This answer is for developers who are leveraging the Yurbi API, for customers who are using Windows authentication, you can simply setup passthrough authentication the Yurbi embed object will not require them to re-login in (assuming they are already logged into the network).
For the most common use case for this feature, you can perform a login (via the DoLogin API call) and then pass the Yurbi session token to the URLs, the parameter is s=sessionToken
For dashboards or reports, the embed URL should be similar, just t=d or t=r:
<iframe src="http://yurbiserver/yurbi/embed.html?t=d&i=164&;s=AJODKVLUMGXYDPNPRF[NCUJIZ" height="600" width="1000"></iframe>
You could also pass in a username and password as well using adding additional parameters: u=username and p=mypassword but this method is less secure.