Chapter 3 Homework (50 pts)
Problem 1 (8 pts)
What is the purpose of the length field in the UDP header, and why is it important for data transmission?
Indicates Total Length - which includes both the UDP header and the UDP payload (data). The payload can be of variable length, and this lets UDP know where the segment ends.
Problem 2 (8 pts)
Which set of bytes is used to compute the checksum field in the UDP header, and how does this process work?
The entire UDP segment, except the checksum field itself, and the IP sender and receive address fields. One's complement.
Problem 3 (9 pts)
How does a cumulative acknowledgment, ACK(n), function in networking, and what does it signify?
A cumulative _ACK(n)_ acks all packets with a sequence number up to and including _n_ as being received.
Problem 4 (10 pts)
True or False: When multiple TCP clients send segments to the same destination port at a receiving host, those segments from different senders will always be directed to the same socket at the receiving host. Does the same principle apply to UDP as well?
TCP - False
UDP - True
Problem 5 (5 pts)
True or False: It is possible for two UDP segments to be sent from the same socket with source port 1234 at a server to two different clients.
True
Problem 6 (5 pts)
True or false: It is possible for two TCP segments with source port 8080 to be sent by the server to different clients.
True
Problem 7 (5 pts)
How does a networked application on a server determine the client’s IP address and port number to use when replying to a received datagram?
**UDP**: The client's IP address and port are included in the UDP header, which is accessible at the time the datagram is received.
**TCP**: When the server calls _accept()_, it retrieves the client's details from the underlying transport layer. The information is derived from the TCP segment header, which includes the source IP address and port number of the client.
Submit
Post your solutions in Marmoset by the scheduled due date in the syllabus.
