5. Difference between Grid and Cluster Highly Available . Good quality of service Highly Volatile, resource join and leave. No guarantee of quality of Service Availability It is High Performance Computing It is High Throughput Computing (HTC) Computing Only access to the nodes of the Cluster and its attached storage. It gives transparent access to whatever resources connected. Transparent Access Mostly Open Source Software's Mixture of Open Source and Proprietary Software's used Centralized scheduling, Fault Tolerance and security. Everything is distributed, concept of Local resource managers and Resource brokers Fault Tolerance Scheduling Security Ranges from 10 to 100k Ranges from 10s to millions Number of Nodes Centralized Distributed Job Management System Yes No Number of autonomous systems Single system Image Homogeneous (only one kind of processor) Heterogeneous (Pentium, AMD, PowerPC, Different Operating systems, Multiple owners) System Cluster Grid Characteristics