A Survey on Mobility-Induced Service Migration in the Fog, Edge, and Related Computing Paradigms <s> Demonstrators <s> A recent trend in communication networks---sometimes referred to as fog computing---offers to execute computational tasks close to the access points of the networks. This enables mobile Complex Event Processing (CEP) middlewares to significantly reduce end-to-end latencies and bandwidth usage by migrating operators when event sources and consumers change their location. This demonstration shows the impact of proactive migration strategies on the perceived end user quality in the context of a video monitoring application. <s> BIB001 </s> A Survey on Mobility-Induced Service Migration in the Fog, Edge, and Related Computing Paradigms <s> Demonstrators <s> Geo-distributed Situation Awareness applications are large in scale and are characterized by 24/7 data generation from mobile and stationary sensors (such as cameras and GPS devices); latency-sensitivity for converting sensed data to actionable knowledge; and elastic and bursty needs for computational resources. Fog computing [7] envisions providing computational resources close to the edge of the network, consequently reducing the latency for the sense-process-actuate cycle that exists in these applications. We propose Foglets, a programming infrastructure for the geo-distributed computational continuum represented by fog nodes and the cloud. Foglets provides APIs for a spatio-temporal data abstraction for storing and retrieving application generated data on the local nodes, and primitives for communication among the resources in the computational continuum. Foglets manages the application components on the Fog nodes. Algorithms are presented for launching application components and handling the migration of these components between Fog nodes, based on the mobility pattern of the sensors and the dynamic computational needs of the application. Evaluation results are presented for a Fog network consisting of 16 nodes using a simulated vehicular network as the workload. We show that the discovery and deployment protocol can be executed in 0.93 secs, and joining an already deployed application can be as quick as 65 ms. Also, QoS-sensitive proactive migration can be accomplished in 6 ms. <s> BIB002 </s> A Survey on Mobility-Induced Service Migration in the Fog, Edge, and Related Computing Paradigms <s> Demonstrators <s> In this paper, we propose virtualization based cyber-functions for mobile cyber-physical systems (CPSs). If a physical object of a CPS has a high level of mobility, and as the network path length from the cyber-function box gets larger, it becomes very difficult to satisfy the data exchange delay requirement. The proposed scheme can perform the migration of the cyber-functions to an appropriate location on the cyber-infrastructure using virtualization techniques. <s> BIB003 </s> A Survey on Mobility-Induced Service Migration in the Fog, Edge, and Related Computing Paradigms <s> Demonstrators <s> New generations of cloud applications are increasingly complex and pose lower latency requirements. e la er is forcing the industry to reduce network latency by adding computation nodes near the edge of the network, also known as Fog Computing. To utilize the Fog nodes efficiently, the dynamic placement and migration of application components must be supported. To this end, a Fog- aware application programming and deployment framework, called Foglets, has been proposed. is demonstration shows how the Foglets framework can be easily used to deploy applications in the Fog Computing infrastructure: A video streaming application allows a moving user to continue watching a video on the closest available screen. <s> BIB004
In this section, we list some of the demonstrators developed to obtain real-world evaluations of certain migration scenarios. The demonstration in BIB001 shows, through a small-scale fog computing deployment, the importance of proactively moving operators (see definition in Table 2 ) from one broker to the other following the user movement. An example video monitoring application is used to show that improper placements and migrations lead to a poor quality of experience. Aligned with this, the authors in BIB004 highlight an example usage scenario of the Foglets framework BIB002 presented earlier. More specifically, they show how context-aware migrations can be performed based on the user's position. This leads to a seamless service execution, as was observed for the considered video streaming application. The authors in BIB003 provide an SDN-based implementation of a cyber-function migration from one location on the cyber infrastructure to the other due to drone movement. Using Linux containers to implement the cyber functions, a migration downtime of 1.6s has been observed. Table 11 provides a summary of the aforementioned contributions.