This field configures an action that IOP should take against cells when traffic congestion occurs.

earlyPktDiscard(1) is treated as 'enable' for IOP version 1 since it doesn't support early packet discard feature. Early packet discard is an IOP 2 feature. In this mode, IOP either passes or discards all the cells of a packet. It passes all cells of a packet during congestion if the first cell of the packet has been passed. Cells are marked when GCRA contract is violated. This option does not apply to VBR_RT and CBR and CBR_PRS.

disable(2) is selected to disable early packet discard and partial discard feature. Cells are discarded when needed during congestion. Cells are marked when GCRA contract is violated.

partialPktDiscard(3) is an IOP 2 feature. IOP starts discarding cells--all of the remaining cells except for the last cell of the packet-when congestion occurs. When congestion ends, the first cell of a new packet is passed. Cells are marked when GCRA contract is violated. This option does not apply to VBR_RT and CBR and CBR_PRS.

The default value for IOP 1 is 'disable'. The default value is 'earlyPktDiscard' for IOP 2 if the transport type of the circuit is UBR, ABR, and VBR_NRT. 'disable' is the default VBR_RT and CBR.