Global state, local decisions: Decentralized NFV for ISPs via enhanced SDN

The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.Peer ReviewedPostprint (author's final draft

A Novel Approach To Classify Cloud Entities: Universal Cloud Classification (UCC)

One of the fundamental requirements of Cloud Computing is the capability to provide scalable, transparent and isolated networks. This is achieved by using L2 segmentation via 802.1Q VLANs or overlay approaches such as 802.1ad, VxLAN, ”Stateless Transport Tunneling” (STT) or ”Network Virtualization using Generic Routing Encapsulation” (NVGRE). All of these technologies struggle to provide the required level of scalability, flexibility, performance and network isolation within a Data Center. Research efforts in the area of classification have fundamentally approached these challenges by introducing identifiers for segmentation or providing overlay solutions to tunnel traffic. However, these research approaches are too specific without tackling the actual Cloud Computing classification challenges. Here, we investigate classification approaches with the goal of introducing a scalable, optional, hierarchical, end-to-end and transparent Layer 3 provider, service and tenant isolation scheme. This proposal addresses major challenges and limitations of current cloud classification schemes by offering these five advantages: (1) hierarchical endto-end classification, (2) transparency to upper-layer protocols, (3) optional for en-route and endpoint evaluation, (4) flexibility, and (5) improved performance over current overlay technologies. The solution proposal will be implemented and evaluated based on its feasibility, functionality, performance and usability in cloud-related use-cases

Building Programmable Wireless Networks: An Architectural Survey

In recent times, there have been a lot of efforts for improving the ossified Internet architecture in a bid to sustain unstinted growth and innovation. A major reason for the perceived architectural ossification is the lack of ability to program the network as a system. This situation has resulted partly from historical decisions in the original Internet design which emphasized decentralized network operations through co-located data and control planes on each network device. The situation for wireless networks is no different resulting in a lot of complexity and a plethora of largely incompatible wireless technologies. The emergence of "programmable wireless networks", that allow greater flexibility, ease of management and configurability, is a step in the right direction to overcome the aforementioned shortcomings of the wireless networks. In this paper, we provide a broad overview of the architectures proposed in literature for building programmable wireless networks focusing primarily on three popular techniques, i.e., software defined networks, cognitive radio networks, and virtualized networks. This survey is a self-contained tutorial on these techniques and its applications. We also discuss the opportunities and challenges in building next-generation programmable wireless networks and identify open research issues and future research directions.Comment: 19 page

ClouNS - A Cloud-native Application Reference Model for Enterprise Architects

The capability to operate cloud-native applications can generate enormous business growth and value. But enterprise architects should be aware that cloud-native applications are vulnerable to vendor lock-in. We investigated cloud-native application design principles, public cloud service providers, and industrial cloud standards. All results indicate that most cloud service categories seem to foster vendor lock-in situations which might be especially problematic for enterprise architectures. This might sound disillusioning at first. However, we present a reference model for cloud-native applications that relies only on a small subset of well standardized IaaS services. The reference model can be used for codifying cloud technologies. It can guide technology identification, classification, adoption, research and development processes for cloud-native application and for vendor lock-in aware enterprise architecture engineering methodologies