The "Foundation Topics" section includes discussions of BGP, PBR, route redistribution, and IP multicast protocols. The "BGP" section covers the characteristics and design of BGP. eBGP exchanges routes between autonomous systems. eBGP is commonly used between enterprises and their service providers.
The section "Route Manipulation" covers how you use PBR to change packets' destination addresses based on policies. This section also covers route summarization and redistribution of route information between routing protocols.
The section "IP Multicast Review" covers multicast protocols such as IGMP, Cisco Group Management Protocol (CGMP), and Protocol Independent Multicast (PIM).