HP-UX IPSec and HP-UX Mobile IPv6

Introduction

Securing Mobile IPv6 with HP-UX IPSec

You can configure HP-UX IPSec to secure Mobile IPv6 packets between a Home Agent and Mobile Node on systems that are HP-UX Mobile IPv6 Home Agents. There are four types of Mobile IPv6 packets to secure with IPSec:

1. Binding Messages between the Home Agent and Mobile Node

The Binding Messages are Binding Update and Binding

Acknowledgement messages.

2.Return Routability Messages routed through the Home Agent

The Return Routability messages routed through the Home Agent are Home Test Init and Home Test messages.

3.Prefix Discovery Messages

The Prefix Discovery Messages are ICMPv6 Mobile Prefix Solicitation and ICMPv6 Mobile Prefix Advertisement messages.

4.Payload packets routed through the Home Agent.

In Mobile IPv6 Basic Operation, payload packets between the Mobile Node and Correspondent Node are routed through the Home Agent.

Binding Messages Between the Home Agent and Mobile Node

RFC 3776 specifies that you must use ESP to secure Binding Update and Binding Acknowledgement messages between the Home Agent and Mobile Node. (See Appendix A, “RFC 3776 Mandatory Support” on page 279 for the RFC 3776 extract.)

When a Mobile Node attaches to a new network, the Mobile Node sends a Binding Update message to its Home Agent with its new Care-of Address. The Binding Update message must be protected to prevent intruders from sending Binding Update messages with false Care-of Addresses.The Home Agent sends a Binding Acknowledgement message to the Mobile Node to confirm it received the Binding Update.

The Mobile Node’s home address is not in the source or destination IP address fields in the binding messages; the source IP address in the Binding Update is the Mobile Node’s Care-of Address, and the destination IP address in the Binding Acknowledgement is the Mobile Node’s Care-of Address. However, Mobile IPv6 uses a special IPv6 header option and header—the Home Address destination option and

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Chapter 7