question: the number of connections in ceph

Hi , I want to know the number of connections in CEPH. I think the connection is mainly OSD connection. Is the following statement correct? Each OSD is connected with other OSDs, and there may be more than one connection between two OSDs. If there is only one connection per OSD, the number of the connection is N(N-1)/2,. If there are k connections per OSD, the number of the connection is kN(N-1)/2. Thanks for your help. Best regards. Congmin Yin