ISOSPiCE is15504

ISO/IEC 15504

ISO/IEC TR 15504 the international standard for Software Process Assessment was first published in 1998 as Technical Report Type 2. A standard is published as a Technical Report Type 2, when the subject is still under technical development, or where for any other reason there is the future possibility of an agreement on an International Standard. The development of ISO/IEC 15504 has taken place in parallel with empirical studies of its use undertaken by the SPICE project.

A Technical Report Type 2 is subject to review within three years of publication, to decide whether it can be transformed into International Standard. In accordance with this, work on the revision of ISO/IEC 15504 commenced immediately the document set was published.

ISO/IEC 15504 has subsequently been published as a full international standard during 2003/2006 as a five- part standard under the general title Information Technology — Process Assessment. It consists of the following parts:

• Part 1 - Concepts and vocabulary
• Part 2 - Performing an assessment
• Part 3 - Guidance on performing an assessment
• Part 4 - Guidance on use for process improvement and process capability determination
• Part 5 - An exemplar process assessment model

THE MAIN CHANGES

The main changes that occur from the ISO/IEC TR 15504 to ISO/IEC 15504 are as follows:

1. The name change from Software Process Assessment to Process Assessment
2. The restructuring of the standard from 9 parts to 5 parts
3. The inclusion of an exemplar assessment method
4. The removal of the Process Dimension which now resides in an annex to ISO/IEC ISO 12207 and is published as ISO/IEC 12207 AMD1 and AMD2
5. The introduction of the concept of Process Reference Models
6. The revision and alignment of the Capability Dimension with ISO9001: 2000

The uptake of ISO/IEC 15504 has created the need for confidence in assessors performing assessments. As a result an International Assessor Certification Scheme (INT-ACS) has been introduced. The purpose of the scheme is to certify as competent assessors trained and qualified in the principles and practices of assessing processes using ISO/IEC 15504. There are three grades of assessor defined:

• Provisional Assessor
• Assessor and
• Principal Assessor

The provisional assessor grade is an entry grade for individuals with appropriate education, training and skills but that lack assessment experience. The assessor grade is de- fined for individuals with experience and that can lead and assessment. The principal assessor grade is for assessors with extensive experience and that have lead assessment teams. The principal assessor grade is targeted at consultants, procurement organizations and certification bodies.

The major benefit of the change is that it expands substantially the available scope of the standard. Instead of being constrained solely to software life cycle processes, it now defines a common assessment approach that can be applied to any processes.

Within the revised ISO/IEC 15504 process assessment is based on a two dimensional model containing a process dimension and a capability dimension. The process dimension is provided by an external Process Reference Model (PRM), that defines a set of processes characterized by statements of process purpose and process outcomes. The capability dimension consists of a Measurement Framework comprising six Process Capability Levels and their associated Process Attributes. The assessment output consists of a set of process attribute ratings for each process assessed, termed the Process Profile, and may also include the capability level achieved by that process.

The capability dimension has been updated to address some weaknesses highlighted through use of ISO/IEC TR 15504 and also to fully align with the concepts in the published process oriented ISO 9001:2000. The initial input of changes for the alignment of the capability dimension to ISO 9000:2000 resulted from a study performed by the European SPACE Agency into the application of process assessment techniques to quality management systems.

Apart from minor changes in the wording and ordering of process attributes in the measurement framework, the major changes are in the detail of the measurement framework at levels 2 and 3. Much greater detail has been incorporated, and more formal traceability to ISO 9001:2000 has been included. The distinction between process definition and process deployment has also been made at level 3. At levels 4 and 5 the levels have been reworked to clarify the relationship between “Process Capability” as defined in ISO/IEC 15504, and conventional concepts of Statistical Process Control. Level 4 (the Predictable Process) is concerned with the ability to identify and address special causes of process variation. Level 5 (the Optimizing Process) is concerned with the ability to identify and address common causes of process variation.

PROCESS REFERENCE MODELS

Process Reference Models may be developed outside of the ISO standardization providing they meet certain requirements for conformity and compliance. Process Reference Models exist or are already under development in the areas of:

• Software lifecycle processes – through ISO/IEC 12207 AMD1/2
• System lifecycle processes – through ISO/IEC 15288
• Human centered lifecycle processes - through ISO 18529
• Component-based development processes – through the OOSPICE project
• IT service management processes - through a SPICE User Group initiative
• Quality management system processes - through SPICE for 9000 (S9K)
• Automotive embedded software – through Automotive SPICE, an initiative of The Procurement Forum and The SPICE User Group with the major European car manufacturers (see home page for information presentation - Automotive SPICE web site under development)
• Medical device software - through the Medi SPICE initiative

HOW TO OBTAIN THE STANDARD

Copies of the published ISO/IEC 15504 standard can normally be purchased in the public domain from National Standards Bodies.

Only participating members of National Standardisation Bodies or bodies in liaison (e.g. The SPICE User Group) have access to standards under development.

Members of the SPICE User Group may obtain a 40% discount on the published standard.