NT1210 Lab 3.1 Review

Vance Campbell
NT1210 – Intro to Networking
Lab 3.1 to 3.4
3.1

1. Why would a three-layer model of communication that has the layers physical, network, and application be insufficient to adequately describe network communication?

A. Because there is no transport or application layer.

2. What is the history of the OSI reference model? How did it come about and why was it created? Use your textbook and Internet research to support your answer.

A. It was created to standardize the way networks communicate.

3. What is the history of the TCP/IP model? Why was it created? Use your textbook and Internet research to support your answer.

A. The model was to show the standard procedures and made it so people could understand how it worked.

3.2

1. How does the abstraction of the physical layer facilitate interoperability across networks using different types of physical wires?

A. There may not be areas where wires can access, but there is always wireless capabilities.

2. The OSI model is not directly implemented in networking and often the distinction between the layers will blur in implementation. Why does it endure despite these issues? Use your textbook and Internet research to justify your answer.

A. The model helps visualize what is happening. It endures because it is a set a proven model.

3. Given the purpose of each, is it necessary to retain the top three layers of the OSI model as separate entities? Use the textbook and Internet research to justify your answer.

A. The layers are all about how the application handles data, not the network, which is what the model demonstrates. They could be combined or separated.

3.3

1. UDP is a connectionless protocol, unlike TCP, so there is no feedback on whether a packet was received. When would this type of protocol be useful and what is the benefit of using it? Use your textbook and Internet research to draw your conclusions.

A. UDP is suitable for applications that need fast, efficient transmission, such as games. UDP's stateless nature is also useful for servers that answer small queries from huge numbers.

2. HTTP is the common protocol used to retrieve web resources in a web browser. This runs over TCP/IP networks using TCP. What characteristics of TCP make its use in this situation desirable? Use your textbook and Internet research to draw your conclusions.

A. TCP is suited for applications that require high reliability, and transmission time is relatively less critical. TCP has protocols in place that allow data to be transferred to and from connecting devices.

3.4

1. Wireshark gives you the ability to save captured traffic. This can be a great benefit to network administrators, but it can also pose a security risk. What kind of security risks does this present? Use your textbook and Internet research to support your conclusion.

A.

2. The frame encapsulates all other information from the higher layers of the network communication. What kind of information on the network layer encapsulation is available in Wireshark?

A.