the six most significant bits of the field (the DSCP bits).
.IP
Requires OpenFlow 1.1 or later.
+.
+.IP \fBmod_nw_ttl\fB:\fIttl\fR
+Sets the IPv4 TTL or IPv6 hop limit field to \fIttl\fR, which is specified as
+a decimal number between 0 and 255, inclusive. Switch behavior when setting
+\fIttl\fR to zero is not well specified, though.
+.IP
+Requires OpenFlow 1.1 or later.
.RE
.IP
The following actions are Nicira vendor extensions that, as of this writing, are
.IQ
\fBmod_nw_ecn\fR
.IQ
+\fBmod_nw_ttl\fR
+.IQ
\fBmod_tp_dst\fR
.IQ
\fBmod_tp_src\fR