Centralized Dynamic Host Configuration Protocol and Relay Agent for Smart Wireless Router

Serving a Dynamic Host Configuration Protocol (DHCP) request with some additional services package may cause a conventional wireless router consumes more memory resources. High memory usage would break the DHCP request process if the wireless router becomes busy. In this paper, the centralized DHCP servers is proposed to overcome this situation. In term of Cisco product there is Wireless LAN Controller that can solve that situation. In this research, we suggest an open source solution for this situation. The original master and backup algorithm are modified to reserve DHCP request. DHCP master server serves many connected network under the main router. The modification of original master and backup algorithm is located in resource allocation calculation in the main router. Computer agent checks the memory of the main router to decide a diversion of DHCP pool to the backup router. Run test results show that the proposed method has an acceptable lease time. It can handle 254 DHCP requests within only 0.6 seconds longer than the conventional method. Further, the number of client that could be reserved by the proposed method is better than the method used in OpenWRT router, which is about 100 more clients successfully receive their IP.