The IBM AS/400 (now IBM i) is a highly integrated system designed for business computing. Its key components include:
1. Hardware Components :
- Processor (CPU): Uses IBM Power architecture (earlier used CISC, later migrated to RISC-based Power processors).
- Memory (RAM): Supports virtual memory management and efficient workload handling.
- Disk Storage (DASD - Direct Access Storage Device): Utilizes RAID for data redundancy and reliability.
- Workstations & Terminals: Often uses 5250 terminals for interactive sessions.
- Communication Hardware: Includes Ethernet, TCP/IP, and legacy SNA (Systems Network Architecture) for connectivity.
2. Operating System (OS/400 → IBM i) :
- Object-Based Architecture: Everything (files, programs, devices) is treated as an object, enhancing security and stability.
- Integrated Security: Built-in security features such as user profiles, role-based access, and encryption.
- Automatic Storage Management: The system automatically handles storage allocation and retrieval.
3. Database (DB2 for i) :
- Built-in Relational Database: DB2 for i (formerly known as DB2/400) is tightly integrated with the OS, ensuring high performance.
- Single-Level Storage: Applications and data reside in the same addressable memory space, improving efficiency.
- Native SQL Support: Allows seamless interaction with modern databases.
4. Programming & Development Tools :
- RPG (Report Program Generator): The primary programming language for AS/400 business applications.
- COBOL, CL (Control Language), Java, C, C++: Supports multiple languages for development.
- IBM Rational Developer for i (RDi): A modern development environment for IBM i applications.
- Integrated File System (IFS): Supports hierarchical file structures, enabling compatibility with UNIX/Linux and Windows file systems.
5. User Interface & Access Methods :
- Green Screen Interface (5250 Emulator): Traditional text-based terminal interface.
- IBM Navigator for i: Web-based GUI for system administration.
- Client Access & IBM Access Client Solutions (ACS): Provides remote connectivity from Windows, Linux, and Mac.
6. Networking & Communication :
- TCP/IP, FTP, Telnet: Supports modern networking protocols.
- SNA (Systems Network Architecture): Legacy communication for older systems.
- ODBC/JDBC Connectivity: Allows database access from external applications.
7. System Management & Virtualization :
- Logical Partitioning (LPAR): Enables multiple virtual instances of IBM i on the same hardware.
- IBM PowerVM: Virtualization technology for running multiple OS instances (IBM i, AIX, Linux).
- BRMS (Backup, Recovery & Media Services): Comprehensive backup and disaster recovery solution.
8. Modernization & Cloud Capabilities :
- Web Services & APIs: Supports RESTful and SOAP-based web services.
- Open-Source Support: Compatible with Python, PHP, Node.js, and Git.
- IBM Cloud & Hybrid Integration: Can integrate with cloud services like IBM Cloud and AWS.
