Why Then Did the X.400 E-mail Standard Fail? Reasons and Lessons to be Learned

Abstract

The X.400-series of recommendations specifies the elements, protocols, and services of the e-mail system associated with the Open Systems Interconnection (OSI) protocol stack. The paper looks at the various reasons that led to X.400's failure to gain the widely expected level of market acceptance. A brief literature review suggests that common explanations for success in a standards battle cannot explain the demise of X.400. The same holds for two popular explanations for the victory of Internet over OSI. Therefore, alternative reasons are proposed and discussed, including poor timing of the standardisation activity, inadequate first implementations, and an ill-advised paradigm shift that occurred in the cause of events. Finally, some lessons to be learned for the future are identified.