Marc Koerner

Multiple service load-balancing with OpenFlow

Load balancers have a decisive role in every enterprise network as they serve often as an entry point and have major impact on the performance and the availability of the network. While current load balancers are mostly implemented as specific hardware components, we developed a load balancer service based on the OpenFlow controllers to handle the load of multiple services without the necessity for a specific piece of hardware. This approach integrates the network and the load balancing functionality and reduces the maintenance effort. We increase the efficiency by providing dedicated and thus specifically adapted load balancing algorithms for the involved services. For example one controller handles the standard network traffic between the server nodes and other network components, while another controller handles the load-balancing of the web-servers and another one the load-balancing of e-mail servers. Furthermore experimental measurements in the local OpenFlow island using the FlowVisor and NOX controllers prove the performance capabilities of the developed prototype.

SLA-driven Federated Cloud Networking: Quality of Service for Cloud-based Software Defined Networks

Abstract Since the cloud paradigm becomes more and more popular for the dynamic resources allocation, new techniques and performance improvements for scalability as well as new cloud services on all three layers of the cloud stack were developed. Furthermore, another well covered topic is cloud federation concerning processing power and strength. However, the flexibility of the cloud is limited in terms of network services and federated networking between autonomous cloud data-center. With the promising opportunities of Software Defined Networking (SDN), this gap can be closed and enables cloud environments to establish networking federations between autonomous data-centers and virtual network partitioning in a single cloud infrastructure. In this paper we are introducing and describing an architectural approach for a generic layered model and API based software architecture to orchestrate and federate heterogeneous networks. In particular, we present an architecture that enables Quality of Service (QoS) aware configurations of network resources in a cloud infrastructure of one data-center and federated networking between different SDN based cloud networks over and above the data-center network edge. Furthermore, this architecture uses a Service Level Agreement (SLA) protocol and language to expose Key Performance Indicators (KPI) and to negotiate appropriated QoS constrains which are applied to the virtually sliced underlying network substrate. In this way, capabilities of the orchestration and the current utilization of the network are building the foundation for dynamic negotiated SLAs and the within guaranteed QoS of network resources. The approach presented in this paper will change todays IT landscape and allows every organization to purchase required network characteristics on demand.

Evaluating SDN based Rack-to-Rack Multi-path Switching for Data-center Networks

Abstract Software defined networking becomes more and more popular in the networking community, but is still missing its triumphal procession into existing networks. Especially data-centers could benefit from this evolutionary network paradigm and get rid of many legacy parts with are still blocking the evolution how their networks are working in general. In this paper we will present an approach, use-case and performance evaluation as well, for the integration of software defined networking applications in data-centers. This approach addresses a sub topic or more precisely a single software defined networking application for enhancing inter rack communication by involving the top-of-rack and aggregation switches in a common fat-tree network topology. The basic aim is to provide some sort of load distribution mechanism on the afore mentioned network layers by using a flow based load sharing procedure with layer two multi-path. The evaluation will show that this is increasing the throughput in a rack-to-rack data exchange scenario.

Optimizing openflow load-balancing with L2 direct server return

Load-balancers have an essential role in enterprise data-centers, as their existence and performance is decisive for service provision and availability. The state of the art is that todays load-balancers are a piece of specialized embedded hardware with a proprietary operating system and application modules. In this paper we propose a concept to break up this black box model and to show how to develop a high performance LB with OpenFlow technology. In this approach we use OpenFlow network components to process the load-balancing and in order to reduce the maintenance effort and to lower the hardware cost factor. Furthermore, in case of fail-over it is redundant by concept and easier to replace by another device. The experimental evaluation of this concept proves that the concept is developed beyond a theoretical concept and the implemented solution is ready for deployment.

Service-level agreement aggregation for quality of service-aware federated cloud networking

Since the cloud paradigm becomes increasingly popular for dynamic resources allocation, the flexibility of a cloud is still limited regarding network services and their autonomous federation between different providers. The following architectural approach introduces a generic layered model to orchestrate and federate heterogeneous networks. In particular, an architecture is presented that enables quality of service (QoS) aware parameterisation of network resources in a cloud infrastructure of a single data-centre as well as for a federation. Furthermore, this architecture uses a service-level agreement (SLA) protocol and language to expose key performance indicators and to negotiate appropriate QoS constrains that are applied to the virtually sliced underlying network substrate. In this way, capabilities of the orchestration and the current utilisation of the network are building the foundation for dynamic negotiated SLAs and the within-guaranteed QoS network resources. Therefore an aggregation mechanism is illustrated for merging service-level objectives and for guaranteeing a single SLA that specifies obligations and responsibilities of all participants.

HLA — A hierarchical layer application for OpenFlow management abstraction

This paper introduces a new approach for a hierarchical OpenFlow management layer. This concept proposes a controller application which hides the complexity of the underlying network for the next higher management instance in order to reduce the management overhead and present a domain specific encapsulated control level. It is focused on real world network infrastructures and takes the design of today multiple-layer-network-providers into account. Moreover, this approach covers the management in typical multi-tenant network provider environment and unifies the control concept by using an open software defined networking control standard as communication protocol.

Oftables: A distributed packet filter

This paper introduces an innovative packet filter application called “oftables”. The application provides a new network security enforcement opportunity using OpenFlow, with a lot of advantages which will be further explained. Even more, it covers all firewall requirements and evolve the whole concept concerning performance, management, granularity and reliability. Altogether it presents an major improvement regarding packet based network traffic filtering in future data-center, enterprise or campus networks.

The OFELIA TUB-island an Europe-wide connected OpenFlow testbed

This paper introduces the OpenFlow testbed at the Technical University of Berlin, which was created in scope of the European project OFELIA. It briefly explains the need for future internet testbeds and gives a detailed overview about the entire hard- and software architecture. The concept for providing testbed resources to internal and external researchers as well as how to execute experiments will be explained. Actually, some experimental examples and results will show what can be achieved from the experimenters perspective. This testbed uses common OpenFlow networking equipment and delivers measurement samples with real world results for software defined networking environments because under laboratory conditions tested flow processing algorithms can be evaluated on a real network infrastructure.

Evaluation of a cloud federation approach based on Software Defined Networking

This paper introduces a Software Defined Networking based cloud federation approach, which enables a horizontal network federation between different cloud providers, based on a federated Software Defined Networking (SDN) layer. Thus, a new cloud federation agent is introduced, designed, and exemplary evaluated. The described agent is managing the set up and sustainment of a Software Defined Network on the underlying, federated cloud networks. Therefore it includes a virtualization component to virtualize the underlying physical SDN substrate. This offers tenants the opportunity to use the clouds Infrastructure as a Service (IaaS) model with fine grained access to the virtualized SDN resources. Theses resources are exposed via an OpenFlow interface and deployed on top of the SDN virtualized control plane. This provides an innovative management and control capability of a virtual SDN (vSDN) substrate which gives tenants the freedom to deploy virtual network appliances or services, also known as Network Function Virtualization (NFV), on top of the allocated vSDN.

MAC Based Dynamic VLAN Tagging with OpenFlow for WLAN Access Networks

Abstract Many network device vendors are providing a vendor specific VLAN based access solutions for WLAN clients. This applications allows network operators to specify WLAN devices which automatically fall into their department specific networks ans allows them to access their local resources like e.g. printers. The configuration of these VLAN mappings is usually manufacturer specific and depends also on the local VLAN policies. However, the presented OpenFlow approach on the other hand presents a solution to encapsulate this functionality as network application. Thus, an architecture, implementation, and evaluation is presented in order to demonstrate that this particular functionality can be easily realized in an OpenFlow network application.