If unsure, say N.
+config IPV6_GRE
+ tristate "IPv6: GRE tunnel"
+ select IPV6_TUNNEL
+ ---help---
+ Tunneling means encapsulating data of one protocol type within
+ another protocol and sending it over a channel that understands the
+ encapsulating protocol. This particular tunneling driver implements
+ GRE (Generic Routing Encapsulation) and at this time allows
+ encapsulating of IPv4 or IPv6 over existing IPv6 infrastructure.
+ This driver is useful if the other endpoint is a Cisco router: Cisco
+ likes GRE much better than the other Linux tunneling driver ("IP
+ tunneling" above). In addition, GRE allows multicast redistribution
+ through the tunnel.
+
+ Saying M here will produce a module called ip6_gre. If unsure, say N.
+
config IPV6_MULTIPLE_TABLES
bool "IPv6: Multiple Routing Tables"
depends on EXPERIMENTAL