In Cisco's three-tier architecture, the links between the distribution layer switches indicate what kind of topology?

The distribution layer is a partial-mesh topology. Links between the distribution switches and core switches are multihomed to each device for redundancy. Also, the links between the distribution switches and access switches are multihomed to each device for redundancy. Although this might seem to be a full-mesh topology, the distribution switches are not connected to each other. A full-mesh topology can often be found between the distribution and core layers. The core layer uses a star topology in a collapsed core design to connect lower layer switches. The ring topology is a legacy LAN topology and is often used in WAN communications.