+as an IPv6 address (e.g. \fB2001:db8:3c4d:1::/ffff:ffff:ffff:ffff::\fR)
+or a CIDR block (e.g. \fB2001:db8:3c4d:1::/64\fR). Open vSwitch 1.8
+and later support arbitrary masks; earlier versions support only CIDR
+masks, that is, CIDR block and IPv6 addresses that are equivalent to
+CIDR blocks.