Siteminder ehh,

well from what i found it seems to be another 2nd party helper for security and ease of protetcing important information
read....

SiteMinder provides policy-based authentication as well as single sign-on for all Web-based applications. SiteMinder is used in conjunction with IdentityMinder, which manages detailed user profiles, and TransactionMinder, which provides access to Web services.

im guessing this would be used for a dataCenter or a Webhosting or ISP company, never seen it in action mind you

Hope this helps
Matt