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The creation of a Business Service Map requires that there be a logical and easily communicated taxonomy that is both structurally sound as well as flexible to handle both known edge cases as well as unknown future cases.
IT Service Taxonomy is a logical hierarchy of IT services to use in future development of IT service portfolio and later IT service catalog. IT Service Taxonomy (ITST) identifies the common and distinguishing characteristics of the services to increase discoverability and reuse. When there is IT service taxonomy, it is easy to recognize the services for the portfolio and catalog. 1
\IT SERVICE (Note: This is a generic service like Storage or Email)
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The Business Service Map is a graphical depiction of the relationship between Configuration Items that assists in understanding the configuration of services and applications. It can be used to evaluate current state as well as to understand the impact of change or incident.
(1) "An IT Service Taxonomy for Elaborating IT Service Catalog" – Md Forhad Rabbi – Blekinge Institute of Technology 12/2009