ccna-1 midterm exam v7.2

ccna-1 midterm exam v7.2.This consumes many more CPU cycles than the distance vector protocol approach of increasing the metric of the received routes and comparing the results to the routes already in the routing table.For example, in link-state networks, flipped routes can affect many routers, especially when they are flipped every 10.15 seconds. The advantage of distance vectoring protocols is that routers only need to do this when they receive periodic updates and consume very few router resources to process these updates.Link-state protocols use the shortest path first (SPF) algorithm to select the best path. By default, they are informed of the complete network topology by link-state updates. They send triggered updates when changes occur in the network. They take up more CPU and memory resources than distance vectoring protocols. However, they take up less network resources because they use multicast to propagate routing information and only advertise routing information that has changed. In addition, with route aggregation and hierarchical routing, link-state protocols support network scaling to great size.1424 Hybrid ProtocolsHybrid protocols combine the advantages of distance vector and link-state protocols. Hybrid protocols are typically based on distance vector protocols, but combine the features and benefits of link-state protocols. Hybrid protocols include RIPv2, EIGRP, and BGP.RIPv2 is discussed in more depth in Chapter 18, and EIGRP is covered in Chapter 20.BGP is outside the scope of this book, but is a top priority for CCNP certification.For example, Cisco EIGRP is similar to the distance vectoring protocol in its handling of routing updates, thereby reducing the CPU and memory resources consumed; however, instead of sending periodic updates like the distance vectoring protocol, EIGRP sends reliable incremental updates via multicast messages, creating a more network- and router-friendly environment oEIGRP also supports numerous other features of link-state protocols, such as VLSM and route summarization.BGP is also a hybrid protocol with many of the features of distance vectoring protocols. It is based on a standard (RFC 1772) that is the standard routing protocol used to interconnect ISPs and companies on the Internet. Unlike most other protocols that use multicast or broadcast to propagate information, BGP establishes TCP connections to neighboring peers (using port 179), and uses TCP to share connection information. _Like EIGRP and OSPF, BGP supports route summarization; the difference is that BGP is used to route traffic between autonomous systems.Given the high overhead of link-state protocols, distance vectoring protocols, such as RIP, were previously commonly used in small and medium-sized networks. with the development of hardware, distance vectoring protocols are currently less commonly used, even in small networks. The most commonly used dynamic IGP protocol is OSPF, a distant second to EIGRPo In small office/home office (SOHO) networks, static routing is the most common routing mechanism.Authentication|Standard 14.0314.3 Problems with Distance Vectoring Protocols and Their Solutions