Homework 7

CIS 331: Network Introduction
Lehman College, City University of New York
Fall 2014

This Homework Is Due By 11:59 PM on Sunday November 9, 2014

1. Explain the use of the pseudo-header for a UDP datagram and TCP segment. When is it used? Is it transmitted with the datagram? How does the ultimate destination obtain the contents of the pseudo-header?


2. What is the chief advantage of using protocol ports instead of process identifiers to specify the destination within a machine?



3. Given that a frame is formatted as follows:

   

   And given that an IP datagram is formatted as follows:

   

   And given that a UDP datagram is formatted as follows:

   

   And given the following frame with an encapsulated IP datagram and UDP datagram:

   
   
   
   1. What is the UDP source port?
   2. What is the UDP destination port?
   3. What is the UDP message length?
   4. What is the UDP checksum?
   5. If the UDP header and the IP header include no options or padding, what are the first five bytes of the datagram data?



4. Given that a frame is formatted as follows:

   

   And given that an IP datagram is formatted as follows:

   

   And given that a TCP segment is formatted as follows:

   

   And given the following frame with an encapsulated IP datagram and TCP segment:

   
   
   
   1. What is the TCP source port?
   2. What is the TCP destination port?
   3. What is the Sequence Number?
   4. What is the Acknowledgment Number?
   5. What flags are set?
   6. What is the Window Size?
   7. What is the checksum?
   8. What is the urgent pointer?
   9. If the TCP header and the IP header include no options or padding, what are the first five bytes of the TCP segment data?

Please submit the completed assignment on Blackboard as a Microsoft Word file or a PDF file. No other forms of submission will be accepted.