SEI refers to Software Engineering Institute of Carnegie Mellon University in Pittsburgh, it helps to improve software development process. SEI offers technical guidance for advanced practice in software engineering.
CMM refers to 'Capability Maturity Model', presently called as CMMI 'Capability Maturity Model Integration’; it was developed by SEI and used to understand the processes followed in as organization. CMMI ratings were given to organizations after review by auditors.
CMMI has five levels of process maturity for quality software delivery, they are,
Level 1 – In this level only few processes were used and to rely on individual efforts for successful completion of projects.
Level 2 – In this level there will be realistic planning like project tracking, requirements analysis, configuration management.
Level 3 – In this level a proper software development and maintenance are incorporated throughout the organization. Training programs are exercised for better understanding of the process.
Level 4 – In this level various metrics are used to follow the process and products. The delivery quality is high.
Level 5 – In this level new process and technology were used and implemented efficiently. The objective will be for consistence process development.
ISO is commonly known as 'International Organization for Standardization', the ISO 9001:2000 standard is used for quality systems audited by outside auditors. This standard is applicable for manufacturing companies not only for software. This standard is given based on the documentation, design, production, testing, servicing and other processes.
IEEE refers to 'Institute of Electrical and Electronics Engineers', which has members from many technical professional organizations around the world. IEEE 829 is the standard followed for software test documentation.
ANSI refers to 'American National Standards Institute', which manages the development of standards for products, services, personnel, processes, and systems in U.S. This organization also works with other international standards to make use of American products worldwide.