Wireless LANs a) [4 marks] What is the difference between an infrastructure basic service set and an independent basic service set? Which of these uses an access point? What would you use an independent service set for? b) [2 marks] What is a distribution system with regards to an extended service set? c) [1 marks] What is the purpose of various spread-spectrum techniques? d) [4 marks] Describe frequency hoping spread spectrum. e) [4 marks] How is coordination achieved using the distributed coordination function? How is coordination achieved using the point coordination function