only cross the wire once on their
way to the mail gateway. Of course, they'll cross it AGAIN on
their way OUT.