IMS

Information Management System

Enhanced Definition

IBM's hierarchical database and transaction processing system, designed for high-volume online and batch processing. IMS has been a cornerstone of enterprise computing since the 1960s.

Key Characteristics

- Hierarchical database model
- High-performance transaction processing
- Proven reliability and availability
- Massive scalability
- Billions of transactions daily capability
IMS Components:
- IMS DB: Database management system
- IMS TM (DC): Transaction Manager/Data Communications
- IMS Connect: TCP/IP connectivity
- DBCTL: Database Control facility
- DCCTL: Data Communications Control facility
Database Structure:
- Segments: Hierarchical data nodes
- Parent-Child Relationships: Tree structure
- Physical Databases: Physical storage structure
- Logical Databases: User view of data
- Secondary Indexes: Alternative access paths
Transaction Processing:
- Message-driven architecture
- Message queues for input/output
- Transaction scheduling
- Parallel processing capability
- Automatic restart and recovery
Program Types:
- Batch Programs: Offline processing
- Message Processing Programs (MPPs): Online transactions
- Fast Path Programs: Ultra-high-performance transactions
- Batch Message Processing (BMP): Mixed mode processing

Use Cases

- Banking transaction processing
- Airline reservation systems
- Healthcare claims processing
- Retail point-of-sale systems
- Government benefit programs