About the Authors Silviu Angelescu is a network and software engineer, consultant and technical trainer, specialized in data networks, storage networks and virtualization. He has worked as network and software engineer, consultant and corporate trainer for more than ten years at various high-tech companies and academic institutions, such as, Network Appliance (NetApp), Computer Associates (CA), CGI, Dawson College, and the University of Montreal. Silviu also ran a consulting business for training organizations, designing, developing, and deploying scheduling software and network services. He graduated in Computer Science at the University of Montreal and is currently an engineer and trainer in the Research Triangle Park, in North Carolina, USA. Andrew Swerczek is a network engineer, computer lab instructor, and technical writer with over twenty years experience in the Information Technology fi eld. He has worked for various governmental agencies and contractors including the US Department of Defense and Wang Laboratories. Andrew has achieved many IT industry certifi cations such as CCNA, CNE, CNA, CIW, DCSNP, NACA, FCA, IBA, i-Net+, Network+, Server+, and A+. He is a graduate from the London School of Journalism, owns a small business, and currently resides in the Harz Mountains region, in Germany. Author’s Acknowledgments I would like to thank Katie Feltman, Pat O’Brien, John Edwards, and Bruce Tomlin: thanks for your hard work, support and patience. A lot of work goes into publishing and producing a book: I want to thank everyone at Wiley who worked behind the scenes to keep this project on track and make it happen. I also want to thank Andrew Swerczek for his hard work and contribution to this book: Chapters one to fi ve in Book II, Chapters one to four in Book VI, Chapters one to four in Book VII. Thanks also to Ed Tetz for his contribution: Chapters two to fi ve in Book V. Publisher’s Acknowledgments We’re proud of this book; please send us your comments at http://dummies.custhelp.com. For other comments, please contact our Customer Care Department within the U.S. at 877-762-2974, outside the U.S. at 317-572-3993, or fax 317-572-4002. Some of the people who helped bring this book to market include the following: Acquisitions, Editorial, and Media Composition Services Development Project Coordinator: Katie Crocker Project Editor: Pat O’Brien Layout and Graphics: Christin Swinford, Senior Acquisitions Editor: Katie Feltman Christine Williams Copy Editor: John Edwards Proofreaders: Jessica Kramer, Toni Settle Technical Editor: Bruce Tomlin Indexer: Broccoli Information Mgt. 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Chapter 4: Routing Information Protocol (RIP) .........................................................587 Chapter 5: Enhanced Interior Gateway Routing Protocol (EIGRP)..........................607 Chapter 6: Open Shortest Path First (OSPF) Protocol ..............................................625 Book V: Wireless Networks ....................................... 645 Chapter 1: Introducing Wireless Networks ................................................................647 Chapter 2: Wireless Local Area Network (WLAN) Security ......................................665 Chapter 3: Wireless Local Area Network (WLAN) Operation Modes ......................675 Chapter 4: Managing Cisco Wireless Local Area Networks ......................................691 Chapter 5: Confi guring Cisco Wireless Local Area Networks ..................................701 Book VI: Network Security ....................................... 715 Chapter 1: Network Security Basics ............................................................................717 Chapter 2: Introducing IP Access Lists (IP ACLs) ......................................................735 Chapter 3: Introducing Network Address Translation (NAT) ..................................763 Chapter 4: Introducing Virtual Private Networks (VPNs) .........................................785 Book VII: Wide Area Networks (WAN) ..................... 805 Chapter 1: Wide-Area Networking Basics ...................................................................807 Chapter 2: HDLC (High-Level Data Link Control) Protocol ......................................823 Chapter 3: PPP (Point-to-Point Protocol) ...................................................................831 Chapter 4: Frame Relay .................................................................................................855 Appendix A: About the CD ........................................ 881 Appendix B: Cisco CCNA Exam Preperation ................ 885 Index ...................................................................... 897