There are several “core” pieces currently.  Core is defined somewhat vaguely as connecting lots of devices or requiring relatively high performance: 

1.    ITD’s main switch in the DAQ room
2.    DAQ’s event builder switch in the DAQ room
3.    the starp switch on the South Platform
4.    the DAQ/TRG switch on the South Platform
5.    the Force 10 switches for the HPSS network in the DAQ room

It seems likely that any reshape will have to include those same core components, though perhaps some combinations are possible at the hardware level using VLANs or other technologies.  (combining starp and DAQ/TRG on the platform on to a single large switch, for instance)