A mechanism is disclosed that enables layer two host addresses (e.g. a MAC addresses) to be shielded from a network. In one implementation, the mechanism updates each packet sent by the hosts into the network to indicate that the source layer two (L2) address for that packet is a shared L2 address instead of the actual L2 address of the sending host. By doing so, the mechanism exposes only the shared L2 address to the network, and shields the actual L2 addresses of the hosts from the network. The effect of this is that the switches in the network will need to store only the shared L2 address in their forwarding tables, not the actual L2 addresses of the hosts. By reducing the number of L2 addresses that need to be stored in the forwarding tables of the switches, the mechanism improves the scalability of the network.