Hybrid cloud multi-access edge computing (MEC) deployments have been proposed as efficient means to support Internet of Things (IoT) applications, relying on a plethora of nodes and data. In this paper, an overview on the area of hybrid clouds considering relevant research areas is given, providing technologies and mechanisms for the formation of such MEC deployments, as well as emphasizing several key issues that should be tackled by novel approaches, especially under the 5G paradigm. Furthermore, a decentralized hybrid cloud MEC architecture, resulting in a Platform-as-a-Service (PaaS) is proposed and its main building blocks and layers are thoroughly described. Aiming to offer a broad perspective on the business potential of such a platform, the stakeholder ecosystem is also analyzed. Finally, two use cases in the context of smart cities and mobile health are presented, aimed at showing how the proposed PaaS enables the development of respective IoT applications.

Self-healing capabilities allow software systems to overcome problems occurring during testing and run time, and thus improve overall system behavior. The PANACEA framework introduced in this paper provides a design methodology as well as ready-to-use healing elements aimed at enhancing software systems with self-healing capabilities both at design time and at run time. The PANACEA approach is based on inserting self- healing elements into the system at design and coding time, to be used later for healing at testing and run time. Specifically, the Panacea framework is based on inserting annotations into the system code at design and coding time, to later on serve as an interface for runtime monitoring, managing, configuring and healing of the annotated system components. The current embodiment of PANACEA includes several generic components that provide self-healing capabilities suited for a variety of application types. The PANACEA runtime environment automatically activates and invokes these components in order to optimize and heal the application. The PANACEA framework provides an innovative programming model that enables development of advanced self-healing applications. PANACEA introduces a paradigm shift in which software is made self-healing by design. This paradigm shift, however, is graceful since developers are not required to master neither new programming skills, nor languages. As our initial experiments demonstrate, PANACEA introduces a very small performance overhead, and scales well.

Design of Service Level Agreements (SLAs) emerges as an increasingly important discipline in business-oriented IT management. In this work, we study utility maximization of contractual obligations of a business service provider for a typical SLA. We demonstrate that using service usage and performance data as well as IT performance data, routinely collected by enterprises, efficient automated derivation of optimal response time Service Level Objectives (SLOs) of an SLA is possible. This paper addresses a specific facet of the SLA design problem not sufficiently addressed in previous studies. One common approach is to calculate SLOs attainable for the given IT infrastructure by means of simple percentile analysis. However, this methodology is business agnostic and may result in sub-optimal SLOs. Another widespread approach addresses IT infrastructure (re)design, where the goal is to enable the IT to meet specified target SLOs. In contrast to these approaches, our work proposes finding optimal response lime SLOs attainable for the given IT infrastructure in a business aware manner. We define the response time SLO optimization problem, propose an algorithm that efficiently solves it using linear optimization and percentile analysis, and evaluate our solution both analytically and experimentally.

Serverless computing has become very popular today since it largely simplifies cloud programming. Developers do no longer need to worry about provisioning or operating servers, and they have to pay only for the compute resources used when their code is run. This new cloud paradigm suits well for many applications, and researchers have already begun investigating the feasibility of serverless computing for data analytics. Unfortunately, today’s serverless computing presents important limitations that make it really difficult to support all sorts of analytics workloads. This chapter first starts by analyzing three fundamental trade-offs of today’s serverless computing model and their relationship with data analytics. It studies how by relaxing disaggregation, isolation, and simple scheduling, it is possible to increase the overall computing performance, but at the expense of essential aspects of the model such as elasticity, security, or sub-second activations, respectively. The consequence of these trade-offs is that analytics applications may well end up embracing hybrid systems composed of serverless and serverful components, which we call ServerMix in this chapter. We will review the existing related work to show that most applications can be actually categorized as ServerMix.