Average Ethernet packet length

> Hi,
>
> A recent thread suggested something interesting - an average Ethernet/IP
> packet length of 500 bytes.  Has there been any work done in the area of
> finding average packet lengths, bandwidth usage, etc. of typical (read:
> unknown) networks?  Are there any "rules of thumb" values that are
> typically used?
>
> Thanks,
>
> Tim Behne
> Signal Processing Engineer
> Tadiran Microwave Networks
> 1000 Greenbriar, Ste 100A
> Stafford, Texas 77477
> timothyb(_at_)microwavenetworks(_dot_)com