application blocking

I have a applicatio开发者_如何学JAVAn which runs over browser ...php application... i need to lock this application to only few machines and laptops that we allow to access. IP locking cannot be done as laptops can be on wifi from outside... Any Idea on how to do this?

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Instead of locking access, allow access from everywhere, but require a login.

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In response to your comment: SSL client certificates are probably what you need. See, for example, here on how to configure this with Apache, or Google for other web servers.