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

Openswan Startup Time


The length of time the script-based system takes to read ipsec.conf can become excessive past about 100 tunnels. The following graph shows the speed of the shell/awk-based parsing system:

As can be seen from this benchmark, this is far from ideal for large-scale deployment on concentrator machines. The reason for the poor performance with a large number of tunnels is due to the startup scripts. Openswan will only start the tunnels sequentially. Currently, there are two solutions for avoiding this connection loading problem:

  1. Configure all of your tunnels as auto=ignore, start Openswan, and then use a script, similar to that used in the Standard Naming Convention section above, to run through ipsec.conf executing ipsec auto –add $conn to load each connection. These connections are then loaded in the background, resulting in all connections being loaded in parallel, greatly reducing the start-up time.

  2. Use the new C configuration parser written by Arkoon Networks—ipsec starter...