Wearable Wireless Networks for Internet of Humans: Trends and Challenges
Received Date: Aug 28, 2015 / Accepted Date: Sep 02, 2015 / Published Date: Sep 04, 2015
Interconnected internet of humans (IoH) is a new paradigm in which wearable wireless networks (WWN) are emerging as a key enabling technology. WWN is revolutionizing health-care, sports and fitness, rescue and emergency management, augmented reality, fashion, and many other applications . Wearable wireless networks composed of various types of devices such as sensors, actuator, coordinators, and gateways etc., to realize on-body, body-to-body (B2B) and off-body wireless communication as shown in Figure 1. However, often these devices are severely constrained due to ultra-low power consumption, miniaturization, low processing and storage capabilities as well as low delay requirements, consequently, the reliability and quality-of-service of above mentioned applications are very challenging.
IEEE 802.15.6 standard  provides great flexibility, features and WWN-specific provisions which are necessary to be exploited in the future applications and products. In terms of maximum achievable throughput at narrowband, IEEE 802.15.6 standard can reach up to 680 Kb/s, while operating at maximum frequency and highest modulations order by considering all the overheads of the MAC and PHY layers . This impose limits to the use of IEEE 802.15.6 standard in emerging applications such as augmented reality where transmission of high rate audio and video are necessary. However, since IEEE 802.15.6 standard provides ultra-low power consumption for both invasive and non-invasive devices and with the key security features. The great flexibility on the usage of multiple options at the PHY (i.e., human body communication, narrow band, and ultra-wideband) and at the MAC layer (scheduled access, beacon enabled/disabled, CSMA/CA, polling and posting) as shown in Figure 2. All these factors make the IEEE 802.15.6 standard as a viable option for WWN. This short communication is focused on the important cross-layers perspectives and challenges addressed by WWN and their potential solutions.
Typically, application layer specify the requirements of the given product or solutions and based on those requirements rest of the protocol stack is designed. In WWN, there are number of applications (as explained earlier), require unique and different functionalities, for example, the application requirements of health monitoring of athletes is very different than the chronic or elderly patients. Based on the specific applications, different types of sensors can be selected, and the number of required nodes can be tuned since these factors have direct implications on the network layer. The data rates requirements of each sensor will configure the MAC layer parameters. Therefore, based on the specific application, fine tuning and design can be achieved.
At the network layer, there are number of important questions, for example, which routing mechanisms (i.e., mobile ad-hoc networks-based such as reactive or proactive, data-centric and geographical locations based routing) are most suited for body-tobody communication?, which standard or technology (such as WiFi, WSN, Bluetooth or WBAN) are appropriate for WWN?. To address these questions, one of our recent studies , reflect that both WiFi and WBAN technologies are most effective for B2B, in particular WiFi with geographical based routing approach is the most effective for the higher packet reception ratio and lower energy consumption. These finding are true provided the location information is available, otherwise, WBAN technology with gradient based routing is the best alternate to satisfy reliability constraints. Concerning the data disseminating approaches using WBAN technology for body-to-body communication in WWN, recent study shows that the distributed mechanism is more efficient than cluster-based for the packet delays, whereas, for the successful packet reception ratio, clustered approach is much better than the distributed .
In B2B communication, both co-channel and adjacent channel interference can disrupt the communication. In this regard, channel hopping and time shared coexistence schemes are very effective . Although, time shared is more costly in terms of delay, but if the application is not delay constrained it can be considered. At the medium access control (MAC) layer, scheduled access is a viable option for the on-body communication, whereas in body-to-body communication since there are multiple coordinators, it becomes very complex to manage the superframes especially which coordinator to be selected as the leader that can control the beacon transmissions. In this regards multiple super frames can be used. On the other hand, CSMA/CA as a channel access technique is much simpler and can be implemented in a distributed fashion. It also provides much lower delay in comparison to scheduled access method.
Channel modeling is very active topic of research in both on-body and body-to-body communication [7-9]. Recently, body-to-body channel characterization and stochastic model is discussed , and the impact of short-term fading is analyzed in B2B communication. For effective on-body and body-to-body communication, accurate radio link and mobility modeling is vital. Most of the WWN nodes constantly vary over space and time which degrades the packet reception performance due to body shadowing and fading effects. Therefore, it is important to consider in the system design such models which take into account these factors and their effects. One of the options is to use deterministic approach for accurately estimating the pathloss and hence channel models can be much more accurate . The physical layer of the emerging WWN applications are often required to be multistandard compliant, typically, the on-body coordinator is selected for this purpose which can reach-out to the farthest nodes using powerful transceivers such as WiFi . This is important in rescue and critical applications where end to end network connectivity is required.
