Two fault tolerant token based algorithms with logical ring for mutual exclusion in distributed systems

In this paper by using logical ring in network we have presented two algorithms for mutual exclusion in distributed systems. In the first algorithm the token always travels in the ring and each processes going to enter the critical section should wait for token. In the other algorithm the place of token is fixed until not one process is going to enter in critical section; and any process going to enter the critical section, by using a message searches the ring for the token. These algorithms are fault tolerant against crashing any process or losing token.