Just like WordPress.com and Blogger, now you can easily enable single sign-on on your self-hosted WordPress multisite network and authenticate registered users across all websites within your network.
WP Multisite SSO is the new WordPress plugin that provides you single sign-on for multisite implementation. Great for domain mapped environment where the normal domain authentication cookie would not apply.
It makes use of internal WordPress authentication functions, and maintains native WordPress login page. It simply authenticates user across the network.
Start by inatlling ‘WP Multisite SSO’ in WordPress
Upon network activation, visit its admin options page. Here it provides you settings to customize SSO login/logout loading page by inheriting default WordPress login page CSS, also includes custom login page CSS in theme or specify CSS.