Question: UDP packets have a fixed-size header of _______ bytes.

Answer:

UDP (User Datagram Protocol) packets have a fixed-size header of 8 bytes. The UDP header contains four fields, each of which is 2 bytes long. The fields in the UDP header are as follows:

• Source port number (2 bytes)
• Destination port number (2 bytes)
• Length (2 bytes)
• Checksum (2 bytes)

The source and destination port numbers identify the sending and receiving processes, while the length field specifies the length of the UDP datagram, including the header. The checksum field is used to verify the integrity of the data and the header. Because the UDP header is fixed in size, the maximum size of a UDP datagram is limited to 65,535 bytes (65,527 bytes of data and 8 bytes of header). However, in practice, the maximum size of a UDP datagram is often much smaller, typically around 1,500 bytes, due to the limitations of the underlying network protocols and hardware.