Which wireless topology supports roaming from one access point to another?

ESS (Extended Service Set) is a wireless topology where multiple access points are connected to the same wired network and share the same SSID, enabling seamless roaming. IBSS (Independent Basic Service Set), also called ad hoc mode, is a peer-to-peer network between wireless devices without an access point. Ad hoc (C) is the same as IBSS. Only ESS (A) supports roaming between access points because stations can move between APs while maintaining connectivity to the same network.