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Which layer of the TCP/IP stack combines the OSI model physical and data link layers?
A. Internet layer
B. transport layer
C. application layer
D. network access layer
Answer: D
Explanation:
The Internet Protocol Suite, TCP/IP, is a suite of protocols used for communication over the internet. The TCP/IP model was created after the OSI 7 layer model for two major reasons. First, the foundation of the Internet was built using the TCP/IP suite and through the spread of the World Wide Web and Internet, TCP/IP has been preferred. Second, a project researched by the Department of Defense (DOD) consisted of creating the TCP/IP protocols. The DOD’s goal was to bring international standards which could not be met by the OSI model. Since the DOD was the largest software consumer and they preferred the TCP/IP suite, most vendors used this model rather then the OSI. Below is a side by side comparison of the TCP/IP and OSI models.
TCP/IP Model
VS.
OSI Model Application Layer 7
Application
Layer 6
Presentation
Layer 5
Session Transport Layer 4
Transport Internet Layer 3
Network Network Access Layer 2
Data Link
Layer 1
Physical
