CSC4808 TEST Instruction: Answer all Question Time Allowed: the 30 Marks Q1 (a) 1. Give the difference between the network G, 2G 2,50, 3G mobile manu ". What does Digital Signature means? And briefly the term wireless and state the (b) i What is the purpose of S- boxes in DES? ii. Describe three (3) alternative approaches to providing WAP end-to-end security Q2. (a)i. What are two different kinds of mobility? ii. Find out the characteristics while device can thus exhibil during communication. (b) i. What are applications of Mobile Computing? i. What are the obstacles in mobile communications? (e) i. What is Mobile Computing and the applications? V ii. Enumerate five (5) limitations of Mobile Computing? Q3. (a) i. Differentiate between two tier and three tier client/server architectures ii. Differentiate between fat server and the fat client. (b) i. List out the characteristics of client server computing. ii. Define Intergalactic client/server. (e) i. List out the technologies is needed in the Intergalactic client/server. ii. List out the 4 situations used for building blocks arrangement​