# A Proposal for IoT Dynamic Routes Selection Based on Contextual Information
## 1 Introduction  
Internet of Things (IoT) is referred to as the interconnection of physical objects that have an IP address for Internet connectivity. A huge number of smart devices are interconnected to the Internet today. There is an exponential growth in the number of smart devices interconnected through the mobile Internet [1]. IoT can be used in architectures, such as the proposal presented in [2], which represents an architecture for two-way communication between smart utility meters and utility companies. Is a wireless sensor network that provides communication for metering devices in the neighborhood area of a smart grid. Another point that is addressed in IoT is mobility, which is a fundamental issue related to the detection of mobile nodes movement and the provision of better links through an efficient routes selection [3]. Many contributions are evidenced in the literature in the IoT topic, such as the following: study of mechanisms for the topology control [4], location and mobility in Wireless Sensor Networks (WSNs) [5] and routing based on objective functions [6; 7; 8]. It is considered also as pervasive presence of devices variety, such as sensors, Radio Frequency Identification (RFID) tags and smartphones, among other devices which can interact with each other for a common purpose [9]. In a scenario of IoT, plurality is increasing and forecasts indicate that over 40 billion devices will be connected until 2020 [2], allowing the emergence of an infinity of new applications, such as for smart cities, healthcare, smart houses, industry, agriculture, etc. Among the most promising technologies for the IoT paradigm, RFID and Wireless Sensor Networks (WSNs) are the most common and appropriate [9; 10]. WSNs have limitations on the identification of a person or object in some types of applications. However, unlike WSNs, RFID systems are unable to sense data from the place in which they are used, such as humidity, temperature and pressure that are provided by sensors. This is an indication that IoT, by means of the integration between the RFID and WSN technologies, maximizes the benefits, thus opening up new perspectives for applications that consider context information, such as temperature monitoring in remote areas and air quality of a specific city or region, vehicle control flows, among others. The context usually refers to the collected information regarding a given situation and may include also the location. Moreover, it can also cover different information used to characterize entities involved in the interaction between the user and the application. According to [11], context-sensitive systems are able to adapt their behavior to current conditions with no explicit intervention from users. In IoT, an amount of information, such as features of the device itself, of the environment which surrounds it and its capacity, can be used as a source of context information. Many papers available in literature are converging in efforts to address issues involving context sensitivity in IoT, especially at the route selection stage [12; 13; 14]. At this stage, devices (which have resource constraints) process contextual information locally in order to select the path that best meets the requirements of a given application. Such feature requires context-sensitive routing protocols for the fulfillment of a number of challenges during messages exchange, including shorter delay, greater reliability on data transmission and minimal power consumption. Based on these challenges, this paper proposes an improvement for the RPL protocol [15] that considers the creation of four new Objective Functions (OFs) that enable the devices to select the parent node (default route) based on the context information obtained from the application. The use of proposed OFs occurs in the process of establishing routes in order to meet the context of the applications.