Book Image

Openswan: Building and Integrating Virtual Private Networks

By : Ken Bantoft, Paul Wouters
Book Image

Openswan: Building and Integrating Virtual Private Networks

By: Ken Bantoft, Paul Wouters

Overview of this book

<p>With the widespread use of wireless and the integration of VPN capabilities in most modern laptops, PDA's and mobile phones, there is a growing desire for encrypting more and more communications to prevent eavesdropping. Can you trust the coffee shop's wireless network? Is your neighbor watching your wireless? Or are your competitors perhaps engaged in industrial espionage? Do you need to send information back to your office while on the road or on board a ship? Or do you just want to securely access your MP3's at home? IPsec is the industry standard for encrypted communication, and Openswan is the de-facto implementation of IPsec for Linux.</p> <p>Whether you are just connecting your home DSL connection with your laptop when you're on the road to access your files at home, or you are building an industry size, military strength VPN infrastructure for a medium to very large organization, this book will assist you in setting up Openswan to suit those needs.</p> <p>The topics discussed range from designing, to building, to configuring Openswan as the VPN gateway to deploy IPsec using Openswan. It not only for Linux clients, but also the more commonly used Operating Systems such as Microsoft Windows and MacOSX. Furthermore it discusses common interoperability examples for third party vendors, such as Cisco, Checkpoint, Netscreen and other common IPsec vendors.</p> <p>The authors bring you first hand information, as they are the official developers of the Openswan code. They have included the latest developments and upcoming issues. With experience in answering questions on a daily basis on the mailing lists since the creation of Openswan, the authors are by far the most experienced in a wide range of successful and not so successful uses of Openswan by people worldwide.</p>
Table of Contents (22 chapters)
Building and Integrating Virtual Private Networks with Openswan
Credits
About the Authors
Acknowledgements
About the Reviewers
Preface

OE in a Nutshell


Opportunistic Encryption is a means of initiating IPsec tunnels to remote hosts by publishing and retrieving public keys from the DNS. We publish our own public key, and the remote server publishes its key, and then both servers can obtain the other's public key and set up an IPsec tunnel. No other pre-arrangement is necessary. This is a symmetrical process, and any host can initiate OE to another host. They are equal peers. However, for simplicity, we will sometimes talk about the server and the client. The intended meaning is that the client initiates, and the server responds.

If we use DNS to store our public keys, this will protect us against all passive attacks. If on the other hand DNSSEC is used, we are also protected against active attacks. The verification of DNSSEC records is not done by Openswan itself, but by the resolver library, which is called through a helper application, lwdnsq. Currently, BIND-9 is the only resolver that supports DNSSEC.

Note

To enable DNSSEC...