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An access token is a simple string that is passed as an HTTP header of a request. For example, "Authorization: Bearer NtBQkXoKElu0H1a1fQ0DWfo6IX4a." Access tokens authenticate API users and applications, and ensure better security (e.g., prevent certain types of DoS attacks. Note that DoS attacks made to the key manager with random access tokens can not be prevented. DoS attacks with the same fake acess access token can affect the Gateway as well ). If a token that is passed with a request is invalid, the request is discarded at the first stage of processing. Access tokens work equally well for SOAP and REST calls.
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