Karsten Oberle

A Real-time Service Oriented Infrastructure

The advancements in distributed computing have driven the emergence of service-based infrastructures that allow for on-demand provision of ICT assets. Taking into consideration the complexity of distributed environments, significant challenges exist in providing and managing the offered on-demand resources with the required level of Quality of Service (QoS), especially for real-time interactive and streaming applications. In this paper we propose an approach for providing real-time QoS guarantees by enhancing service oriented infrastructures with coherent and consistent real-time attributes at various levels (application, network, storage, processing). The approach considers the full lifecycle of service-based systems including service engineering, Service Level Agreement (SLA) negotiation and management, service provisioning and monitoring. QoS parameters at application, platform and infrastructure levels are given specific attention as the basis for provisioning policies in the context of temporal constraints

Network virtualization: The missing piece

Current service platforms or frameworks, e.g., cloud solutions, do not take the infrastructure, necessary for the execution of the service, sufficiently into consideration. They take resources like network connectivity for granted and do not provide an integrated networking approach considering quality of service (QoS) or other real-time aspects of the message exchange between possibly thousands of components. This paper presents the concept of a fully managed network virtualization framework to provide the required connectivity between components within a virtualized service platform respecting all service requirements, e.g. as expressed by interactive real-time services, on transport layer.

Quality of service provisioning for distributed data center inter-connectivity enabled by network virtualization

Todays service platform or Cloud service models, such as Infrastructure-as-a-Service (IaaS), enable customers to deploy and execute applications on an on-demand available infrastructure. Such platforms reduce operational expenses for the service provider and lower the entry barrier for small and medium enterprises. However, current commercial solutions do not provide sufficient quality of service (QoS) guarantees for some applications. For example, they do not support various interactive real-time applications. In this paper, we introduce a way overcome these current Cloud service limitations. We show how to provide and guarantee quality of service requirements for resource networks within an IaaS framework. Our work has focused on methods for network resource management and flow control as well as QoS models. We have developed a framework that enables QoS support for real-time services executing within an IaaS environment.

The network aspect of Infrastructure-as-a-Service

Current service platform offers that provide Infrastructure as a Service (IaaS) do not adequately meet the requirements expressed by interactive real-time services. Online application response times can not yet be enforced in virtual infrastructures without service level objectives (SLOs) that meet virtual machine interconnection constraints. This paper presents a framework spanning from the service description model over the IaaS platform interface for service level agreement (SLA) negotiation to the management of virtual network resources in an IaaS environment.

End-to-End Service Quality for Cloud Applications

This paper aims to highlight the importance of End-to-End (E2E) service quality for cloud scenarios, with focus on telecom carrier-grade services. In multi-tenant distributed and virtualized cloud infrastructures, enhanced resource sharing raises issues in terms of performance stability and reliability. Moreover, the heterogeneity of business entities responsible for the cloud service delivery, threatens the possibility of offering precise E2E service levels. Setting up proper Service-Level Agreements (SLAs) among the involved players, may become overly challenging. However, problems may be mitigated by a thoughtful intervention of standardization. The paper reviews some of the most important efforts in research and industry to tackle E2E service quality and concludes with some recommendations for additional research and/or standardization effort required to be able to deploy mission critical or interactive real-time services with high demands on service quality, reliability and predictability on cloud platforms.

Enhanced Methods for SIP based Session Mobility in a Converged Network

The worlds of fixed and mobile networks are merging towards fixed mobile converge (FMC). This process brings many challenges to networking technologies to support an optimal level of security, QoS and mobility across heterogeneous fixed and mobile access networks. Efficient mobility management mechanism able to provide desired level of mobility is one of the key issues in FMC development. This paper presents enhanced methods for SIP based session mobility that brings continuous mobility, privacy protection and interdomain mobility across access and core networks possibly managed by different providers. This paper is organized as follows. First an overview of the standard SIP mobility mechanisms is given with its advantages and drawbacks. Afterwards, the SIP controlled IP soft handover concept is proposed as the method to overcome standard SIP mobility shortcomings. Finally a conclusion is given.

A Path Supervision Framework A Key for Service Monitoring in Infrastructure as a Service (IaaS) Platforms

current service platforms, e.g. Cloud solutions, do not adequately address the requirements exposed from certain kind of services like real-time services. Infrastructure as a Service Platform (IaaS) supporting these service requirements, such as quality of service of the resources provided, heavily depend on measurements in order to be able to verify that the quality of service as contracted in a service level agreement (SLA) towards the IaaS platform is kept on service layer. This paper presents the concept of a path supervision framework in the context of virtualized service infrastructures, such as IaaS platforms, spanning over use cases for service monitoring and measurement methodology. Moreover, the overall monitoring framework supporting the guaranteed execution of real-time services in such an execution environment is presented.

Brokering SLAs for End-to-End QoS in Cloud Computing

In this paper, we present a brokering logic for providing precise end-to-end QoS levels to cloud applications distributed across a number of different business actors, such as network service providers (NSP) and cloud providers (CSP). The broker composes a number of available offerings from each provider, in a way that respects the QoS application constraints while minimizing costs incurred by cloud consumers.

Software-defined networks and network functions virtualization in wireline access networks

SDN and NFV are the two major concepts in the telecommunications space driving a radical industry transition towards future programmable carrier grade networks. Both technologies have received considerable attention over the last few years especially boosted by the foundation of the ETSI NFV Industry Specification Group and driven by nearly all major network operators. The application of SDN and NFV in telco networks promises a faster time to market for new services and, at the same time, a dramatic reduction of costs in both OPEX and CAPEX. Up to now the majority of efforts in that space have focused on core networks and less on wireline access networks. This paper addresses this topic by presenting the motivation and the primary use cases for applying SDN and NFV to wireline access networks as well as by analyzing the current related standards work. We conclude with an outlook on potential future work in this area, both in research and standards.