CCNA Study Guide Chapter 4 Summary

This chapter began with a look at the TCP/IP protocol suite. This included a look at the protocols that make up TCP/IP and the way in which they relate to the ISO OSI model.
A look at Network layer protocols provided an overview of IP packets and addressing, the way in which ARP is used to map IP addresses to MAC addresses, as well as how ICMP provides error reporting and diagnostic information.

Examination of protocols at the Transport layer provided an overview of both TCP and UDP, including their header structures. A closer look at TCP provided insight into port numbers, how connections are defined, how they are terminated. An introduction to UDP provided perspective on how it differs from TCP as a connectionless protocol with lower overhead.

Examples of common port numbers that act as interfaces to upper-layer protocols were also examined.

A look at the TCP/IP Application layer provided an overview of some common protocols and services found at this layer.

An examination of the NetWare protocol suite began with a look at the four Ethernet encapsulation types supported by Cisco and the terms used to refer to them on Cisco routers. A look at the Network layer provided an overview of IPX addressing and packet structure. At the upper layers, a variety of protocols were covered including the connection-oriented SPX. Other protocols discussed included NCP, NetWare Shell, NetBIOS and SAP, the Service Advertising Protocol.

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