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91.
在移动网络环境下,因各移动蜜罐资源有限、攻击注入手段灵活多变,需要动态部署蜜网以协同地检测攻击行为特征。然而现有蜜网易遭受特征识别攻击、网内恶意流量肆意传播、不能跨蜜罐迁移连接。为此,基于软件定义网络(software defined networking,SDN)技术,设计了一种智能协同蜜网(intelligent and collaborative Honeynet,ic-Honeynet)系统。它由逆向连接代理模块和蜜网控制器组成,它的优势在于逐一克服了上述3个缺陷。最后,搭建了一个ic-Honeynet实验环境,并验证了该系统的有效性。实验结果表明:该系统吞吐量近乎线速,高达8.23 Gbit/s;响应时延额外增加很小,仅在0.5~1.2 ms区间变化;连接处理能力也很强,可高达1 473个连接/s。 相似文献
92.
The emerging software‐defined networking (SDN) paradigm introduces new opportunities to improve network performance due to the flexibility and programmability provided by a logically centralized element named controller. However, a rapid adoption of the full SDN architecture is difficult in the short term due to economic and technical reasons. This paper faces the SDN nodes replacement problem during the transition from traditional IP networks to fully deployed SDN networks. Six different replacement methods are proposed to select the most appropriate set of traditional IP nodes to be upgraded to SDN‐enabled switches at a particular transition stage. To show the effectiveness of the proposed methods, they have been applied on an optimization problem currently studied by the research community: the power consumption problem. An integer linear programming formulation is presented to solve it and a genetic algorithm is evaluated through simulations on realistic network topologies. Results highlight that energy‐efficiency in hybrid IP/SDN networks can be significantly improved by only replacing a reduced number of IP nodes. 相似文献
93.
Recently, content‐centric networking (CCN) has become one of the important technologies for enabling the future networks. Along with its recognized potentialities as a content retrieval and dissemination solution, CCN has been also recently considered as a promising architecture for the Internet of things (IoT), because of 2 main features such as named‐based routing and in‐network caching. However, IoT is characterized by challenging features: small storage capacity of resource‐constrained devices due to cost and limitation of energy and especially transient data that impose stringent requirements on the information freshness. As a consequence, the intrinsic caching mechanisms existing in CCN approach do not well suit IoT domains; hence, providing a specific caching policy at intermediate nodes is a very challenging task. This paper proposes an effective multiattribute in‐network caching decision algorithm that performs a caching strategy in CCN‐IoT network by considering a set of crucial attributes including the content store size, hop count, particularly key temporal properties like data freshness, and the node energy level. Simulation results proved that our proposed approach outperforms 2 cache management schemes (probabilistic least recently used and AlwaysCache–first in first out in terms of improving total hit rate, reducing data retrieval delay, and enhancing content reusability in IoT environment). 相似文献
94.
Minh‐Tuan Thai Ying‐Dar Lin Yuan‐Cheng Lai 《International Journal of Communication Systems》2018,31(10)
Prior service chaining systems address server and network load balancing issues individually, which may not ensure efficient system performance. To this end, in this paper, we study the design, implementation, complexity analysis, and evaluation of Nearest First and Local‐Global Transformation algorithm, which jointly supports server and network load balancing for chaining virtualized network functions (VNFs) in data center environment. The algorithm firstly constructs service chains by a greedy strategy, which both considers server and network latency. Then a searching technique, which replaces a selected VNF with another candidate and swaps the order of VNFs in service chains, is applied to improve the solutions. We have implemented the algorithm using Software‐defined networking and OpenFlow concepts. The numerical results indicate that, compared with a sequential approach, Nearest First and Local‐Global Transformation increases the system bandwidth utilization up to 45%. The results also show that it is worth applying the second phase of our algorithm since it considerably enhances the system performance by 20%. 相似文献
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网络功能虚拟化(NFV)和软件定义网络(SDN)已被业界普遍认定为下一代电信网络发展的主要方向,编排器作为未来网络的“大脑”,成为运营商灵活管理网络、最大化发挥新技术优势的关键.首先阐述了编排器在下一代网络中的核心地位,并对编排器的技术架构进行介绍.而后从标准化和开源的角度对编排器产业发展情况进行介绍和分析.最后阐述了编排器产业发展中标准与开源的关系,编排器与网管运营支撑系统(OSS)的融合、编排器对SDN的支持以及依托编排器实现网络自动化智能化运营的理念. 相似文献
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98.
Andrea Cardaci Luca Caviglione Erina Ferro Alberto Gotta 《International Journal of Satellite Communications and Networking》2017,35(4):307-321
During the last decade, the Web has grown in terms of complexity, while the evolution of the HTTP (Hypertext Transfer Protocol) has not experienced the same trend. Even if HTTP 1.1 adds improvements like persistent connections and request pipelining, they are not decisive, especially in modern mixed wireless/wired networks, often including satellites. The latter play a key role for accessing the Internet everywhere, and they are one of the preferred methods to provide connectivity in rural areas or for disaster relief operations. However, they suffer of high‐latency and packet losses, which degrade the browsing experience. Consequently, the investigation of protocols mitigating the limitations of HTTP, also in challenging scenarios, is crucial both for the industry and the academia. In this perspective, SPDY, which is a protocol optimized for the access to Web 2.0 contents over fixed and mobile devices, could be suitable also for satellite links. Therefore, this paper evaluates its performance when used both in real and emulated satellite scenarios. Results indicate the effectiveness of SPDY if compared with HTTP, but at the price of a more fragile behavior when in the presence of errors. Besides, SPDY can also reduce the transport overhead experienced by middleboxes typically deployed by service providers using satellite links. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
99.
A tree‐based algorithm for virtual infrastructure allocation with joint virtual machine and network requirements
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Ramon de Oliveira Guilherme Piegas Koslovski 《International Journal of Network Management》2017,27(1)
Cloud providers have introduced the on‐demand provisioning of virtual infrastructures (VIs) to deliver virtual networks of computing resources as a service. By combining network and computing virtualization, providers allow traffic isolation between hosted VIs. Taking advantage of this opportunity, tenants have deployed private VIs with application‐optimized network topologies to increase quality of experience of final users. One of the main open challenges in this scenario is the allocation of physical resources to host VIs in accordance with quality of service computing (eg, virtual CPUs and memory) and network requirements (guaranteed bandwidth and specific network topology). Moreover, a VI can be allocated anywhere atop a network datacenter, and because of its NP‐hard complexity, the search for optimal solutions has a limited applicability in cloud providers as requesting users seek an immediate response. The present work proposes an algorithm to accomplish the VI allocation by applying tree‐based heuristics to reduce the search space, performing a joint allocation of computing and network resources. So as to accomplish this goal, the mechanism includes a strategy to convert physical and virtual graphs to trees, which later are pruned by a grouped accounting algorithm. These innovations reduce the number of comparisons required to allocate a VI. Experimental results indicate that the proposed algorithm finds an allocation on feasible time for different cloud scenarios and VI topologies, while maintaining a high acceptance rate and a moderate physical infrastructure fragmentation. 相似文献
100.