## 3 Background
### Dew Computing  
Dew computing provides a new way for end users (dew users) to connect to cloud-based content without relying on the Internet backhaul [65]. It enables an exciting idea where a dew user can access cloud-based data using their own dew device without requiring minimal intervention from the Internet connection. Dew users can access the same content as a local copy of the cloud content [66; 67]. Once the Internet connection is restored, the changes are homogenized between the local and cloud content. This minimizes the dependency that is on the cloud, where an end user needs an Internet connection every time they want to access the cloud data. Actually, dew computing aims to solve the problems of offline access to data in the existing cloud computing paradigm [68]. Traditional cloud content and configurations are far from user self-control, as such services are provided exclusively at the enterprise level. Dew computing enables users to match endpoint capabilities with cloud services in a more reliable approach [69]. It depends on two aspects: (i) independence: a local dew device can operate independently of cloud services, and (ii) collaboration: a local dew device can communicate with cloud services when Internet connectivity is available, or when synchronization is desired. A dew virtual machine (DVM) is required on the user's dew device, which can take the help of a dew server, a data analytics server, and a dew device decision-making approach [70]. Dew computing can provide multiple services that are equivalent to cloud computing, such as data in dew, platform in dew, infrastructure in dew, web in dew, software in dew, storage in dew, and database in dew [71]. Studies show that dew computing-assisted drones [72] and a federated learning-based blockchain can be useful in IoT-aware drone employments [73].  
The main advantages of dew computing over Cloud, Fog, or Edge computing paradigms can be summarized as follows: (i) negligible latency, (ii) negligible jittering effects, (iii) highly location-aware behavior, (iv) highly distributed geolocated services, (v) very low probability of data redirection attacks, (vi) targets mobile users, (vii) requires limited resources or hardware capacity, (viii) very high-quality user experience, (ix) very low Internet dependency, (x) high delay tolerance, and (xi) very high computing power [74; 75].  
The dew computing paradigm is seen as an extension of the cloud computing scenario, but at the extreme edge of the network, the end users can directly access the Internet [76]. It follows a strict computing hierarchy when it cannot provide the required services to the end users. A dew image for the user-owned cloud repository can be used in the user-owned-dew system [77]. Therefore, synchronization plays an important role in dew computing. Process synchronization with a timestamp can be very useful for dew computing users. The functions of data replication and distribution-oriented transparency can be easily complemented by Internet access to dew computing data. In case of local data loss, there is a great chance to recover the same data from the cloud storage. In addition, rule-based data collection, scalability, and high reliability are important aspects of dew computing that provide a minimalist approach to the Internet backhaul, so that the user experience can be greatly improved [78]. Dew data rental services can be offered between dew devices that are in close proximity, allowing a dew user to access Internet data even if their personal Internet data is unavailable or restricted for some reason. In this way, dew computing can serve as a hotspot network entity.