I don't have a lab to try this, but is the following possible? 3 token ring switches are connected via ISL. The scenario would be to use 1 ring number for ease. In an undistributed TrCRF setup, ports belonging to a TrCRF can only be on the same physical switch. DRiP does not allow the TrCRF port assignments to go to another physical switch to protect the network from loops.
If switch A has TrCRF #40 with a defined ring number #5, can one create on switch B a TrCRF #41 with the same defined ring number #5 and switch C a TrCRF #42 also ring #5? I assume each TrCRF will be assigned a different TrBRF with different bridge numbers. I see this as possible since I believe DRiP looks at the TrCRF/VLAN number, not ring number.
Would a separate physical bridge be required to join all 3 TrBRFs somehow to create this 1 big token ring #5?