The Public Switched Telephone Network - The public switched telephone network (PSTN) is the international network of circuit-switched telephones. Learn more about PSTN at HowStuffWorks. x
Black Belt Certification. The IASSC Certified Lean Six Sigma Black Belt (ICBB) is a professional who is well versed in the Lean Six Sigma Methodology, who leads improvement projects, typically in a full-time role. A Lean Six Sigma Black Belt possesses a thorough understanding of all aspects within the phases of D-M-A-I-C.
Six Sigma White Belt Training & Certification. Overview. The Six Sigma White Belt is a course designed to provide the most basic level of understanding of the Six Sigma Methodology. It aims to provide you with a basic definition, history, and structure of the discipline.