EcnCodePoint# Added in version 2.88. class EcnCodePoint# Possible values of Explicit Congestion Notification code points. These appear in TOS (IPv4) or TCLASS (IPv6) packet headers and are described in RFC 3168. Fields# class EcnCodePoint ECT_0# The type of the None singleton. ECT_1# The type of the None singleton. ECT_CE# The type of the None singleton. NO_ECN# The type of the None singleton.