The 2950 does support SPAN (Port Mirror)
monitor session 1 source interface fastethernet 0/5
monitor session 1 destination interface fastethernet 0/1
Source is the port that you want to capture data from
Destination is the port that you want the captured data to be sent to (Typically, this is the host
you use for the packet captures)
Verify the span
show monitor session 1
