Beko,
The 4096 bytes is a the maximum recommended packet size for a streaming from a single camera on Windows. The limit is enforced by Windows FireWire bus driver in software. Many cameras also enforce 4096 bytes as the maximum packet size. You may be able to allocate up to 5000 bytes over multiple cameras as long as a single camera does not exceed 4096 bytes.
On LabVIEW RT there is no maximum recommended packet size enforced by the FireWire bus driver. On the CVS and NI PXI-8252 running with LabVIEW RT you should be able to allocate up to 4900 bytes for a single cameras. Some cameras, like the
Prosilica CV Series, take advantage of this to attain faster frame rates. The bandwidth used by these cameras are about 37-38 MB/s which is very close to the 40 MB/s that the hardware is theoretically capable of.
Hope this helps,
JohannS