Normally large messages are broken down into smaller packets, a process called segmentation. In this question, we will compare segmenting to not segmenting (sending the message as one large packet). Suppose Bob wants to send a message that is lvl bits long to Alice. With segmenting, the message is sent as k packets. Without segmenting, it is sent as a single packet of M bits. There are total N routers between Alice and Bob, and each link has bandwidth R bps. Ignore propagation delay and the time to break a message up and reassemble. Until mentioned, ignore headers and loss.
a. With segmentation, what is the time to deliver the full message?
b. Without segmenting, what is the time to deliver the full message?
c. Suppose now each datagram delivered has an h(bits) header, both with and without segmenting. Without segmenting, the whole message is one datagram. With segmenting, each packet is one datagram. In which circumstances do the two approaches have the same end-to-end delay?
d. Based on your answer for question a)~c), if there are many routers along the path, will delivery be faster with or without segmentation?
e. Which mechanism (or behavior) is the root cause of the difference we see in d]? Explain in a few sentences.