In Named Data Networking (NDN), packets carry data names instead of source or destination addresses. This change of paradigm leads to a new network forwarding plane: data consumers send Interest packets, routers forward them and maintain the state of all pending Interests, which is then used to guide Data packets back to the consumers. Maintaining the pending Interest state, together with the two-way Interest and Data exchange, enables NDN routers' forwarding process to quickly detect network problems and retry multiple alternative paths. In this paper we describe an initial design of NDN's forwarding plane and evaluate its data delivery performance under adverse conditions. Our results show that this stateful forwarding plane can successfully circumvent prefix hijackers, avoid failed links, and utilize multiple paths to mitigate congestion. We also compare NDN's performance with that of IP-based solutions to highlight the advantages of a stateful forwarding plane.

Abstract-Current network infrastructures exhibit poor power efficiency, running network devices at full capacity all the time regardless of the traffic demand and distribution over the network. Most research on router power management are at component level or link level, treating routers as isolated devices. A complementary approach is to facilitate power management at network level by routing traffic through different paths to adjust the workload on individual routers or links. Given the high path redundancy and low link utilization in today's large networks, this approach can potentially allow more network devices or components to go into power saving mode. This paper proposes an intra-domain traffic engineering mechanism, GreenTE, which maximizes the number of links that can be put into sleep under given performance constraints such as link utilization and packet delay. Using network topologies and traffic data from several widearea networks, our evaluation shows that GreenTE can reduce line-cards' power consumption by 27% to 42% under constraints that the maximum link utilization is below 50% and the network diameter remains the same as in shortest path routing.

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We report the development of a new gelation mechanism and a new family of polymers that self-assembles to form gels in a thermoreversible fashion. The polymers are block or star copolymers with a central hydrophilic poly(ethylene glycol) (PEG) segment (A) and temperature responsive poly(Nisopropylacrylamide) (PNIPAAm) terminal segments (B). Copolymers of various architectures, AB, A(B) 2, A(B)4, and A(B)8, were synthesized to investigate the structures and properties relationship. At 5 °C, the viscosities of 20 wt % solutions were between 700 and 950 cP, and they could be easily injected through a 25 G needle. Upon warming to body temperature, A(B)2, A(B)4, and A(B)8 formed a strong associative network gel with aggregates of PNIPAAm segments acting as physical cross-links, whereas AB formed a weaker gel by micellar packing and entanglement. The values of elastic modulus, loss tangent, and yield strength were 1000-2500 Pa, 0.24-0.62, and 200-860 Pa, respectively. The gelation kinetic was fast; a typical gelation time for a solution of 5 mL in volume was less than a minute. No significant syneresis was observed after 2 months at 37 °C. DSC results indicated that the thermal behavior of material was completely reversible even after 30 heat-and-cool cycles. These materials are promising candidates for in-situ gelation applications such as injectable drug delivery, tissue engineering scaffolds, and anatomical barriers.

In Named Data Networking (NDN) architecture, packets carry data names rather than source or destination addresses. This change of paradigm leads to a new data plane: data consumers send out Interest packets, routers forward them and maintain the state of pending Interests, which is used to guide Data packets back to the consumers. NDN routers' forwarding process is able to detect network problems by observing the two-way traffic of Interest and Data packets, and explore multiple alternative paths without loops. This is in sharp contrast to today's IP forwarding process which follows a single path chosen by the routing process, with no adaptability of its own. In this paper we outline the design of NDN's adaptive forwarding, articulate its potential benefits, and identify open research issues.

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h i g h l i g h t sFaeces mixed with sand can be smouldered in a self-sustaining process. This process achieves elimination of biological hazards. A robust self-sustaining region for different parameters is identified. Is promising as the basis for a new, energy efficient waste treatment approach. a b s t r a c tThe poor management of human excreta in developing countries is among the most prominent global issues due to its negative impact on public health. This work demonstrates for the first time that self-sustaining smouldering of faeces mixed with sand is a feasible alternative to incineration for rapid destruction of waste. Self-sustaining smouldering requires minimal energy input and pre-drying of faeces compared to incineration. This process ensures the elimination of biological hazards via long residence times (>20 min) at high temperatures (>400°C). Surrogate faeces which exhibits similar energetic, thermal, and mechanical properties to real faeces are used in this study. The parameters controlling the combustion process including moisture content, airflow rate, and sand-to-faeces ratio are mapped to establish the range of conditions where self-sustaining smouldering of faeces can be achieved. Experiments were conducted within the ranges 0-75% for moisture content, 7-108 g/min for airflow rate and 2.75-11.9 g/g for sand-to-faeces (wet basis) ratio. Preliminary validation of the parameter space is done using real dog faeces. In this work, the parameter space defining the range of conditions where self-sustaining smouldering occurs is mapped. Results show successful self-sustaining smouldering of faeces for moisture contents of up to 60%, airflow ranging from 10 to 100 g/min, and wet sand-to-faeces ratio greater than 3.25. This proof-of-concept for a smouldering reactor to treat human solid waste demonstrates that smouldering of faeces could be the basis for a new, energy efficient waste treatment approach.

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