The Cisco NCS 4016 system supports four fabric line cards operating in a 3 + 1 redundant configuration. Each fabric card supports equally distributed connectivity across all 16 line cards. The fabric card is managed directly by the centralized route processor. The fabric is considered agnostic because it switches cells of variable sizes without knowledge of the protocol being transported, whether OTN or Ethernet. Each NCS 4016 line card is connected to all four fabric cards, one of which is redundant, allowing for full operation with three functional planes.