Use cases for network determinism may involve the traversal of multiple network domains. A typical example is the edge-cloud virtualization of the controllers for industrial automation, where the end-to-end data path may include a private mobile network and a wired local-area network within the factory premises, a public transport network between the factory and the edge-cloud data center, and a switching fabric within the same data center. Maintaining deterministic guarantees throughout these domains, likely operated by different providers, is a daunting task when each domain relies on its own control and data-plane technologies for satisfaction of its allocated portion of the end-to-end requirements. We propose a universal model for determinism in wired packet networks that simplifies the realization of deterministic services over chains of network domains. The model builds on a novel traffic shaper where routing information constrains the packet scheduling decisions. The shaper, and therefore the provisioning of resources for every deterministic service, is only needed at the ingress edge of each wired domain. We conjecture perdomain latency bounds enforced by the shaper and corroborate them with experimental evidence. The bounds are easy to combine for multi-domain network paths.

The next-generation 5G mobile network architecture will support the rapid deployment of new, dynamic network services that are capable of responding to current network conditions and demands. Software-defined Networking (SDN), virtualization technologies, and real-time analytics are the core components that will enable an adaptive and responsive 5G network. We present a case study of a real-time communications (RTC) video service that highlights the manner in which the core components (SDN, virtualization, analytics) allow a flexible and elastic 5G network. Because an end-to-end 5G network does not exist today, we construct one using artifacts from the current 4G/LTE network to host our dynamic network enabled RTC service. We identify three main insights from executing our service that could prove beneficial to the 5G network evolution: need for efficient horizontal control, need to limit identifier proliferation, and the existence of control-plane network functions in service network-function graphs.

In HTTP adaptive streaming (HAS) applications multiple video clients sharing the same wireless channel may experience different video qualities as result of both different video content complexity and different channel conditions. This causes unfairness in the end-user video quality. In this paper, we propose a quality-fair adaptive streaming (QFAS) solution to deliver fair video quality to HAS clients competing for the same resources in an LTE cell. In the QFAS framework the share of radio resource is optimized according to video content characteristics and channel condition. The proposed solution is compared with other state-of-the-art strategies and numerical results in terms of SSIM quality metric shows that it significantly improves the quality fairness among heterogeneous HAS users.

TCP performance in contention-based multi-hop wireless networks is shaped by two main factors, which are unlike the wired network case. First, the maximum throughput for a given topology and flow pattern is reached for a specific congestion window. This window is very difficult to detect under dynamically changing network traffic. Second, the excessive control traffic consumes channel bandwidth more severely than in the wired case. Our analysis and simulations show that the smaller TCP ACK packets consume channel resource comparable to the much longer TCP DATA packets, over high-speed connections. Motivated by this observation, we propose a new approach to improve TCP performance by further lowering the number of control packets compared with the known methods. Extensive simulations show that our strategy improves the TCP throughput up to 205% compared with the regular TCP. Although our simulation is based on 802.11, the same idea works in other networks using a contention-based MAC design.

In multi-hop wireless networks, unlike the wired ones, two main factors affect the TCP performance. First, the maximum throughput is reached for a specific congestion window that is very difficult to detect under dynamically changing network traffic. Second, the excessive control traffic consumes channel bandwidth more severely than in the wired case. Our analysis and simulations show that, over high-speed connections, the much shorter ACKtcppackets consume the channel capacity comparable to the much longer data packets. Motivated by this insight, we first propose using different routes for data and ACK flows in a grid sensor network which achieves 60~100% performance gain. After that, we reformulate and improve an existing idea for TCP performance improvement by further lowering the number of control packets compared to the known methods. Extensive simulations show that this improves the TCP throughput up to 200% compared to the regular TCP, in long-hop wireless networks.