Module Code: COMP321101 Module Title: Distributed Systems
Examination Information
Question 3
(a) You would like to access the following URI from a local machine: http://BucketName.s3.amazonaws.com Assume that there is a root server R available, and com, amazonaws, and s3 are administrative zones for the URL you are trying to access. Draw a diagram showing the recursive name resolution process, assuming that no part of the name is cached at any of the servers. Number your steps, and at each step, show the information that is being passed between the name servers. [4 marks] (b) Consider the checkout counter at a large supermarket chain. For each item sold, it generates a record of the form (ProductId, Supplier, Price) where ProductId is the unique identifier of a product, Supplier is the supplier name of the product and Price is the sales price for the item. Assume that the supermarket chain has accumulated many terabytes of data over a period of several months. The sales manager wants a list of suppliers, listing for each supplier the average sales price of items provided by the supplier. How would you organise the computation using the MapReduce computation model? [6 marks] (c) A large infrastructure as a service cloud provider wants to allow users to provision new server capacity from a variety of different interface technologies. Which Web technologies should the service provider use to build an interface that users can leverage? [4 marks] (d) Strawberries growing in greenhouses are very susceptible to two main factors: air temperature (significant from the coverage of the greenhouse up to harvest) and water irrigation amount (very important both during the first few months after planting and before harvest). Propose a cloud computing-based solution that allows to instantly check environmental and production parameters and generate notifications when urgent corrections are needed. Discuss how to deploy your solution and include any information that you feel is relevant to back it up. [6 marks] [Question 3 Total: 20 marks]