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

Features Overview

IPv6 Transport (bundled as part of TOUR 2.0)

Chapter 1 5

• IP6-in-IP6 and IP-in-IP6 Support: Starting with TOUR 2.0, two

new tunneling types are supported, IP6-in-IP6 and IP-in-IP6.

IP6-in-IP6 tunnel conﬁguration allows transmission of IPv6 packets

encapsulated in an IPv6 header. IP-in-IP6 tunnel conﬁguration

allows transmission of IPv4 packets encapsulated in an IPv6 header.

IP6-in-IP tunnel conﬁguration allows transmission of IPv6 packets

encapsulated in an IPv4 header. IP6-in-IP represents the tunneling

scenario where isolated IPv6 domains are communicating across

IPv4 networks. IP6-in-IP tunneling is not new in TOUR 2.0, it has

been supported in TOUR 1.0 and IPv6NCF11i.

• Automatic Tunneling using IPv4-compatible addresses is no

longer supported: Automatic Tunneling using the special IPv6

address type known as “IPv4-compatible address”, is no longer

supported with TOUR 2.0. The IETF is in the process of deprecating

this mechanism in favor of the generic automatic tunneling

mechanism known as “6to4.”

HP-UX 11i v1 IPv6 Transport Features Available since

TOUR 1.0

Since TOUR 1.0, the following IPv6 transport features have been

available:

• Host MLD Support: The host part of Multicast Listener Discovery

(MLD) protocol for IPv6 based on RFC 2710 “Multicast Listener

Discovery (MLD) for IPv6”, is supported. MLD is automatically

enabled when an IPv6 interface is initialized. The Management

Information Base for MLD, based on RFC 3019, is also supported.

RFC 2710 speciﬁes the protocol used by an IPv6 router to discover

the presence of multicast listeners (that is, nodes wishing to receive

multicast packets) on its directly attached links, and to discover

speciﬁcally, which multicast addresses are of interest to those

neighboring nodes. This protocol is referred to as Multicast Listener

Discovery or MLD. MLD is derived from version 2 of IPv4’s Internet

Group Management Protocol, IGMPv2. One important difference to

note is that MLD uses ICMPv6 (IP Protocol 58) message types,

rather than IGMP (IP Protocol 2) message types.

For more MLD information refer to RFC 2710, “Multicast Listener

Discovery (MLD) for IPv6”.