Yes. It is possible to use basic HTTP authentication instead of PDS authentication but only if the user is a locally authenticated user. Please see further information in the following documentation (Authentication section): https://developers.exlibrisgroup.com/rosetta/apis/soap-apis/
If you still prefer to use the PDS authentication then, in general terms, the login() PDS method uses the PDS configuration to find the relevant authentication method and source to be used for authentication and together with the credentials supplied tries to authenticate. If successful it returns a pdshandle for further use in the API. Is this sufficient or do you require more details?
