Academic literature on the topic '6LoWPAN Stacks'

Vast majority of wireless appliances used in household, industry and medical field share the ISM frequency band. These devices need to coexist and thus are challenged to tolerate their mutual interference. One way of dealing with this is by using frequency hopping; where the device changes its radio channel periodically. Consequently, communications will not suffer from the same interference each time; instead, it should be fairer and more stable. This thesis investigates the aforementioned problem in the field of low power wireless sensor networks and Internet of Things where Contiki OS is used. We introduce a low-power pseudo-random frequency-hopping MAC protocol which is specifically characterized as a duty cycled asynchronous sender-initiated LPL style protocol. We illustrate two flavors of the protocol; one that does not use any dedicated channel and another which allows dedicated broadcast channels that can implement frequency-hopping as well. We implement the protocol in C for real hardware and extensively test and evaluate it in a simulated environment which runs Contiki. It proved to work with Contiki's IPv6 stack running RPL (the standardized routing protocol for low power and lossy wireless networks). We compare the performance of the implemented protocol to the singlechannel ContikiMAC with varying levels of interference. Results show a reduction down to 56% less radio-on time (1.50% vs. 3.4%) and 85% less latency (306 ms vs. 2050 ms) in the presence of noise, while keeping a good basecost in noise-free environments with 1.29% radio duty cycle when using 9 channels with no dedicated broadcast channels (vs. 0.80% for single channel) and 252 ms average latency(vs. 235 ms). Moreover, the results show that the multichannel protocol performance metrics converge to almost the same values regardless of the noise level. Therefore, it is recommended  as a good alternative to single channel ContikiMAC in real worlddeployments where noise presence is anticipated.

This thesis deals with the issues 6LoWPAN protokolu and implementation of IPv6 on the specied platform. Introduction thesis deals with the explanation of wireless sensor networks. Next it was descibed 6LoWPAN protocol, which maps IPv6 on standard IEEE 802.15.4. The thesis further concentrates to exploration of possible operation systems, that are designed for sensor networks and then followed by comparison of their characteristics and advantages. The fth chapter is focused on he implementation of the operating system to the sensor node Iris, introduction Iris and with the structure of the operating system Contiki OS. At the end of thesis is description of the implementation of this system in the sensor node Iris.