interfaces on the computing devices e g vm servers a source of complication may exist in some embodiments where several security devices located on different computing devices e g vm servers share the same port pair on a hardware ips device fig1 illustrates a system configuration of some embodiments that includes several vm servers sharing the same port pair of a hardware ips device as shown the system of fig1 includes ips 101 switch 102 and vm servers 103 105 vmware esx servers are shown throughout this application as vm servers for exemplary purposes however other types of vm servers may be used as well a problem of the system configuration shown in fig1 is flooding when a switch receives a packet if the switch has not learned the destination media access control mac address the switch floods the packets by sending the packet to all the devices connected to the switch fig2 illustrates flooding in the system configuration of fig1 here switch 202 has not learned the destination mac address of a packet sent from vm server 203 thus when switch 202 receives the packet from vm server 203 switch 202 sends the packet to all the other devices connected to switch 202 which are ips 201 vm server 204 and vm server 205 a problem with flooding is that it.