Soft Architectural Distance (SAD): How Far is the Legacy Architecture from SOA Architecture Principle?

Abstract

It is a well-accepted fact that technology is changing rapidly, hence the need to keep upgraded with latest trends is the key to success. This is especially true for big enterprises where the challenge is not only to keep the enterprise running but also to collaborate with other enterprises doing similar business. So, there is a definite need to transform such legacy applications running in organization. This study presented here helps to analyze the current state of LEGACY software architecture and develops a methodology to compare it with Service Oriented Architecture (SOA). The notion of Soft Architectural Distance (SAD) is developed in this work. Degree of SADness will indicate the level of gaps in current architecture w.r.t. Service Oriented Architecture (SOA). Higher the SAD score greater is the GAP and likely to enter in legacy crisis. This SAD score is normalized to value 1 (highest). Then threshold can be defined / decided suitably for any organization. If the evaluation score goes beyond this threshold value it is recommended to improve the architecture or move next steps in legacy transformation strategy. Work is aimed to benefit industry in decision making process for legacy transformation projects. It is also useful in architectural analysis of existing systems.