## 1 Introduction  
In this emerging age of technology, the Internet of Things (IoT) has a large role in the future of smart cities and is expected to bring a significant amount of cash flowing through the market in the upcoming years. IoT is expected to be found in many fields such as smart business, building, and home automation, healthcare, and the automotive industry [1]. IoT relies on Service-Oriented Architecture (SOA), a basic independent component for protocol communication over the Internet or a network (such as HTTP), and Web Services (WS), a standard of SOA for implementing dynamic and supplying business processes.  
WS can act as a connection between IoT devices and data storage. WS are used as a medium to process data and are required for storing the processed data into the respective database. WS are now being used by several industries to share information for functions across platforms [2]. Instead of invoking several WS to complete the business processes for different functional requirements such as'registration', 'login','sending email', 'chat', etc., Web Service Composition (WSC) was developed. WSC is the coordination or combination of several WS into a single web service. WSC will be the intermediate medium to process and store data dynamically; thus, research must consider several types of composition methods.  
Of late, integrating WSC into the IoT devices is being perceived as an emerging paradigm also known as the IoT Service Composition (IoTSC). With the idea of an IoT device serving as a cloud database, it can be inferred that IoTSC may help save resources and costs; however, overheating of IoT devices is a major issue because it can lead to device failure. One of the key reasons for overheating is that so many processes are performed by the IoT devices, 24 h, 7 days a week. Furthermore, according to [3], most approaches do not satisfy certain required criteria and ignore the fundamental aspect of IoT, especially on the real-time constraint, monitoring, and fault tolerance. This is made worse due to limited evidence on the lack of monitoring on temperature, energy [4], and power consumed that overheat the devices. Thus, in this research, several types of composition methods are considered to tackle this major issue.  
As a result of the high computation time in selecting WS, the time taken to complete the WSC had increased, especially in a large-scale repository. As mentioned by [5], the number of services had been increasing, but the existing solutions were insufficient to solve the large-scale problems. Thus, we can summarize that poor performance during service selection in large-scale service repositories and selecting the correct service to avoid user dissatisfaction were among the main issues. We hereby put this research forward with the following objectives:  
1. To reduce computation time in selecting WS;  
To propose a hybrid model for IoT devices to reduce the execution time on selecting the service from a large-scale cloud-based web service repository for DWSC. This model to be proposed is to increase the performance, which directly indicates the reduction in computational time on large-scale DWSC. This proposed model can be implemented into IoT devices. Hence, the process and overheating issue may be reduced.
2. To select the correct service in selecting WS.  
To select the correct service based on user requirements for DWSC. This may be able to improve user satisfaction and maintain the SLA.