Question 1.
Which OSI layer is aware of the existence of files, as distinct from individual records?

a) Application
b) Session
c) Transport
d) Presentation

Answer

Question 2.
What layers do (1) FTP and (2) TFTP belong to?

a) Both are application layer protocols.
b) FTP is an application layer protocol, but TFTP is stripped-down and only has session layer functions.
c) TFTP is the transport layer protocol (transport FTP) for the application-layer FTP. FTP does not use a separate presentation protocol.
d) TFTP is a subset of application-layer FTP.

Answer

Question 3.
Electronic mail (i.e., messaging) protocols are part of what layer of the OSI Reference Model?

a) Presentation
b) Transport
c) Application
d) Session

Answer

Answers

Question 1.
Which OSI layer is aware of the existence of files, as distinct from individual records?

a) Application
b) Session
c) Transport
d) Presentation

Answer
a) Application

Explanation
File Transfer Protocol (FTP) and database protocols are functions of the application layer. File transfer formats are really above the Application Layer, although on the CCNA exam, Cisco may ask about file formats such as JPEG and MPEG. Cisco incorrectly places those formats at the Presentation Layer.
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Question 2.
What layers do (1) FTP and (2) TFTP belong to?

a) Both are application layer protocols.
b) FTP is an application layer protocol, but TFTP is stripped-down and only has session layer functions.
c) TFTP is the transport layer protocol (transport FTP) for the application-layer FTP. FTP does not use a separate presentation protocol.
d) TFTP is a subset of application-layer FTP.

Answer
a) Both are application layer protocols.

Explanation
FTP and TFTP are two distinct application-layer protocol. FTP runs over TCP, while TFTP runs over UDP. The overriding design objective for TFTP was that its implementation code be very small and simple, so it can fit into the ROM of a router or diskless workstation.TFTP is intended to get bootable images and other very restricted system software, while FTP is a general file transfer protocol. FTP does not have separate presentation and session protocols, but FTP does have the ability to negotiate a presentation context for binary or text transfer.
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Question 3.
Electronic mail (i.e., messaging) protocols are part of what layer of the OSI Reference Model?

a) Presentation
b) Transport
c) Application
d) Session

Answer
c) Application

Explanation
Application layer protocols interface directly to application software on hosts. Be aware of the distinction between application software, which interfaces to the user, and application protocols, which interface to other hosts.
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[NA-OSI-SQ1-Fxx]
[1999-07-29-01]