# Opportunities and Challenges for Error Correction Scheme for Wireless Body Area Network--A Survey
## 6 Future Research Challenges and Opportunities  
In our view, the ECS should be dynamic, so that it should able to handle a variety of computational complexity, energy-constrained nature of nodes, and different types of communication channels exist in WBAN. The future ECS should exploit those node constraints and the possible communication channels during ECS design and implementation. There are three types of nodes (refer to Figure 4) and computational complexity and energy-constraints of node depends on the type of node. Implant nodes are battery operated, and thus there are strict computational limitations and energy-constrained requirements at implant nodes. However, body surface (wearable devices) and external (mobile or medical devices) nodes are using a rechargeable battery or power supplied at these nodes. Therefore, there is a fewer computational and energy-constraints requirement at these nodes when compared to implant nodes. However, the literature review in Section 5 indicates that previous works were lacking in using these factors during the design of ECS. Therefore, the ECS design and implementation for WBAN should consider those computational and energy-constrained at nodes during the design.  
The suitability of ECS for any communication system depends on the type of communication channel that exist on the communication system. In WBAN, several types of communication channels exist and variation of path loss varies significantly [32; 61]. Therefore, a dynamic ECS should be considered for WBAN to support a variety of channels and nodes that exist in WBAN. The dynamic ECS should able to use multiple ECS techniques in WBAN to handle varieties of QoS requirements, latency requirements, and several type of nodes and channels. Error correction codes and techniques should vary according to scenarios and channel models (refer to Table 3).  
In our view, the following research areas needs to be explored to design efficient ECS design for WBAN:  
* To support variety of nodes, channels, and QoS requirements in WBAN, are dynamic ECS design and implementation based on the software-defined radio suitable for WBAN as introduced for wireless sensor network in [62; 63; 64; 65]?
* The overall efficiency of ECS for WBAN depends on interferences from other WBANs and other existing systems, such as Wi-Fi and WLAN. Further research is expected to analyse the efficiency of WBAN in practical and real-life settings rather than isolated settings, as considered in previous research works.
* A very limited research work is conducted when considering two hop WBAN. One open area of the research is to analyse the consequence, significance, and complication on ECS design when considering two hop in WBAN.
* Does treating the forward link (for example, implant node to surface node) and reverse link (for example, surface node to implant node) differently (similar to mobile communication uplink and downlink) facilitate the innovative design of ECS of WBAN?
* Most of the proposed ECS designs are based on RF communication channels. Does the HBC technique improve or aid on design of efficient ECS for WBAN? This research area, however, significantly differs from the ECS design that we discussed in this paper.
* Most of proposed research works on ECS design for WBAN are based on RF communication channels. Is the optical communication technique, as discussed in [65], appropriate to improve or aid in design of efficient ECS for WBAN specifically implant to implant and implant to wearable device? This research area, however, significantly differs from the ECS design that we discussed in this paper.
* One of the greatest challenges in ECS design on WBAN is to verify the design and expected outcome. Therefore, the creation of simulation settings or tools that resembles the real human bodies is another challenge and would be another research area to explore.