The routing protocol for low power and lossy network (RPL) started to be designed by the ROLL working group of IETF since the year of 2008. Until the RFC6550 was released, this standard with its routing algorithms and four application scenarios, such as home and building automation, industrial control, and urban environment, have been grounded. As a main jigsaw of the paradigm of the Internet of Things (IoT), RPL plays the major role and has become an impressed technical tendency in the field of wireless communication. However, it is still very difficult to find effective approaches to simulate and evaluate RPL's behaviors and other extensions of its applicability, especially in the domain of precision agriculture. Notice that wireless sensor network (WSN) has been deployed a wide variety of wireless sensing devices, and should be one valued supported part of the promising IoT ecosystem. In this paper, first the authors provide a brief presentation of the related protocols including their standardization, the existing implementations, and a group of simulation experiment results obtained from the RPL capable COOJA simulator with its developed modules. Second, the authors then focus on the utilization of this protocol in the agricultural low power and lossy network (A-LLN) area and propose their dedicated instances hybrid network architecture to meet its specific requirements. Moreover, the Web of things (WoT), a trend and new vision of IoT, is appended in the authors' proposal to provide a novel dimension in design of A-LLN since it enables a full interoperability with current web application and higher efficiency of development. As a conclusion, the authors summarized their ongoing work and future solutions of the current technology issues.

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The aim of this paper is to evaluate the real-time performance of our new FF-MAC 'Fast-Forward MAC' protocol through a set of real world experiments. This protocol is proposed as an enhancement of the IEEE 802.15.4 standard for time critical applications. Hence, it is compared with the GTS 'Guaranteed Time Slot' mechanism of this standard. The obtained experimental results by using real world wireless sensor network nodes are proposed as a complement to the simulation results, previously measured in the Network Simulator 2 'NS-2', in order to prove these improvements from a practical point of view. We introduced a new mechanism to the proposed protocol in order to meet the memory constraint. The goal is to protect the time critical data from being dropped when the coordinator queue is full. The obtained results confirm the viability of our protocol and its performances even in a realistic testing environment, which make it applicable in real world applications.