A Service-Centric Orchestration Protocol for Self ... - IEEE Xplore

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A Service-Centric Orchestration Protocol for Self-Organizing Autonomic Management Systems Javier Rubio-Loyola, CINVESTAV Tamaulipas Carlos Mérida-Campos and Joan Serrat, Universitat Politècnica de Catalunya Daniel Fernandes Macedo, Federal University of Minas Gerais Steven Davy, Waterford Institute of Technology Zeinab Movahedi and Guy Pujolle, Laboratoire d’Informatique Paris 6

Abstract This article presents a service-centric orchestration protocol for self-interested autonomic management systems that supports the coalition formation process in largescale collaborative and competitive environments. It supports environments in which coalition formations are carried out targeting multiple service requests at the same time, and in which the autonomic management systems compete to work in the most appropriate coalition. The protocol exploits the benefits of social networking in favor of manageability and scalability. Its performance is analyzed taking into account crucial aspects of self-organizing systems such as stability and convergence to optimal coalition formation results.

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n the Future Internet most services will be delivered with end-to-end quality of service (QoS), security and reliability constraints, and it will be of crucial importance to have secure, reliable, scalable and efficient mechanisms to facilitate the cooperation of networks to support these types of services. Self-management of networks deals with the ever increasing complexity of the associated processes. The grounds of self-management systems are contained in the IBM manifesto [1], which describes a self-managed system including the necessary components for collecting data relevant to the system environment, and for reacting to keep the system in a desirable state. However, this paradigm does not consider the particularities of emerging network management. Indeed, in networking, a number of management systems have to coexist performing different management tasks covering various nodes, links, and services. In addition, the existence of several management standards and protocols makes the problem of network management much more complex than a single isolated system. As it is not practical to devise a single autonomic control loop that deals with all the functional aspects involved in network management, it will be necessary to envisage a scenario where multiple specialized control loops will coexist and be responsible for the global network behavior. This was one of the challenges faced by the EU IST AUTOI (Autonomic Internet) Project [2], where a new concept, the Orchestration Plane (OP), was introduced to act as a mediator among several Autonomic Management Systems (AMSs). The OP is an effective solution to deal with management domain heterogeneity and integration of several AMSs that

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would not be able to interoperate without a set of translation, negotiation, federation, and deployment functions. A key mediation role of the OP takes place at epoch of the coalition formation, where complex services will be composed from other available services offered by the AMSs. As the AMSs involved in a coalition can belong to different administrative domains (most probably competitors), they will try to implement coalition strategies aligned to their own self-interests. This motivates the need for a well-defined, functional, scalable Orchestration Protocol supporting such coalition formations among AMSs. This article describes an Orchestration Protocol for selfinterested collaborative AMSs that provide support for the coalition formation process in federated networks. The novelty resides in the proposition of a service-centric protocol that supports coalition formation processes to address multiple simultaneous objectives, where AMSs compete to work in the most appropriate service coalition, according to their selfinterests. In this article we first describe the framework of this work. We then describe the protocol, followed by experimental results. Finally, we provide the related work and conclusions, respectively.

AutoI Orchestration Framework Autonomic Internet (AutoI) The Autonomic Internet (AutoI) solution [2] suggests a transition from a service agnostic Internet to a service-aware network, managing network resources by applying autonomic principles. AutoI has developed a self-managing virtual net-

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To service requesters

Orchestration plane (OP) Distributed orchestration component Dynamic planner Other DOCs

Core behaviors

Service enablers plane (SP)

Federation Governance

AMS Services Resources

Distribution Negotiation

Service enablers plane (SP)

Knowledge plane (KP)

Knowledgerelated behaviors

AMS Services Resources

Other AMSs

Management plane (MP) Virtualization plane (VP)

Orchestration protocol

Figure 1. Orchestration framework and protocol scope.

work resource overlay [3] that can span heterogeneous networks, supporting service mobility, security, quality of service and reliability. AutoI employs five functional planes: Virtualization, Management, Service Enablers, Knowledge, and Orchestration. The Virtualization Plane (VP) provides the means to virtualize physical resources with the aim of allowing on-the-fly (re)configuration and migration of network resources. The Management Plane (MP) deals with the maintenance and creation of individual control loops [1], realized by Autonomic Management Systems (AMSs) that perform the MAPE (Monitor, Analyse, Plan and Execute) functions [1] over the virtual resources. The Service Enablers Plane (SP) is responsible for discovery and deployment of application (VPNs, file sharing services, multimedia, etc.) and networking (routing, forwarding, etc.) services. The Knowledge Plane (KP) implements a distributed information service, providing all the other planes with their required information. While the SP and the MP deal with the management of a single service and control loop, the Orchestration Plane (OP) [4] mediates and guides the interaction among several AMSs. Since the AMSs are autonomic entities, the OP acts as a mediator, detecting and managing conflicts, determining SLAs that satisfy all involved parties. The interested reader may consult [3] and [5] for a description of the AutoI architecture and key implementation aspects, respectively.

AutoI Orchestration Framework The Orchestration Plane [4] acts as a control workflow mechanism for the lifecycle of AMSs, into which any number of components can be plugged in and out in order to achieve the required functionality. As depicted in Fig. 1, the OP is made up of one or more Distributed Orchestration Components (DOCs). Each DOC can control the flow of several AMSs.

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DOCs facilitate the cooperation among AMSs and cooperate with other DOCs in order to ensure end-to-end QoS. Each DOC consists of several functional elements, which are graphically depicted in Fig. 1. The Dynamic Planner is an intelligent workflow engine for the execution of management tasks and actions required by the DOC, called Behaviors. Two types of Behaviors are implemented. Knowledge-related Behaviors supervise the collection, dissemination and storage of the required knowledge. Core Behaviors deal with the integration of AMSs and if required, the grouping of two or more DOCs. The grouping of DOCs and AMSs, tailored ad-hoc to achieve a required functionality, is defined as an orchestration domain. The DOC implements four Core Behaviors: the Federation Behavior enables the DOC to supervise the entire federation process for orchestrated domains while they maintain different SLAs; the Negotiation Behavior enables the DOC and AMSs to negotiate in order to fulfill their business objectives; the Distribution Behavior enables the DOCs with communication and control capabilities to split complex service requests into parts that would run on multiple AMSs; finally, the Governance Behavior enables the DOCs to police the actions of the AMSs to ensure that the high-level orchestration goals are maintained and also to prevent potential instabilities due to AMSs’ changes.

Service Centric Orchestration Marketplace Central to our study is the OP functionality to coordinate and to provide the means for a service-centric marketplace in which the AMSs offer their services, so that more complex services are composed and maintained based on the requirements of the former. The framework of this service-centric marketplace, depicted in Fig. 1, illustrates also the spanning scope of the orchestration protocol presented in this work.

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Set up phase Start

•Update the population of AMSs •Update social network between AMS: SNl=(V,E) •Update the matrix of service tasks T=[Tkp] •Define stand alone initial coalitional setups for all AMSs •Maximum number of negotiation rounds: n

Multi-market transition phase

All (p) service tasks sets have been resolved?

Yes

End

No Next multi-service provisioning cycle ∈ [Tkp]

All AMSs have taken coalitional actions

Yes

Negotiation round for this service task