Abstract
Wireless Sensor Network (WSN) has become very important and are being used widely especially in embedded applications. Normally, these applications require numerous low cost, low power and low data nodes that communicating over multiple hop to cover a large geographical area. Introduction of 6LoWPAN makes it possible for IP address to be assigned on numerous sensor nodes and allow connectivity to Internet. This paper proposes an optimal forwarding routing protocol in 6LoWPAN that gives better performance in term of throughput up to 11% and 43% compared to RIP and greedy forwarding respectively. The forwarding criterion is based on the best optimal forwarding value calculated from link estimation, cost estimation and RSSI characteristics of its neighbors. If transmission failure happened, this routing protocol will provide other candidates of the neighbors node that still have respectable optimal forwarding value as an option.