Accessibility of Portal 7.3 in Portal 7.0

Hi,

Our existing system is EEC 6.0 EHP4 , Portal 7.0 &SRM 5.0.Now our business requirement is to configure ECC 6.0,EHP 4,SRM 7.02 in portal 7.3 and provide access for the same s in portal 7.0.Because all users must want to login first in portal 7.0(requirement)

My understanding is for getting it is is to establish SSO between Portal 7.0 and Portal 7.3 and provide access (portal 7.30 in portal 7.0 by creation URL iView and assigning the role to the concern users.

Is it a correct way to achieve the requirements..? Is there any compatibility issue will occur in doing so, as portal 7.0 as a produced and portal 7.3 as a consumer portal..?

Thanks,

Kundan