Since Tableau Online has no guest access all users accessing views and dashboards published to Tableau Online must be authenticated. This means that all users must be licensed. Tableau Server may be a better option for your specific needs with a core license which includes Guest access. The following Knowledge Base article provides a comparison between Tableau Online and Tableau Server:
Another option would be to distribute packaged workbooks to users which will allow them to view dashboards in Tableau Reader (for free). However with this approach the workbooks would need to be distributed very regularly to ensure that viewers had current data and there are security concerns around the fact that the packaged workbooks could fall into the wrong hands.
Cool, thanks for the clarification and info Paul.
Paul is correct, however a lot of our clients choose a half step option before graduation to Server.
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