CCNA Chapter 10

What are the three primary functions of the presentation layer?

1. Formats, or presents data from source into compatible form for receipt by the destination device. 2. Compresses data in a way that it can be decompressed by destination device. 3. Encrypts the data in a way that it can be decrypted by the destination device.

What are the seven OSI layers?

7. Application 6. Presentation 5. Session 4. Transport 3. Network 2. Data Link 1. Physical

What are the four TCP/IP layers?

Application Transport Internet Network Access

Which OSI layer correspond to TCP/IP layers?

Application, Presentation, and Session layers of OSI correspond to Application layer of TCP/IP. Transport corresponds to Transport Network layer corresponds to Internet Data Link and Physical layers correspond to Network Access

Name seven of the most widely known application layer protocols

DNS, HTTP, SMTP, POP, DHCP, FTP, IMAP

What does the OSI application layer do?

It provides the interface between the applications we use to communicate and the underlying network over which our messages are transmitted.

Name five of the most widely known presentation layer protocols

Quicktime, MPEG, GIF, JPEG, PNG

What does the session layer do?

The session layer creates and maintains dialogs. It initiates them, keeps them active, and restarts them if they are interrupted or idle.