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.
It is offered in English. Certified Six Sigma Black Belt Required Experience Six Sigma Black Belt requires two completed projects with signed affidavits, or one completed project with a signed affidavit and three years of work experience, in one or more areas of the Six Sigma Body of Knowledge.