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This paper presents mmCPTP, a cross-layer end-toend protocol for fast delivery of data over mmWave channels associated with emerging 5G services. Recent measurement studies of mmWave channels in urban micro cellular deployments show considerable fluctuation in received signal strength along with intermittent outages resulting from user mobility. This results in significant impairment of end-to-end data transfer throughput when regular TCP is used to transport data over such mmWave channels. To address this issue, we propose mmCPTP, a novel cross-layer end-to-end data transfer protocol that sets up a transport plug-in at or near the base station and uses feedback from the lower layer (RLC/MAC) to opportunistically pull data at the mobile client without the slow start and probing delays associated with TCP. The system model and end-to-end protocol architecture are described and compared with TCP and IndirectTCP (I-TCP) in terms of achievable data rate. The proposed mmCPTP protocol is evaluated using NS3 simulation for 5G NR (New Radio) considering a high-speed mobile user scenario. The system is further validated using a proof-of-concept prototype which emulates the high-speed mmWave/NR access link with traffic shaping over Gbps ethernet. Results show significant performance gains for mmCPTP over TCP and I-TCP (2.5x to 17.2x, depending on the version). 

Graph-based namespaces are being increasingly used to represent the organization of complex and ever-growing information eco-systems and individual user roles. Timely and accurate information dissemination requires an architecture with appropriate naming frameworks, adaptable to changing roles, focused on content rather than network addresses. Today's complex information organization structures make such dissemination very challenging. To address this, we propose POISE, a name-based publish/subscribe architecture for efficient topic-based and recipient-based content dissemination. POISE proposes an information layer, improving on state-of-the-art Information-Centric Networking solutions in two major ways: 1) support for complex graph-based namespaces, and 2) automatic name-based load-splitting. POISE supports in-network graph-based naming, leveraged in a dissemination protocol which exploits information layer rendezvous points (RPs) that perform name expansions. For improved robustness and scalability, POISE supports adaptive load-sharing via multiple RPs, each managing a dynamically chosen subset of the namespace graph. Excessive workload may cause one RP to turn into a ``hot spot'', impeding performance and reliability. To eliminate such traffic concentration, we propose an automated load-splitting mechanism, consisting of an enhanced, namespace graph partitioning complemented by a seamless, loss-less core migration procedure. Due to the nature of our graph partitioning and its complex objectives, off-the-shelf graph partitioning, e.g., METIS, is inadequate. We propose a hybrid, iterative bi-partitioning solution, consisting of an initial and a refinement phase. We also implemented POISE on a DPDK-based platform. Using the important application of emergency response, our experimental results show that POISE outperforms state-of-the-art solutions, demonstrating its effectiveness in timely delivery and load-sharing. 

Abstract Quantum many-body systems away from equilibrium host a rich variety of exotic phenomena that are forbidden by equilibrium thermodynamics. A prominent example is that of discrete time crystals 1–8 , in which time-translational symmetry is spontaneously broken in periodically driven systems. Pioneering experiments have observed signatures of time crystalline phases with trapped ions 9,10 , solid-state spin systems 11–15 , ultracold atoms 16,17 and superconducting qubits 18–20 . Here we report the observation of a distinct type of non-equilibrium state of matter, Floquet symmetry-protected topological phases, which are implemented through digital quantum simulation with an array of programmable superconducting qubits. We observe robust long-lived temporal correlations and subharmonic temporal response for the edge spins over up to 40 driving cycles using a circuit of depth exceeding 240 and acting on 26 qubits. We demonstrate that the subharmonic response is independent of the initial state, and experimentally map out a phase boundary between the Floquet symmetry-protected topological and thermal phases. Our results establish a versatile digital simulation approach to exploring exotic non-equilibrium phases of matter with current noisy intermediate-scale quantum processors 21 . 

