[c-nsp] Receiving out of order packets in SPAN session on Catalyst 3750X

[Chris Marget]

I've seen enough oddball discrepancies on port mirror functions of various
platforms (including Cat3K) over the years to conclude that SPAN et al. are
adequate for diagnosing application issues, but not for performance issues.

Non-aggregator taps are the best way to approach those problems which
require investigation into sub-millisecond timing issues, packet loss,
performance, etc...

/chris