Page 77, P31. In moden packet - switched networks, including the Internet, the source host segments...

Transcribed Image Text:

Page 77, P31. In moden packet - switched networks, including the Internet, the source host segments long, application - layer messages ( for example, an image or a music file) into smaller packets and sends the packets into the network The receiver then reassembles the packets back into the original message. We refer to this process as message segmentation. Figure 1.27 illustr ates the end - to - end transport of a message with and without message segmentation. Consider a message that is 8 x 10 6 bits long that is to be sent from source to destination in Figure 127. Suppose each link in the figure is 2 Mbos. Ignore propagation, queuing, and p rocess ing delays. a. Consider sending the message from source to destination without message segmentation. How long does it take to move the message from the source host to the first packet switch? Keeping in mind that each switch uses store - and - forward packet s witching, what is the total time to move the message from source host to destination host? b. Now suppose that the message is segmented into 800 packets, with each packet being 10,000 bits long. How long does it take to move the first packet from source host to the first switch? When the first packet is being sent from the first switch to the second switch, the second packet is being sent from the source host to the first switch. At what time will the second packet be fully received at the first switch? CHow long does it take to move the file from source host to destination host when message segmentation is used? Compare this resuit with your answer in part (a) and comment d. In addition to reducing delay, what are reasons to use message segmentation? e.Discuss the drawbacks of message segmentation Page 77, P31. In moden packet - switched networks, including the Internet, the source host segments long, application - layer messages ( for example, an image or a music file) into smaller packets and sends the packets into the network The receiver then reassembles the packets back into the original message. We refer to this process as message segmentation. Figure 1.27 illustr ates the end - to - end transport of a message with and without message segmentation. Consider a message that is 8 x 10 6 bits long that is to be sent from source to destination in Figure 127. Suppose each link in the figure is 2 Mbos. Ignore propagation, queuing, and p rocess ing delays. a. Consider sending the message from source to destination without message segmentation. How long does it take to move the message from the source host to the first packet switch? Keeping in mind that each switch uses store - and - forward packet s witching, what is the total time to move the message from source host to destination host? b. Now suppose that the message is segmented into 800 packets, with each packet being 10,000 bits long. How long does it take to move the first packet from source host to the first switch? When the first packet is being sent from the first switch to the second switch, the second packet is being sent from the source host to the first switch. At what time will the second packet be fully received at the first switch? CHow long does it take to move the file from source host to destination host when message segmentation is used? Compare this resuit with your answer in part (a) and comment d. In addition to reducing delay, what are reasons to use message segmentation? e.Discuss the drawbacks of message segmentation

Answer rating: 100% (QA)

solution below 8x10 a Time to send message from source host to first packet switch sec 4sec 2x10 Wit... View the full answer