Momentary transfer rate drops

[Bigbird999]

Hi
I have a 10/100 wired LAN that has worked well for many years. Among other things, I use it to stream large mpeg 2 video files (4 GB/hr) from a PVR media server to a client computer on the LAN. This requires a transfer rate of about 1.4 MB/sec over the LAN. Lately, I have experienced choppy playback of these files and when I checked with perfmon, I find that the streaming rate drops to almost zero every 20 secs or so (see attached screen shot).

When I copy one of these large files to my client PC it transfers at 8 - 9 MB/sec but still exhibits the same behaviour (momentary rate drops). I understand this to be at the upper end of the transfer rate I can expect from a 100 Mb network. My problem is just these instantaneous drops while streaming.

I have tried researching this but the terms are so general that I can't describe my problem to get relavent results.

So the question is "Where do I start to troubleshoot this issue?" Is it one of my NICs or one of my DLink routers or switches? Could it be caused by a driver issue? I just don't know where to start.

Thanks in advance.

BB

[johnwill]

I think I'd try doing some packet sniffing on the network to see what is happening. www.ethereal.com is a good free packet sniffer.