A first network device comprising: tangible computer readable storage media configured to store traffic, instructions for a lookup engine, a map manager, a traffic forwarder, and a map; a processor configured to: store data in the tangible computer readable storage media; and execute the instructions for the lookup engine; a first address input configured to receive outbound traffic from a first computing device at a first address and destined for a second computing device at a second address, the traffic comprising a data packet and the second address of the second computing device; the map manager configured to generate, responsive to receiving the outbound traffic from the first computing device destined for the second computing device, the map stored in the tangible computer readable storage media, the map comprising a rule associating the first address of the first computing device and the second address of the second computing device; the traffic forwarder configured to forward the outbound traffic to the second computing device; a second address input configured to receive return traffic directed to the first computing device; the lookup engine, executable by the processor, comprising instructions to cause the processor to check the map to determine whether the map comprises a rule associating a source address of the return traffic and the first address of the first computing device, responsive to a determination that the map comprises this rule, the instructions in the lookup engine cause the processor to forward the return traffic to the first computing device, responsive to a determination that the map does not comprises this rule, the instructions cause the processor to send a query to a second network device, the query asking whether the second network device comprises a rule associating the source address of the return traffic and the first address of the first computing device; a network device input configured to receive a response to the query; and a map updater configured to update the map based on the response from the query. tangible computer readable storage media configured to store traffic, instructions for a lookup engine, a map manager, a traffic forwarder, and a map; a processor configured to: store data in the tangible computer readable storage media; and execute the instructions for the lookup engine; store data in the tangible computer readable storage media; and execute the instructions for the lookup engine; a first address input configured to receive outbound traffic from a first computing device at a first address and destined for a second computing device at a second address, the traffic comprising a data packet and the second address of the second computing device; the map manager configured to generate, responsive to receiving the outbound traffic from the first computing device destined for the second computing device, the map stored in the tangible computer readable storage media, the map comprising a rule associating the first address of the first computing device and the second address of the second computing device; the traffic forwarder configured to forward the outbound traffic to the second computing device; a second address input configured to receive return traffic directed to the first computing device; the lookup engine, executable by the processor, comprising instructions to cause the processor to check the map to determine whether the map comprises a rule associating a source address of the return traffic and the first address of the first computing device, responsive to a determination that the map comprises this rule, the instructions in the lookup engine cause the processor to forward the return traffic to the first computing device, responsive to a determination that the map does not comprises this rule, the instructions cause the processor to send a query to a second network device, the query asking whether the second network device comprises a rule associating the source address of the return traffic and the first address of the first computing device; responsive to a determination that the map comprises this rule, the instructions in the lookup engine cause the processor to forward the return traffic to the first computing device, responsive to a determination that the map does not comprises this rule, the instructions cause the processor to send a query to a second network device, the query asking whether the second network device comprises a rule associating the source address of the return traffic and the first address of the first computing device; a network device input configured to receive a response to the query; and a map updater configured to update the map based on the response from the query.