SURF hosts a single Mastodon instance, https://social.edu.nl/, and only people who are currently part of the SURF network can join. People join via their existing institution ID, which allows them to skip the registration process and decide whether to stay anonymous or use their own identity. Managed group accounts are also available, which is perfect for group collaborations without password sharing.
GNU social JP is a social network, courtesy of GNU social JP管理人. It runs on GNU social, version 2.0.2-dev, available under the GNU Affero General Public License.
All GNU social JP content and data are available under the Creative Commons Attribution 3.0 license.