Businesses are signing on to cloud-based Software as a Service Web apps to cut costs, but that can give rise to another problem — employees may have to sign on to multiple Web apps, and that could lead to security issues. Employees may forget the passwords for some apps, for instance; or someone could hack into a Web application user’s account. Okta, a recently launched San Francisco-based company led by former Salesforce.com executives, is offering an on-demand identity and access management service that may help resolve these problems.