## 1 Introduction
The survey presented by [30] focuses on the routing protocols developed for wireless body sensor networks (WBSNs), a subset of the WSNs responsible for monitoring the vital signs of patients and accordingly routing these data towards a sink. According to [30, 31], routing algorithms for WBSNs need to address some specific issues, such as: frequent topology partition due to body postural movements; devices with very limited resources in order to be attached to a human body; new nodes must be able to enter the network quickly and easily; integrity of the data and patient privacy issues are critical; and the networks are often linked to external healthcare systems through the Internet. Those issues are not as important or even do not exist in IWSN, thus those algorithms cannot viably be implemented in a WirelessHART system without further adaptation and, thus, are not suitable for the scope of the present paper. The work in [32] presents a survey in order to provide insight into routing protocols designed specifically for large-scale generic WSNs. As examples for large-scale WSN applications, we have intrusion detection, weather monitoring and disaster monitoring. Finally, the survey presented by [33] has the objective of presenting the state-of-the-art of duty-cycled wireless sensor networks. The author defines duty-cycled networks as those in which the nodes turn off their radios when no sensing or communication tasks are required and go to sleep, to wake up later in order to sample the environment and check for any channel activity. For scheduling, the literature has fewer surveys than for routing. The work in [34] describes the main WSN properties that are important for the design of a time division multiple access (TDMA) protocol and also outlines the main protocols available for WSN. The comparison of the protocols is based on latency, channel interference, synchronization time needed, communication patterns supported by the algorithm and the adaptability to changes in the topology. A survey of bandwidth resource allocation and scheduling is presented by [35], addressing heuristics for slot time allocation on multiple hops. Finally, [36] presents a survey that analyzes algorithms to support the allocation of a guaranteed time slot (GTS; see [37]) to the devices during the contention-free period part of the superframe [38] in IEEE 802.15.4-based networks. Although this is a very rich environment, none of the aforementioned surveys are technology focused, providing an overview for generic WSNs. In order to attend to users who have already chosen the WirelessHART technology, we will provide an analysis and comparison of the newest routing and scheduling protocols for this technology. The remainder of this paper is organized as follows. In Section 2, we present a brief overview of the WirelessHART technology. Sections 2.1 and 2.2 emphasize the TDMA technique, used in the MAC layer, and the IEEE 802.15.4 physical layer structures, common to the other current IWSN technologies (ISA100.11a [39] WIA-PA [40]). As the main focus of the present paper, the scheduling and routing of the WirelessHART are respectively detailed in Sections 2.2.1 and 2.2.2. Section 3 presents a comparative study of the state-of-the-art of routing algorithms. A similar description and comparison is presented in Section 4 for the state-of-the-art WirelessHART scheduling algorithms. In Section 5, we will present the main WirelessHART simulators available for algorithm validation purposes. Finally, some concluding remarks are provided in Section 6.