With the increasing diversity of application needs (datacenters, IoT, content retrieval, industrial automation, etc.), new network architectures are continually being proposed to address specific and particular requirements. From a network management perspective, it is both important and challenging to enable evolution towards such new architectures. Given the ubiquity of the Internet, a clean-slate change of the entire infrastructure to a new architecture is impractical. It is believed that we will see new network architectures coming into existence with support for interoperability between separate architectural islands. We may have servers, and more importantly, content, residing in domains having different architectures. This paper presents COIN, a content-oriented interoperability framework for current and future Internet architectures. We seek to provide seamless connectivity and content accessibility across multiple of these network architectures, including the current Internet. COIN preserves each domain’s key architectural features and mechanisms while allowing flexibility for evolvability and extensibility. We focus on Information-Centric Networks (ICN), the prominent class of Future Internet architectures. COIN avoids expanding domain-specific protocols or namespaces. Instead, it uses an application-layer Object Resolution Service to deliver the right “foreign” names to consumers. COIN uses translation gateways that retain essential interoperability state, leverages encryption for confidentiality, and relies on domain-specific signatures to guarantee provenance and data integrity. Using NDN and MobilityFirst as important candidate solutions of ICN, and IP, we evaluate COIN. Measurements from an implementation of the gateways show that the overhead is manageable and scales well. 

The Internet is composed of many interconnected, interoperating networks. With the recent advances in Future Internet design, multiple new network architectures, especially Information-Centric Networks (ICN) have emerged. Given the ubiquity of networks based on the Internet Protocol (IP), it is likely that we will have a number of different interconnecting network domains with different architectures, including ICNs. Their interoperability is important, but at the same time difficult to prove. A formal tool can be helpful for such analysis. ICNs have a number of unique characteristics, warranting formal analysis, establishing properties that go beyond, and are different from, what have been used in the state-of-the-art because ICN operates at the level of content names rather than node addresses. We need to focus on node-to-content reachability, rather than node-to-node reachability. In this paper, we present a formal approach to model and analyze information-centric interoperability (ICI). We use Alloy Analyzer’s model finding approach to verify properties expressed as invariants for information-centric services (both pull and push-based models) including content reachability and returnability. We extend our use of Alloy to model counting, to quantitatively analyze failure and mobility properties. We present a formally-verified ICI framework that allows for seamless interoperation among a multitude of network architectures. We also report on the impact of domain types, routing policies, and binding techniques on the probability of content reachability and returnability, under failures and mobility. 

Timely, flexible and accurate information dissemination can make a life-and-death difference in managing disasters. Complex command structures and information organization make such dissemination challenging. Thus, it is vital to have an architecture with appropriate naming frameworks, adaptable to the changing roles of participants, focused on content rather than network addresses. To address this, we propose POISE, a name-based and recipient-based publish/subscribe architecture for efficient content dissemination in disaster management. POISE proposes an information layer, improving on state-of-the-art Information-Centric Networking (ICN) solutions such as Named Data Networking (NDN) in two major ways: 1) support for complex graph-based namespaces, and 2) automatic name-based load-splitting. To capture the complexity and dynamicity of disaster response command chains and information flows, POISE proposes a graph-based naming framework, leveraged in a dissemination protocol which exploits information layer rendezvous points (RPs) that perform name expansions. For improved robustness and scalability, POISE allows load-sharing via multiple RPs each managing a subset of the namespace graph. However, excessive workload on one RP may turn it into a “hot spot”, thus impeding performance and reliability. To eliminate such traffic concentration, we propose an automatic load-splitting mechanism, consisting of a namespace graph partitioning complemented by a seamless, loss-less core migration procedure. Due to the nature of our graph partitioning and its complex objectives, off-the-shelf graph partitioning, e.g., METIS, is inadequate. We propose a hybrid partitioning solution, consisting of an initial and a refinement phase. Our simulation results show that POISE outperforms state-of-the-art solutions, demonstrating its effectiveness in timely delivery and load-sharing.