1. 802.17c Protected Inter-Ring Connection Rafi Ram - Corrigent Systems March 2007

2. 2 PIRC Sublayer in MAC Block Diagram

3. 3 Network Diagram Stations A & B are protection group on the primary ring Station A is the “0” member and station B is the “1” member Stations C & D are protection group on the secondary ring Station C is the “0” member and station D is the “1” member

4. 4 PIRC Sublayer Logic on the Path MAC  Client if (bit 40 of the RPR DA is set) then if (PG state is “both active”) then if ((hash modulo result) != (member type)) then discard frame else if ((MAC is on secondary ring) and (RPR SA is the mate MAC addr)) discard frame else forward frame else if (PG state is “self down” or “hold-off”) then discard frame else forward frame else forward frame

5. 5 PIRC Sublayer Logic as State Table RowConditionAction 1RPR DA[40] is 0Forward 2PG state is “mate down”Forward 3PG state is “self down”Discard 4PG state is “hold-off”Discard 5This MAC is on primary ringForward 6RPR SA is equal to mate MAC addressDiscard 7-Forward