問3
頻出度★☆☆
SOA (Service Oriented Architecture) とは, サービスの組合せでシステムを構築する考え方である。SOA を採用するメリットとして, 適切なものはどれか。
平成26年度 春期 ITパスポート試験 問3
ストラテジ系システム戦略 › 情報システム戦略
This question's explanation and your answers so far.
解説
問 3
Incorrectア
SOA is not a technology whose purpose is to improve processing speed. On the contrary, because services exchange data over a network through standardized interfaces, communication and data-conversion overhead is added compared with completing the processing inside a single program, so response time is often worse instead. Improvements in processing speed are pursued by other means, such as upgrading hardware or tuning algorithms and databases.
Incorrectイ
SOA is an approach concerning the structure of a system (how it is divided into components and combined); it is not in itself a mechanism that strengthens security. If anything, because functions are distributed across multiple services on a network and more interfaces can be called from outside, the places open to attack may actually widen. Ensuring security requires separately designing and implementing security measures such as authentication, authorization, encryption of communication, and access control.
Incorrectウ
SOA is about the internal architecture as seen by developers, and it does not guarantee that the screens users operate or the business procedures are easy to understand. Even if a system is divided into components, the input and judgments that users have to make do not disappear, so training and instruction on operating methods and business rules are still needed as before. The effect of making training unnecessary cannot be derived from adopting SOA.
- エ
正解 The correct answer is エ, “Flexible system development becomes possible.” SOA (Service Oriented Architecture) is a design philosophy in which business functions such as order taking, inventory inquiry, and credit checking are each turned into independent components called “services,” and a system is built by combining those services through standardized interfaces. Each service is a loosely coupled component that does not depend on the internal implementation of other services, so when a business process changes, you can respond simply by rearranging the combination of services or the order in which they are called, without rebuilding the entire system. In addition, services that already exist can be reused by other business systems, which also helps shorten development time and improve maintainability. In short, the effect SOA aims for is the “flexibility” to follow changes in the business environment quickly, and choice エ matches that intent.
ここがポイント
- Definition of SOA (Service Oriented Architecture): an approach in which business functions are turned into highly independent components called “services,” and a system is built by linking them loosely through standardized interfaces. Because services can be rearranged and reused unit by unit, the main advantages are the flexibility to follow changes in business quickly, and improved development efficiency and maintainability through reuse.
- The key is to separate out what effect a given technology is originally aiming for. Improved processing speed, stronger security, and reduced user training are not effects obtained directly from the SOA design philosophy; they belong to areas handled by other measures — performance tuning, security countermeasures, and UI design or operational training, respectively.