(60 Marks) There are SIX (6) questions in this question paper. Answer ALL questions in the answer booklet. 1. Multiplexing is a method that can be used to combine multiple analog or digital signals into one signal over a shared medium. a) Why do organizations implement multiplexing on their networks? Justify your answer with any TWO (2) reasons. (4 Marks) b) A cable TV service uses a single coaxial cable with a bandwidth of 960 MHz to transmit multiple TV signals to subscribers. Each TV signal is 6 MHz wide. How many channels can be carried? 2. (3 Marks) [Total: 7 Marks] In CDMA (Code Division Multiple Access) systems, there are 30 simultaneous users in the system. Find the number of different codes used. Justify your answer. (4 Marks) 3. Suppose there are two Internet Service Providers (ISP) providing 11Mbps Wi-Fi access in a particular cafe, with each ISP operating its own Access Point (AP) and having its own IP address block. Both ISPs had configured their AP to operate over channel 11. a) Can the two ISPS work in parallel over the same channel? Justify your answer. (3 Marks) b) Discuss what happens at the frame level, when two stations (STA), each associated with a different ISP, attempt to transmit at the same time. (8 Marks) c) If you are tasked to monitor the cafe's network and found a rogue AP in the network, what steps should be taken by you to ensure the damage is minimized? 3 (6 Marks) [Total: 17 Marks]