Overview

In a load balanced environment the default singleton implementation doesnt work out of the box.

There is two solution in order to achieve captcha validation throught load-balancing

• Use a "distributed singleton" implemented with an distributed cache CaptchaStore (like JBossCache)
• Use sticky session

The JBossCacheStore allows JCaptcha to be used in a clustered environment, generated captchas are stored in a distributed Cache. A user can now retrieve a captcha from a node and validate it on another node.

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