When a session is handed off from one access point to another access point using the same technology, the handover can usually be performed within that wireless technology itself without involving MIHF or IP. For instance a VoIP call from a Wi-Fi handset to a Wi-Fi access point can be handed over to another Wi-Fi access point within the same network, e.g. a corporate network, using Wi-Fi standards such as 802.11f and 802.11r. However, if the handover is from a Wi-Fi access point in a corporate network to a public Wi-Fi hotspot, then MIH is required, since the two access points cannot communicate with each other at the link layer, and are, in general, on different IP subnets.