Review Questions

1.	List the two main advantages of the OSI model.
2.	Which layer of the OSI model is responsible for establishing, maintaining, and synchronizing the data connection?
3.	Which layer of the OSI model is responsible for identifying the source and destination hardware addresses and organizing bits into frames?
4.	Which layer of the OSI model is responsible for file and print services and determines whether a service request should be processed locally or routed to the network?
5.	Which layer of the OSI model is responsible for moving data over an internetwork?
6.	Which layer of the OSI model is responsible for moving bits over physical media?
7.	Which layer of the OSI model is responsible for formatting and translating data?
8.	Which layer of the OSI model is responsible for reliable delivery of data, management of connections, error control, and flow control?
9.	What are the two sublayers of the Data-Link layer?
10.	Which device routes packets between two networks at the Network layer of the OSI model?
11.	What is the difference between connection-oriented services and connectionless services? Which is more reliable? Which is more efficient?
12.	What is the difference between a physical address and a network address?
13.	List the seven layers of the OSI model from bottom to top.

Answers

1.	It makes networking easier to understand. It makes it easier to replace modular components as technology changes.
2.	Session
3.	Data-Link
4.	Application
5.	Network
6.	Physical
7.	Presentation
8.	Transport
9.	Logical Link Control (LLC) and Media Access Control (MAC)
10.	Router
11.	Connection-oriented services establish a connection between the sender and the receiver and are more reliable. Connectionless services send data without establishing a connection and are more efficient.
12.	A physical address is identified at the Data-Link layer of the OSI model and is hard-coded on the network interface card. A network address is associated with the Network layer of the OSI model and is a logical address that the network administrator assigns.
13.	Physical Data-Link Network Transport Session Presentation Application