Note that the Supervisor 2 contains a blocking architecture internally, meaning congestion is possible in certain configurations internally on the Supervisor.
The Supervisor 1 is non-blocking, because it contains only a single 24-Gbps non-blocking switching engine that provides each of the 2-Gbps traces to module 2 and module 3 in the Catalyst 4003.
There are three seperate switching engines (SEs) exist (each provide 24-Gbps internal non-blocking forwarding bandwidth), with each providing a 2-Gbps full-duplex trace to each module in the chassis (providing a total of 3 * 2-Gbps or 6-Gbps full-duplex bandwidth to each module).
Although each SE is non-blocking internally, a single 1-Gbps full-duplex connection interconnects the switching engines, which potentially causes blocking (congestion) on the interconnections between each SE if devices attached to one switching engine are communicating with devices attached to another switching engine.
The line cards are only oversubscribed in cases of 48 ports or 24 ports but that term isnt used to describe blocking or non blocking.
HTH
Hoogen
Do rate if this Helps :) More importantly these informations are available on the CCNP switching guide.
