sudoku remote play game in group  web services

The Sudoku is a popular puzzle game. In this implement two Sudoku remote/web services: 1. Sudoku solver remote service that solves given Sudoku puzzles. 2. Sudoku generator web service that generates new Sudoku puzzles. Clients use these services in order to solve given Sudoku puzzles and to generate new Sudoku puzzles given the size of the regions e.g., 2, 3, 4… (the grid size equals the region size squared) and the number of empty squares. In order to support multiple requests in parallel, the actual Sudoku solving will be done by several back end servers. The service load will be balanced among them and they will back up each other in case of failures. The service should support adding and removing of back end servers, load balancing among them and recovery from a crash of any back end server. In this extend the distributed system for providing Sudoku Remote/Web services in order to support group playing and fault tolerance of the front end server. In the extended system clien