4. Presentation layer
 - What layer of the TCP/IP reference model is the 
 equivalent of the network layer in the OSI model?
 
 - Physical layer 
 
 - Data link layer 
 
 - Internet layer 
 
 - Transport layer 
 
 - Which of the following are examples of application 
 layer protocols in the TCP/IP reference model?
 (Choose two.)
 
 - TCP 
 
 - HTTP 
 
 - BGP 
 
 - FTP 
 
 - What is the transport layer PDU called in the 
 TCP/IP reference model?
 
 - Data 
 
 - Frame 
 
 - Packet 
 
 - Segment 
 
 - What is the role of the Preamble field in the 
 Ethernet header?
 
 - It is used as padding data to ensure that the frame has at least the 
 minimum number of bytes for transmission.
 
 - It is used as padding data to ensure that the frame has 1500 bytes 
 for transmission.
 
 - It is used to ensure that the frame was transmitted without data 
 corruption.
 
 - It is used to synchronize the signal between the sender and receiver. 
 
 - How many bits are in a MAC address? 
 
 - 24 bits 
 
 - 48 bits 
 
 - 32 bits 
 
 - 64 bits 
 
 - What happens to a data frame for which a switch 
 doesn’t have the destination MAC address in its
 switching table?
 
 - It gets discarded. 
 
 - It gets transformed into a broadcast data frame. 
 
 - It gets sent back to the sender as it cannot be switched. 
 
 - It gets flooded out all the ports except the port on which it was 
 received.
 