Finally, IEEE 802.15.6 standard compliant radio transceivers are not yet commercially available which limits the product development and prototyping of WWN using IEEE 802.15.6 standard. However, efforts are such as Rahman, Lee et al. [12,13], but fully functional compliant radios are expected to be available by end of 2015. Another open research challenges include the privacy and security. In this regards, initial studies such as Cornelius, Toorani et al. [14,15], address the security venerability and personalized unobtrusive interactions solutions. However, the vision of secure WWN is still to be achieved where the devices would discover and recognize the authentic users while establishing a secure communication channel.
This publication was made possible by NPRP grant # [6-1508-2-616] from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.
- Alam MM, Hamida EB (2014) Surveying Wearable Human Assistive Technology for Life and Safety Critical Applications: Standards, Challenges and Opportunities. Sensors 5: 9153-9209.
- IEEE (2012) Standard for Local and metropolitan area networks - Part 15.6: Wireless Body Area Networks.
- Alam MM, Hamida EB (2015) Strategies for Optimal MAC Parameters Tuning in IEEE 802.15.6 Wearable Wireless Sensor Networks. Journal of Medical Systems30:106.
- Arbia DB, Alam MM, Attia R, Hamida EB (2015) Behavior of Wireless Body-to-Body Networks Routing Strategies for Public Protection and Disaster Relief. 11th IEEE WiMob Conference, First International Workshop on Advances in Body-Centric Wireless Communications and Networks and Their Applications (BCWNets 2015),Abu Dhabi
- Arbia DB, Alam MM, Attia R, Hamida EB (2015) Data Dissemination Strategies for Emerging Wireless Body-to-Body Networks based Internet of Humans. 11th IEEE WiMob Conference, Second International Workshop on Emergency Networks for Public Protection and Disaster Relief EN4PPDR,Abu Dhabi.
- Alam MM, Hamida EB (2015) Interference mitigation and coexistence strategies in IEEE 802.15.6 based wearable body-to-body networks.10th International Conference on Cognitive Radio Oriented Wireless Networks (CROWNCOM), Doha, Qatar.
- Mani F, D'Errico R, (2015) Short Term Fading Spatial Dependence in Indoor Body-to-Body Communications.IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (IEEE PIMRC ), China.
- IEEE PIMRC
- Khan MM, Abbasi QH, Alomainy A, Hao Y(2011) Study of line of sight and none line of sight ultra wideband off-body radio propagation for body centric wireless communications in indoor.IEEE European Conference on Antennas and Propagation110-114.
- D’Errico R, Ouvry L (2009) Time-variant BAN channel characterization. IEEE Personal, Indoor and Mobile Radio Communications (IEEE PIMRC) 3000-3004)
- Alam MM, Hamida EB, (2014) Towards Accurate Mobility and Radio Link Modeling for IEEE 802.15.6 Wearable Body Sensor Networks. 7th IEEE International Workshop on Selected Topics in Wireless and Mobile computing, Cyprus.
- Alam MM, Hamida EB (2015) Research Trends in Multi-Standard Device-to-Device Communication in Wearable Wireless Networks.10th International Conference on Cognitive Radio Oriented Wireless Networks (CROWNCOM), Workshop on Cognitive Radio for 5G Networks, Doha, Qatar.
- Rahman M, Elbadry M, Harjani R (2015) An IEEE 802.15.6 standard compliant 2.5 nj/bit multiband wban transmitter using phase multiplexing and injection locking50: 1126-1136
- Cornelius C, Peterson R, Skinner J, Halter R, Kotz D (2014) A wearable system that knows who wears it. The 12thInternational Conference on Mobile Systems, Applications, and Services (MobiSys), pp. 55-67.
- Toorani M (2015) On vulnerabilities of the security association in the IEEE 802.15.6 standard. Financial Cryptography and Data Security (FC’15) Workshops - 1st Workshop on Wearable Security and Privacy (Wearable’15).
Citation: Mahtab Alam M, Ben Hamida E (2015) Wearable Wireless Networks for Internet of Humans: Trends and Challenges. J Telecommun Syst Manage 4: e115. Doi: 10.4172/2167-0919.1000e115
Copyright: ©2015 Mahtab Alam M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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