Overview
ISO/IEC 14776-411:1999 - SCSI-3 Architecture Model (SCSI-3 SAM) defines the architecture and generic requirements that govern SCSI-3 implementations. The standard provides a reference model and a set of common behavioral requirements used to transform generic requirements into measurable, implementation-level requirements for any SCSI-3 device, interconnect or protocol. It is intended to ensure consistent host software and device firmware behavior so that SCSI-3 I/O systems interoperate reliably.
Key Topics and Requirements
This part of the ISO/IEC 14776 series addresses core architectural and behavioral elements of SCSI-3 (SAM), including:
- Reference and structural models
- Distributed service model, client–server model and structural/domain models for SCSI-3 systems.
- Device and object models
- Definitions for SCSI Device, Initiator, Target, Logical Unit and Task Manager objects and hierarchies.
- Command and protocol model
- SCSI Command Model (Command Descriptor Block, operation codes, control fields), status reporting and protocol services for execute-command operations.
- Data transfer and delivery services
- Protocol services supporting Data-In and Data-Out, buffered transfers and related transaction models.
- Task and task-set management
- Task lifetimes, task attributes (SIMPLE, ORDERED, HEAD OF QUEUE, ACA), task-management functions (ABORT TASK, TARGET RESET, etc.) and state/transition diagrams.
- Error and exception handling
- Sense data, unit attention, auto contingent allegiance, hard reset behavior and asynchronous event reporting.
- Normative conventions
- Definitions, numeric and editorial conventions, object notation and state diagrams used across SCSI-3 documents.
Practical Applications
ISO/IEC 14776-411:1999 is used to:
- Define interoperable behavior for host drivers, storage firmware and device controllers.
- Guide protocol designers and implementers when creating SCSI-3 transport and interconnect standards.
- Serve as a reference for conformance and interoperability testing, compliance labs and quality assurance teams.
- Inform system architects building enterprise storage, SAN components, RAID controllers and embedded storage devices that use SCSI semantics.
Who Should Use This Standard
- Firmware engineers and device driver developers
- Storage system architects and hardware designers
- Test and QA engineers focused on interoperability and conformance
- Standards developers and technical committees coordinating SCSI-3 implementations
Related Standards
This document is Part 411 of the ISO/IEC 14776 SCSI-3 family. Its generic requirements are intended to be transformed by other SCSI-3 implementation standards (protocol- or interconnect-specific) into concrete, measurable implementation requirements used across the SCSI ecosystem.
Keywords: ISO/IEC 14776-411, SCSI-3, SCSI-3 Architecture Model, SCSI SAM, SCSI command model, task management, SCSI device interoperability.