A method performed by an Edge Device, ED, for forwarding a packet, the method comprising: establishing a first Ethernet Virtual Interconnection, EVI, tunnel for bearing Ethernet packets and a first EVI extension tunnel for bearing IP packets, both the first EVI tunnel and the first EVI extension tunnel being connected to a peer ED; receiving an Ethernet packet containing an IP packet; searching a layer 2 forwarding table based on the destination MAC address of the received Ethernet packet, and determining whether to perform layer 3 forwarding based on a layer 2 forwarding item found in the search; upon determining not to perform layer 3 forwarding, sending, through the first EVI tunnel, the Ethernet packet for layer 2 forwarding in an EVI forwarding instance; and upon determining to perform layer 3 forwarding, searching a Forwarding Information Base, FIB, for an FIB entry matching on a destination IP address of the IP packet, wherein the destination IP address is the IP address of a host; in response to finding an FIB entry matching the destination IP address: encapsulating the IP packet into an IP over IP Generic Routing Encapsulation, GRE, packet containing a public layer 2 header and a first EVI extension tunnel header based on encapsulation information of the first EVI extension tunnel, wherein the encapsulation information is comprised in the FIB entry matching the destination IP address; and sending, the IP over IP GRE packet through a public outbound interface of the first EVI extension tunnel, wherein the public outbound interface is comprised in the FIB entry matching the destination IP address; in response to not finding an FIB entry matching the destination IP address, generating an Address Resolution Protocol, ARP, request packet for the MAC address of the host and sending the generated ARP request packet through the first EVI tunnel; and receiving an ARP response packet for the ARP packet through a second EVI tunnel, and creating a new FIB entry in the FIB comprising a sender IP address of the ARP response packet, the encapsulation information of the first EVI extension tunnel, and the public outbound interface of the first EVI extension tunnel, wherein the sender IP address of the ARP response packet is the IP address of the host. establishing a first Ethernet Virtual Interconnection, EVI, tunnel for bearing Ethernet packets and a first EVI extension tunnel for bearing IP packets, both the first EVI tunnel and the first EVI extension tunnel being connected to a peer ED; receiving an Ethernet packet containing an IP packet; searching a layer 2 forwarding table based on the destination MAC address of the received Ethernet packet, and determining whether to perform layer 3 forwarding based on a layer 2 forwarding item found in the search; upon determining not to perform layer 3 forwarding, sending, through the first EVI tunnel, the Ethernet packet for layer 2 forwarding in an EVI forwarding instance; and upon determining to perform layer 3 forwarding, searching a Forwarding Information Base, FIB, for an FIB entry matching on a destination IP address of the IP packet, wherein the destination IP address is the IP address of a host; in response to finding an FIB entry matching the destination IP address: encapsulating the IP packet into an IP over IP Generic Routing Encapsulation, GRE, packet containing a public layer 2 header and a first EVI extension tunnel header based on encapsulation information of the first EVI extension tunnel, wherein the encapsulation information is comprised in the FIB entry matching the destination IP address; and sending, the IP over IP GRE packet through a public outbound interface of the first EVI extension tunnel, wherein the public outbound interface is comprised in the FIB entry matching the destination IP address; encapsulating the IP packet into an IP over IP Generic Routing Encapsulation, GRE, packet containing a public layer 2 header and a first EVI extension tunnel header based on encapsulation information of the first EVI extension tunnel, wherein the encapsulation information is comprised in the FIB entry matching the destination IP address; and sending, the IP over IP GRE packet through a public outbound interface of the first EVI extension tunnel, wherein the public outbound interface is comprised in the FIB entry matching the destination IP address; in response to not finding an FIB entry matching the destination IP address, generating an Address Resolution Protocol, ARP, request packet for the MAC address of the host and sending the generated ARP request packet through the first EVI tunnel; and receiving an ARP response packet for the ARP packet through a second EVI tunnel, and creating a new FIB entry in the FIB comprising a sender IP address of the ARP response packet, the encapsulation information of the first EVI extension tunnel, and the public outbound interface of the first EVI extension tunnel, wherein the sender IP address of the ARP response packet is the IP address of the host.