Methods and apparatuses for acquisition of an address resolution protocol (ARP)/IPv6 Neighbour cache at a user plane function (UPF) entity without performing deep packet inspection for every packet that traverses a network. The ARP broadcast/ICMPv6 Neighbour Solicitation multicast from any Ethernet client (a user equipment (UE) or clients behind the UE or clients in a data network (DN)) is responded to by the UPF entity itself, by looking up the ARP/IPv6 Neighbour cache built in the UPF entity, irrespective of whether the UPF entity acts as the core Ethernet switch or whether the core Ethernet switch is in the DN. The solution is simplified to always intercept ARP at the UPF entity and respond to it based on a local ARP/IPv6 Neighbour cache.