Gary,


I am not a network specialist either, but you may want to read this http://www.miislita.com/internet-engineering/ip-packet-fragmentation-tutorial.pdf

Look at
2 MTU Values
3 IP Fragmentation


Basically a MTU is the largest packet that can be sent over the wire without fragmentation. A typical MTU value is 1500 bytes.
[ The MTU value of my network controller is 1500 as well - just had a look]


If you want to send a larger packet, you have to use fragmentation which should not be a problem

Each workstation listens to the traffic and picks the packets meant for that workstation. Only one station can send at a time and when a transmission is busy no one will start transmitting


TCP/IP is a collision detect protocol.
This means that when a workstation transmits a packet it listens to the traffic. When two stations transmit at the same time, they 'hear' another one was sending at the same time.
In that case, they stop transmission, wait for a random time until the network is quiescent again.

With a lot of traffic, collisions are more likely and that will make the network even slower


No one says that your application is the cause of the issues - but it may - it depends on what you do

>I have a client with a large network 25+ workstations, running a vertical market application.
>
>They are having speed issues with their network - not just my application, but general speed.
>
>Their network specialist have advised;
>
>

>"We have installed WireShark on a workstation and on the server to try and find the cause of the problem.  It was noted that there are a lot of ‘Fragmented Packets’ going between the workstation and the server.
>
>We isolated the source of the ‘Fragmented Packets’ by excluding all networked devices and creating a restricted network consisting of only the broadband router, the server and the workstation connected via a Gigabyte switch.  Initially there was no ‘Fragmented Packets’, however, as soon as <VFP application> was run the ‘Fragmented Packets’ started again.
>
>It seems clear to us that there is a problem with the way  <VFP application>  is communicating with the network and therefore we need to work together to try and resolve the problem."
>

>
>I am not a network specialist, does anyone know how VFP woudl cause fragmented packages and why this would be an issue?
>
>Is there anything I could do to resolve/change this?
>
>Gary.