This chapter covers the following exam topics:
1.0 Network Fundamentals
1.2 Compare and contrast TCP and UDP protocols
4.0 Infrastructure Services
4.1 Describe DNS lookup operation
The CCENT and CCNA Routing and Switching exams focus mostly on functions at the lower layers of TCP/IP, which define how IP networks can send IP packets from host to host using LANs and WANs. This chapter explains the basics of a few topics that receive less attention on the exams: the TCP/IP transport layer and the TCP/IP application layer. The functions of these higher layers play a big role in real TCP/IP networks, so it helps to have some basic understanding before moving into the rest of the book, where ...