Which layer in the three-tier model should the redistribution of routing protocols be performed?

The distribution layer is where redistribution of routing protocols should be performed. It should never be performed at the core or access layer. The core layer is where basic routing and switching is performed without slowing down any of the backbone communications. The access layer is where clients and end-user devices are supplied with network connectivity, allowing them to 'access' the network. Routing layer is not terminology used to describe one of the three layers in the Cisco three-tier design model.