DCQCN Specification
RFC 3168 defines the specifications for the addition of Explicit Congestion Notification (ECN) to IP.
- Defines congestion signal.
- Redefines ToS byte as 6-bit DSCP field + 2-bit ECN field, where the 2-bit ECN field can have the following values:
- 00: non ECN-capable transport
- 01: ECT(1) (ECN-Capable Transport(1))
- 10: ECT(0) (ECN-Capable Transport(0))
- 11: CE (Congestion Experienced) (the marking)