Interconnecting WirelessHART and legacy HART networks

WirelessHART is a novel standardized wireless sensor network protocol for industrial process automation. The WirelessHART protocol is designed with the aim to complement the HART protocol by providing wireless extension to it. However, due to the different physical and data-link layers the two protocols are not directly interoperable. WirelessHART is based on IEEE 802.15.4 mesh networks whereas HART is a 4-20mA analog wired protocol. Keeping in view the huge installations of HART networks throughout the world we feel the need to integrate HART and WirelessHART networks as the WirelessHART standard does not specify the means to securely connect the two networks. In this paper we provide different options to integrate Wire-lessHART and legacy HART networks. We start integrating the two networks using a gateway. However, gateway based integrations are sometimes not feasible and are insecure. The main contribution of this paper is that we provide a novel and comparatively secure solution to interconnect WirelessHART networks with HART networks. We specify and design a new WirelessHART Integrator that extends the capabilities of the WirelessHART adapter and provides integration at the network level rather than at the device level only. We also analyze and compare our solution with gateway and adapter based solutions.