# Lightweight Integrity Preserving Scheme for Secure Data Exchange in Cloud-Based IoT Systems
## 1 Introduction  
The inherent adaptability and instantaneity serve to generate a number of advantages for the IoT. These include reductions in hardship in the regulation of storage, general information accessibility regardless of location, and evasion of capital costs for various items such as hardware, software, and individual upkeep [1]. The IoT-cloud system technology is recognised as being the most modern advancement for the structuring of IT corporations. This is because of its numerous unparalleled benefits such as on-demand self-service, pervasive network accessibility, context-independent asset sharing, quick asset flexibility, employment-based costs, and hazard mitigation [2]. Therefore, the IoT-cloud system has become an innovate system that has exerted crucialeffects in many organizations. This has seen a rise in the adoption of certain IT services by corporations. An important aspect of this change is the fact that information on the cloud is obtained from external sources. As such, both corporations and individual users have the opportunity to upload information on to the IoT-cloud system. Although IoT-cloud-based systems have many attractive features, they generate unique and difficult safeguarding issues for information obtained from external sources. This can be attributed to the fact that IoT-cloud systems are isolated from the regulating companies. Consequently, external information decreases a smart device user's regulation and control of their information. This jeopardises the information stored on these IoT-cloud-based systems in a number of ways. For instance, although this infrastructure has greater influence and dependability compared with individuals' computing technology, individuals continue to encounter various external and internal hazards that might affect the accuracy of the information. This is exampled by the shortages and violations of the safeguarding methods deployed to protect these IoT-cloud systems. In addition, smart device users are unaware of the location of their external information. For instance, financial constraints may make organizations deploy cloud storage space, especially for information that is not frequently accessed [3; 4; 5]. Another challenge is that IoT-cloud systems potentially conceal information misplacement, which may be detrimental to the users. Although outsourcing information to the cloud system has financial benefits in terms of expenses and complications in the lengthy and massive amounts of information storage for smart device users, the honesty and efficient accessibility of this information is not always assured. This negatively affects the effective utilisation of smart device cloud users. There are many conventional cryptographic primitives that can be deployed to safeguard information stored in the cloud. However, these techniques cannot be immediately employed as smart device users do not have absolute control over the storage of their information. In addition, these cryptographic methods may not be appropriate for the computation and storage-limited user devices. Therefore, techniques for the successful confirmation of the validity of external cloud information in the absence of local replications of information have become a serious issue in storing information safely in IoT-cloud systems [6; 7; 8]. The process of downloading information does not represent a feasible method for the confirmation of data integrity. This is due to the high costs associated with I/O and the transfer of files within the network. Additionally, I/O is typically inadequate for identifying information fraud during the process of information retrieval. This is because at this stage, information that has been compromised may no longer be salvaged. Another major issue is the expansive dimensions of external information and smart device users' restrictions regarding asset abilities. As such, confirming the validity of information within the IoT-cloud system can be impractical and cost-ineffective for smart device users [8; 9].