On the impact of fault tolerance tactics on architecture patterns

One important way that an architecture impacts fault tolerance is by making it easy or hard to implement tactics that improve fault tolerance. Information about how the implementation of fault tolerance tactics affects the architecture patterns of a system should be useful to architects during architectural design in selecting optimal fault tolerance tactics and architecture patterns. In order to understand more about how useful this information can be, we performed an informal study of teams designing fault tolerance tactics in an architecture. One group used information about the interaction of tactics and architecture patterns; the other did not. We observed that the group with the information produced better quality architectures, and were able to better estimate the difficulty of implementing the tactics. We recommend that information about the interaction of tactics and architecture patterns be made available to architects, particularly those with less familiarity about fault tolerance tactics.