In distributed database classifications, what is an autonomous homogeneous environment?
-
AThe same DBMS is at each node and each DBMS works independently.
-
BThe same DBMS is at each node and a central DBMS coordinates database access.
-
CA different DBMS is at each node and each DBMS works independently.
-
DA different DBMS is at each node and a central DBMS coordinates database access.
Answer
Correct Answer: The same DBMS is at each node and each DBMS works independently.
Explanation
Introduction / Context:Distributed databases are often categorized along two axes: homogeneity versus heterogeneity (same versus different DBMS products) and autonomy versus central control (local independence versus global coordination). This classification guides design choices and middleware needs.
Given Data / Assumptions:
- Homogeneous: identical DBMS engines at all nodes.
- Autonomous: nodes operate independently without a central controller.
- Networked environment interconnects the nodes.
Concept / Approach:An autonomous homogeneous environment means each site uses the same DBMS software yet retains local control over its data and transactions. Global queries may require federation, but there is no single central DBMS dictating access.
Step-by-Step Solution:
Check “homogeneous” → same DBMS everywhere.Check “autonomous” → no central coordinator; independent operation.Pick the statement that matches both characteristics.Verification / Alternative check:Taxonomies in distributed DB literature contrast this with “tightly coupled” (central coordination) or “heterogeneous” (different products) environments.
Why Other Options Are Wrong:
- B: same DBMS but not autonomous (central coordination).
- C/D: heterogeneous, not homogeneous.
Common Pitfalls:Assuming homogeneity implies central control; they are independent axes.
Final Answer:The same DBMS is at each node and each DBMS works independently.