Data synchronization-long a staple in le systems-is emerging as a signicant communications primitive. In a distributed system, data synchronization resolves di erences among distributed sets of information. In named data networking (NDN), an information-centric communications architecture, data synchronization between multiple nodes is widely used to support basic services, such as public key distribution, le sharing, and route distribution. While existing NDN synchronization schemes are unctional, their implementations rely on log-based representations of information, which creates a limitation on their performance and scalability. This paper presents iSync, a high performance synchronization protocol for NDN. iSync supports efficient data reconciliation by representing the synchronized datasets using a two-level invertible Bloomfilter (IBF) structure. A set-differences can be found by subtracting a remote IBF from a local IBF. The protocol can obtain multiple differences from a single round of data exchange, and does not require prior context in most application scenarios. We evaluated iSync's performance by comparing it to the CCNx synchronization protocol. Experiments show that iSync is about eight times faster across a range of network topologies and sizes, and that it reduces the number of packets sent by about 90%.

Energy efficient routers are a promising step forward in the road-map towards energy efficient networking. In this paper, we use gigabit routers to measure and evaluate the impacts of green technologies in different scenarios. These programmable NetFPGA based routers come with the inbuilt feature of frequency scaling which can reduce the operational frequency of the board by half from 125MHz to 62.5MHz. Router power consumption is compared for standard and low frequency modes with different numbers of activated ports. Perpacket and per-byte energy costs in different cases with different packet sizes are measured and analyzed to evaluate the effects of frequency adjustment. Finally, a simple energy model for real traffic is proposed and evaluated. This paper reveals the internal power usage of a gigabit router at the granularity of packet, and header and payload byte level, and offers the reader a clear understanding of the potential power savings at different operational router frequencies, for different numbers of activated ports, various traffic loads and packet sizes, which would assist the green data center networks.

Recently, energy expenditures of the Internet have increased dramatically, raising energy issue of routers an urgent problem in relative research areas. In fact, much device surplus and redundancy are introduced during network planning for rarely appeared traffic peak hours and device failures, wasting energy most of the time. In this work, an energy-aware architecture is proposed for routers, which could trade system performance for energy savings while traffic is low by scaling frequencies of its inner components. We also explore multi-frequency modulation strategies to optimize the energy saving effect. The result shows that our prototype router could save about 40\% of its peak power consumption.

With the rapid expansion of customer population and link bandwidth, energy expenditures of the Internet have been rising dramatically. To gain energy efficiency, we propose a novel router architecture, which allows each of its modules to adjust frequency according to traffic loads. Several modulation strategies are also discussed to ensure dwell time on low energy states and reduce blind switches. Our preliminary results show that the frequency adjustment router could save up to 40% of the total energy consumption.