A switch adapted to forward traffic to a plurality of end devices (142, 148), comprising: a processor; a fabric switch module adapted to maintain a membership in an extended network of interconnected switches comprising a first network of interconnected switches (122, 124, 126, 128) and a second network of interconnected switches (132, 134, 136, 138), wherein the first network of interconnected switches is identified by a first identifier and the second network of interconnected switches is identified by a second identifier; and a learning module adapted to: identify from a payload of a notification message from the second network of interconnected switches, a media access control, MAC, address of at least one of the plurality of end devices (142, 148) learned at a switch in the second network of interconnected switches, characterised in that: the header of the notification message includes an Internet Protocol, IP, address indicating the second network of interconnected switches as a source IP address, wherein the IP address is a floating IP address and associated with a plurality of member switches of the second network of interconnected switches; and store a mapping between the identified MAC address learned at the switch in the second network of interconnected switches and the IP address in a local MAC table; and a forwarding module adapted to encapsulate (332, 336) a packet comprising the MAC address with a tunnel encapsulation header, wherein the encapsulation header includes the IP address as a destination IP address. a processor; a fabric switch module adapted to maintain a membership in an extended network of interconnected switches comprising a first network of interconnected switches (122, 124, 126, 128) and a second network of interconnected switches (132, 134, 136, 138), wherein the first network of interconnected switches is identified by a first identifier and the second network of interconnected switches is identified by a second identifier; and a learning module adapted to: identify from a payload of a notification message from the second network of interconnected switches, a media access control, MAC, address of at least one of the plurality of end devices (142, 148) learned at a switch in the second network of interconnected switches, characterised in that: the header of the notification message includes an Internet Protocol, IP, address indicating the second network of interconnected switches as a source IP address, wherein the IP address is a floating IP address and associated with a plurality of member switches of the second network of interconnected switches; and store a mapping between the identified MAC address learned at the switch in the second network of interconnected switches and the IP address in a local MAC table; and a forwarding module adapted to encapsulate (332, 336) a packet comprising the MAC address with a tunnel encapsulation header, wherein the encapsulation header includes the IP address as a destination IP address. identify from a payload of a notification message from the second network of interconnected switches, a media access control, MAC, address of at least one of the plurality of end devices (142, 148) learned at a switch in the second network of interconnected switches, characterised in that: the header of the notification message includes an Internet Protocol, IP, address indicating the second network of interconnected switches as a source IP address, wherein the IP address is a floating IP address and associated with a plurality of member switches of the second network of interconnected switches; and store a mapping between the identified MAC address learned at the switch in the second network of interconnected switches and the IP address in a local MAC table; and the header of the notification message includes an Internet Protocol, IP, address indicating the second network of interconnected switches as a source IP address, wherein the IP address is a floating IP address and associated with a plurality of member switches of the second network of interconnected switches; and store a mapping between the identified MAC address learned at the switch in the second network of interconnected switches and the IP address in a local MAC table; and a forwarding module adapted to encapsulate (332, 336) a packet comprising the MAC address with a tunnel encapsulation header, wherein the encapsulation header includes the IP address as a destination IP address.