Network servers block
From MoodleDocs
The Network Servers block allows you to roam to other Moodle servers. Works in conjunction with the 'Can roam to other moodles' permission which allows a user to roam to another Moodle site which is part of a Moodle Network. The network feature allows a Moodle administrator to establish a link with another Moodle, and to share some resources with the users of that Moodle.