protected String getHost(ServletRequest request) {
        return request.getRemoteHost();
    }
Returns the host name or IP associated with the current subject.  This method is primarily provided for use
during construction of an <code>AuthenticationToken</code>.
<p/>
The default implementation merely returns {@link ServletRequest#getRemoteHost()}.

@param request the incoming ServletRequest
@return the <code>InetAddress</code> to associate with the login attempt.
web/src/main/java/org/apache/shiro/web/filter/authc/AuthenticatingFilter.java