Chapter 4, Problem 21Q

Explanation of Solution

Frame layout for Synchronous Data Link Control (SDLC):

• SDLC uses a controlled media access protocol.
• SDLC frame starts and ends with a special bit pattern known as the flag.
• In SDLC, the address field identifies the destination, the length of the address field is generally 8 bits and it can be set at 16 bits.
  • The same network of the computer must use the same length.
• The control field identifies the type of frame in transmission. An information frame and supervisory frame are the two types of frames.
  • An information frame is used for transmitting and receiving the messages.
  • A supervisory frame is used for transmitting acknowledgments.
• The message field is used for variable length and the user’s message.
• The frame check sequence field is a 16-bit or 32-bit Cyclic Redundancy Check (CRC) code.
• It is an efficient protocol for closed private networks with dedicated lines.

Frame layout for Ethernet:

• In the Ethernet packet, the destination address represents the receiver, while the source address represents the sender...