HP-UX IPv6 Transport Administrator's Guide for TOUR 2.0 (April 2004, rev 2)

Features Overview
IPv6 Transport (bundled as part of TOUR 2.0)
Chapter 1 5
RFC 2473 - Packet Tunneling in IPv6
RFC 2893 - Transition Mechanisms for IPv6 Hosts and Routers
RFC 3056 - Connection of IPv6 Domains via IPv4 Clouds
IMPORTANT As a result of supporting RFC 2893, tunnel configuration on HP-UX
11i v2 IPv6 bundled as part of TOUR 2.0, requires specific changes
from tunnel configurations on base (default) HP-UX 11i v2. For
detailed information, including specific configuration instructions,
refer to relevant sections of Chapter 3, “Configuration,” of this guide.
SAM has not been enhanced to support the tunneling enhancements
available with TOUR 2.0. TOUR 2.0 tunneling configuration must be
done by editing the /etc/rc.config.d/netconf-ipv6 file or by
using the ifconfig command.
— Configured tunneling is point-to-point with addresses
assigned to tunnel endpoints: In conformance with RFC 2893
(which obsoletes RFC 1933) configured tunnels are
pseudo-interfaces with associated addresses. Previously, when
conforming to RFC 1933, tunnels were implemented using
special routing entries. The RFC 1933 implementation did not
allow addresses to be associated with tunnels and hence, routing
protocol daemons were not able to operate over tunnels. To
overcome this problem, RFC 2893 specifies tunnels as IPv6
interfaces and requires them to be configured with at least (on
primary interfaces) link-local addresses.
As a result, the process for configuring tunnels using the
ifconfig and route commands and the
/etc/rc.config.d/netconf-ipv6 file is different than it was in
base (default) HP-UX 11i v2.
— HP-UX server can be configured as a router in a
point-to-point configured tunnel: You can configure
tunneling between the following network nodes: host->router;
host->host; router-> host; and router->router. In TOUR 2.0, the
HP-UX server can perform the role of the router in the tunnel
configuration. Prior to TOUR 2.0 (in TOUR 1.0 for HP-UX 11i v1
and in base (default) HP-UX 11i v2), the HP-UX server could
only perform the host role.