A method for handling incoming and outgoing data packets in one or more routers, the method comprising: receiving, by a first router, an incoming data packet from a wide area network, the incoming data packet having a first destination IP address as a destination IP address of the incoming data packet, the first destination IP address specifying a computing system on a local area network; receiving, by the first router, an outgoing data packet from the local area network, the outgoing data packet having a second destination IP address as a destination IP address of the outgoing data packet, the second destination IP address specifying a computing system over the wide area network; diverting, by the first router, the incoming data packet and the outgoing data packet to a performance enhancing proxy network device coupled in parallel to the first router, by matching IP addresses of incoming data packets and outgoing data packets to one or more policy based routing rules of a set of rules (140, 145) while preserving the first destination IP address as the destination IP address of the incoming data packet and the second destination IP address as the destination IP address of the outgoing data packet, the one or more policy based routing rules identifying the IP address of the network device; processing, by the performance enhancing proxy network device, the diverted data packets while preserving the first destination IP address as the destination IP address of the incoming data packet and the second destination IP address as the destination IP address of the outgoing data packet; transmitting, by the performance enhancing proxy network device, the processed incoming data packet and outgoing data packet to one of the first router and an optional second router to which the performance enhancing proxy network device is coupled in parallel, the processed incoming data packet having the first destination IP address as the destination IP address of the incoming data packet and the processed outgoing data packet having the second destination IP address as the destination IP address of the outgoing data packet receiving, by the one of the first and optional second routers, the processed incoming data packet having the first destination IP address as the destination IP address of the incoming data packet and the processed outgoing data packet having the second destination IP address as the destination IP address of the outgoing data packet; and delivering, by the one of the first and optional second routers, the processed incoming data packet to the computing system on the local area network identified by the first destination IP address and the processed outgoing data packet to the computing system over the wide area network identified by the second destination IP address. receiving, by a first router, an incoming data packet from a wide area network, the incoming data packet having a first destination IP address as a destination IP address of the incoming data packet, the first destination IP address specifying a computing system on a local area network; receiving, by the first router, an outgoing data packet from the local area network, the outgoing data packet having a second destination IP address as a destination IP address of the outgoing data packet, the second destination IP address specifying a computing system over the wide area network; diverting, by the first router, the incoming data packet and the outgoing data packet to a performance enhancing proxy network device coupled in parallel to the first router, by matching IP addresses of incoming data packets and outgoing data packets to one or more policy based routing rules of a set of rules (140, 145) while preserving the first destination IP address as the destination IP address of the incoming data packet and the second destination IP address as the destination IP address of the outgoing data packet, the one or more policy based routing rules identifying the IP address of the network device; processing, by the performance enhancing proxy network device, the diverted data packets while preserving the first destination IP address as the destination IP address of the incoming data packet and the second destination IP address as the destination IP address of the outgoing data packet; transmitting, by the performance enhancing proxy network device, the processed incoming data packet and outgoing data packet to one of the first router and an optional second router to which the performance enhancing proxy network device is coupled in parallel, the processed incoming data packet having the first destination IP address as the destination IP address of the incoming data packet and the processed outgoing data packet having the second destination IP address as the destination IP address of the outgoing data packet receiving, by the one of the first and optional second routers, the processed incoming data packet having the first destination IP address as the destination IP address of the incoming data packet and the processed outgoing data packet having the second destination IP address as the destination IP address of the outgoing data packet; and delivering, by the one of the first and optional second routers, the processed incoming data packet to the computing system on the local area network identified by the first destination IP address and the processed outgoing data packet to the computing system over the wide area network identified by the second destination IP address.