Foreword

Network security is at a critical juncture where no single technology can solve the problem in silos. Hundreds of millions of dollars are being spent in reactively solving the virus, worms, malware problem and the rapid propagation of these vile threats. Recognizing this, Cisco has modeled the Self-Defending Network (SDN) similar to the way our bodies protect us and deal with diseases.

The SDN has several protective and integrated layers—VPNs, firewalls, intrusion prevention, and anomaly mitigation. When combined with advanced virtualization, deeper packet intelligence, and behavioral linkages with end systems, the SDN is able to proactively prevent dangerous elements from causing havoc on networks. But akin to the human body, no network can completely stop all bad things from entering. People need to eat, drink, and breathe, and networks need to process and deliver information from a wide variety of external sources. With this in mind, Cisco is constructing SDN to work at or near capacity even when invaded by detrimental entities, just as the human body can keep on functioning even when it has an infection.

This book offers deep insight into one of Cisco's flagship and recently introduced products, the Adaptive Security Appliance, ASA 5500. ASA exemplifies the importance of integration, collaboration, and adaptation to different threat patterns in security. It is one of the industry's first all-in-one network security platforms, focused on uncompromised performance and security.

The authors of this book, Jazib Frahim and Omar Santos, have intimate knowledge of security as well as internetworking. Together they have about two decades of network security expertise and have been strong advocates of thoughtful security practices and designs for Cisco. I have found this book really highlights the practical aspects needed for building real-world security. It offers the insider's guidance needed to plan, implement, configure, and troubleshoot the Cisco ASA in customer environments and demonstrates the potential and power of SDNs. I hope you enjoy the insights of this book as much as I and come to appreciate the ground-breaking security pioneered by Cisco over the past few years.

Jayshree Ullal

Senior Vice President, Security Technology Group

October 2005