Sandeep,
The ValidTargetDomain has been introduced for Security purpose.
From the 12SP3 Webagent Configuration Guide:
How to Configure a CA SiteMinder Agent to Support HTML Forms Authentication
Define Valid Target Domains
To configure SiteMinder Agents to help protect your resources from phishing attempts that could redirect users to a hostile website, set the following configuration parameter:
- ValidTargetDomain
Specifies the domains to which a credential collector is allowed to redirect users. If the domain in the URL does not match the domains set in this parameter, the redirect is denied.
Default: No.
All advanced authentication schemes, including forms credential collectors (FCCs) support this parameter.
The ValidTargetDomain parameter identifies the valid domains for the target during processing. Before the user is redirected, the agent compares the values in the redirect URL against the domains in this parameter. Without this parameter, the agent redirects the user to targets in any domain.
The ValidTargetDomain parameter can include multiple values, one for each valid domain.
For local Web Agent configurations, specify an entry, one entry per line, for each domain, for example:
validtargetdomain=".xyzcompany.com"
validtargetdomain=".abccompany.com"
Hope it helps,
Julien.