A) For each address that appears in H2, H3, H4 in the fields of the next FRAME, explain what it is, specify the number of bits representing the address. And is the address handled by the end unit, the router and the switch? (switch)

B)B. The following abstract drawing describes the structure of the router. Its top entry port on the left, 1, is connected to a local access network. The upper right exit port, 20, goes out to another router on the Internet. Assume that a user surfing the browser on computer A surfs to server B (top right) using the HTTP protocol over TCP. The package leaving computer A for the purpose of establishing the connection is described in detail in section A. According to the fields of H2, H3, H4 on the following questions:

a. What are the IP addresses of computers A and B? b. Who do the two MAC addresses listed in H2 belong to? Describe the process that resulted in finding these MAC addresses (the ARP protocol is only part of the process) c. What does the network card do in port 1 when the packet arrives? d. What does the LOOKUP component do? Refer in the explanation to the corresponding field in the drawing of the package in section A. e. What is done in the port 20 PORT components? What are all the fields of the FRAME coming out of the router's exit detail towards B?

\begin{tabular}{|c|c|c|c|c|} \hline \multicolumn{1}{|c|}{H2} & H3 & H4 & & \\ \hline 71-65-F7-2B-08-53 & 223.1.3.2 & 6428 & & data \\ 1A-2F-BB-76-09-AD & 137.196.7.23 & 80 & (payload) & CRC \\ \hline \end{tabular}