6This is the definitive guide to using OSPF and IS-IS protocols in large-scale IP enterprise, carrier, and service provider networks. Well-known network designer Jeff Doyle draws on his consulting experience, offering realistic advice and straight answers on every aspect of working with link-state protocols - from scalability, reliability, and security to area design and database synchronization. This book is organized to help network engineers and architects compare OSPF and IS-IS. One feature at a time, Doyle first demonstrates how a topic or feature is implemented in OSPF, and then walks through a similar implementation using IS-IS. Professionals who are relatively new to large-scale networking will welcome his practical introduction to the concepts, goals, and history of link state protocols.