Extending TOSCA for Edge and Fog Deployment Support

Abstract

The emergence of fog and edge computing has complemented cloud computing in the design of pervasive, computing-intensive applications. The proximity of fog resources to data sources has contributed to minimizing network operating expenditure and has permitted latency-aware processing. Furthermore, novel approaches such as serverless computing change the structure of applications and challenge the monopoly of traditional Virtual Machine (VM)-based applications. However, the efforts directed to the modeling of cloud applications have not yet evolved to exploit these breakthroughs and handle the whole application lifecycle efficiently. In this work, we present a set of Topology and Orchestration Specification for Cloud Applications (TOSCA) extensions to model applications relying on any combination of the aforementioned technologies. Our approach features a design-time “type-level” flavor and a run time “instance-level” flavor. The introduction of semantic enhancements and the use of two TOSCA flavors enables the optimization of a candidate topology before its deployment. The optimization modeling is achieved using a set of constraints, requirements, and criteria independent from the underlying hosting infrastructure (i.e., clouds, multi-clouds, edge devices). Furthermore, we discuss the advantages of such an approach in comparison to other notable cloud application deployment approaches and provide directions for future research.

A feature-based survey of Fog modeling languages

“…Extended TOSCA. This solution proposes to provide support for optimizing TOSCA deployment templates in a Fog/Multi Cloud environment [26].…”

Standards‐based modeling and deployment of serverless function orchestrations using BPMN and TOSCA

“…Dehury et al 70 introduce a TOSCA‐based approach for modeling data pipelines which can also incorporate serverless components such as FaaS functions. Tsagkaropoulos et al 71 introduce TOSCA extensions for edge and fog deployment modeling which also include constructs for modeling FaaS‐hosted functions on provider‐managed platforms and on premises platforms, however, without covering the topic of modeling function orchestrations as well as their deployments. Moreover, existing graph‐based models can be used for analyzing the application structure and identification of hot spots 72 or comparing deployment models in a uniform way 73 .…”

TOSCAdata: Modelling data pipeline applications in TOSCA

“…Broadening the applicability of the TOSCA from just cloud service management, Tsagkaropoulos et al [36] extended the TOSCA standard for providing support to edge and fog deployment of the services. The authors have developed a set of TOSCA node types, policies, relationships, capabilities, etc suitable for deployment of software components in fog environment taking the resource constraints into consideration.…”