After creating an API, you might want to change its behavior, authentication mechanism, resources supported by it, throttling tiers, target audiences etc. at a later point in time, depending on new business or technical needs of the organization. With these changes, you can publish But, you cannot do these changes to an API that is already published and has users plugged into it. A published API should be fixed. The way to modify it is by publishing a new version of the API and with changes. Depending on the changes, you can decide to depreciate the old one API after a defined period of time, so that the users have time to test their applications with the new API. The API Manager facilitates API versioning as part of API life cycle management.
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