Correct Answer : Session and Presentation layer
Explanation : The only difference between OSI model and TCP/IP model is that the functions of Presentation and Session layer in the OSI model are handled by the transport layer itself in TCP/IP. OSI is a generalized model and TCP/IP is an application specific model.
Correct Answer : DUAL
Explanation : EIGRP uses the DUAL algorithm for finding shortest path. DUAL stands for diffusing update algorithm and it is used to prevent routing loops by recalculating routes globally.
Correct Answer : 170
Explanation : Routers use the metric of administrative distance to select the best path when there are different routes to the same destination from two different routing protocols as it is a measure of reliability of routing protocols. Administrative distance for external EIGRP is 170.
Correct Answer : IP default network
Explanation : IP default network command is used to find the default gateway in Cisco router. If the router finds routes to the node, it considers the routes to that node for installation as the gateway to it.