Mael Kimmerlin

SDN optimized caching in LTE mobile networks

This paper provides an overview of the current LTE architecture and the proposed solutions to integrate Software Defined Network (SDN) technology. The integration of SDN into mobile networks become Software Defined Mobile Network (SDMN), which provides new benefits such as dynamic and efficient caching. Firstly, the paper proposes the integration of SDN in LTE networks on disruptive approach that replaces current mobile transport with SDN based network. Secondly, the benefits of SDN integration to provide optimized content caching is presented. This paper presents a concrete advantage of SDMN for content delivery. Thus, the paper describes the benefits from operator and end user points of view based on a simple scenario of content delivery using dynamic caching reallocation.

Cost efficiency of mobile in-network caching

Summary Mobile data volume is growing with an annual compound rate of 61% between 2014 and 2019. To cope with the data volume growth, a more dynamic and flexible network is needed. Caching has been deployed by both mobile network operators and content providers to reduce the load on centralized data centers and gateways. In addition, software-defined networking (SDN) is a prominent solution to more flexibly and efficiently utilize the available network resources, especially in the mobile backhaul. However, installation of cache servers into the network means additional capital expenditure (CAPEX) and their daily operations incur operational expenses (OPEX). Thus, the change in cost of deploying and operating in-network caching compared with data center caching is modeled in this paper using a Finnish Long-Term Evolution reference network. In addition, this paper simulates both the SDN-optimized in-network caching system and data center caching, the results of which are utilized in the cost model. The simulation results show that, on average, in-network caching compared with caching only in data centers reduces traffic load by 45% in the network and 6% in the gateways. The cost modeling indicates that in-network caching reduces network-related CAPEX by 1.53% and OPEX by 0.49% compared with caching only in data centers. Copyright

A practical evaluation of a network expansion mechanism in an openstack cloud federation

The SSICLOPS consortium recently designed a transparent virtual network expansion mechanism for OpenStack. In this paper, we build up on this mechanism to propose features to improve the interconnection for inter-cloud federations. Based on distributed in-memory databases and High Energy Physics (HEP) workloads as two representative cloud computing workloads, we performed extensive performance evaluations to demonstrate that in a setup comprised of five sites across Europe, the performances of our interconnection agent are similar to the performances of the legacy VPNaaS feature provided by OpenStack. However, the interconnection agent is not restricted to the exemplary uses cases, as it is applicable to arbitrary workloads. This enables us to work in the direction of transparent inter-cloud live migration from a networking point of view.

Network expansion in OpenStack cloud federations

Cloud federation is receiving increasing attention due to the benefits of resilience and locality it brings to cloud providers and users. Our analysis of three diverse use cases shows that existing solutions are not addressing the federation needs of such use case applications. In this paper, we present an alternative approach to network federation, providing a model based on cloud-to-cloud agreements. In our scenarios, companies hosting their own OpenStack clouds need to run machines transparently in another cloud, provided by a company they have an agreement with. Our solution provides multiple benefits to cloud providers and users detailed in this paper. Our implementation outperforms the VPNaaS solution in OpenStack in terms of throughput.

Giving Customers Control Over Their Data: Integrating a Policy Language into the Cloud

Cloud computing offers the potential to store, manage, and process data in highly available, scalable, and elastic environments. Yet, these environments still provide very limited and inflexible means for customers to control their data. For example, customers can neither specify security of inter-cloud communication bearing the risk of information leakage, nor comply with laws requiring data to be kept in the originating jurisdiction, nor control sharing of data with third parties on a fine-granular basis. This lack of control can hinder cloud adoption for data that falls under regulations. In this paper, we show in six use cases how cloud environments can be enriched with policy language support to give customers control over cloud data. Our use cases are based on realizing policy language support in all three cloud environment layers, i.e., IaaS, PaaS, and SaaS. Specifically, we present policy-aware resource management (with OpenStack) and dynamic network configuration. With CERNs big data storage and the in-memory database Hyrise, we show realization for storage and further exemplify policy-aware cloud processing by network function virtualization which enables Orange to offload customer home gateways to the cloud. Finally, we discuss benefits of policy support in F-Secures Security Cloud. These use cases show the feasibility of realizing customer control with policy support in the cloud. Thus, our work enables customers with regulated data to tap cloud benefits and significantly broadens the market for cloud providers.

Multipath cloud federation

Deploying applications in federated clouds is becoming increasingly important. The ability to place application components in various locations is appealing to a large set of distributed applications. Components spread across a number of clouds still need to communicate with each other. Existing solutions for interconnecting clouds are using only single paths between sites, even though clouds typically have multiple up-links. This paper introduces our work on a MultiPath TCP (MPTCP) proxy suited for cloud interconnection. The proxy transforms TCP streams into multipath connections using MPTCP. By virtue of MPTCP, the bandwidth of multiple links is made available to the proxied connections and resilience can be improved without the need for additional fail-over mechanisms. The proposed solution works transparently for applications, making changes to existing applications unnecessary. Measurements of the implemented scheme confirm the additional throughput achievable and the gain in resilience.