$($a$)$ Designers are to configure a network for a medium$-$sized company which is engaged in the development of multi$-$functional software products. The product development requires intensive interaction within various groups in the company, each group working on a particular function of the product. The groups also need to interact from time to time with each other at the level of their managers in order to test the integrated product with contributions from each group, and to monitor the overall project progress. $($i$)$ What structural model $($or models$)$ you would advise to be employed by the company? Explain why. $($ii$)$ Draw schematically the suggested network configuration$($s$).($iii$)$ What are advantages and disadvantages of peer$-$to$-$peer and client$-$server networking? $($b$)$ A station attached to the CSMA$/$CD Ethernet LAN is transmitting $600$ bytes of data using the MAC frame shown in Figure $1\mathrm{.}1.$ The LAN operates at $100$ Mb$/$s over a $2-$km cable with $3$ repeaters. The one$-$way signal delay in one repeater is $5\backslash$mu s$.$ The signal speed in the cable is $200,000$ km$/$s$.$ Figure $1\mathrm{.}1($i$)$ Explain how the CSMA$/$CD protocol works. $($ii$)$ Calculate the amount of padding $($in bytes$)$ which is needed to be added to the data. Assume that no safety margin bits are used. Question