关键字 |
| 马奈、文件共享、路由算法、文件的可用性。 |
介绍 |
| 马奈是一个广泛的网络。不同的主机节点存在。他们正在像路由器和相互通信的数据传输。有两种马奈,正常马奈和莫奈联系。首先有一个相对密集的节点分布在当地的区域而后者有稀疏分布式节点这一机会见面。当地的P2P模型提供了三个优势。首先,它使文件共享在没有基站可用(例如,农村地区)。其次,随着P2P架构,瓶颈在当前基于客户机-服务器文件共享系统超载的服务器是可以避免的。第三,它利用了否则浪费移动节点之间点对点的沟通机会。因为,节点可以自由访问和共享文件并参与分布式MANET环境,能够支持一些有趣的应用程序。 However the distinctive properties of MANETs, including node mobility, limited communication range and resource, have rendered many difficulties in realizing such a P2P file sharing system. File replication is an effective way to enhance file availability and reduce file querying delay. It creates replicas for a file to improve its probability of being encountered by requests. Unfortunately, it is impractical and inefficient to enable every node to hold the replicas of all files in the system considering limited node resources. Also, file querying delay is always a main concern in a file sharing system. Users often desire to receive their requested files quickly no matter whether the files are popular or unpopular. |
相关工作 |
| 5最大化可用性的移动ad hoc网络可以使用复制。如果有小数量的副本,文件共享不能有效。使用不同的文件复制协议但他们遭受有限的资源分配到不同的文件的问题,二是存储作为资源副本。提供的解决方案是全局最优文件复制。两个模型,如随机路点模型和基于社区的模型是用康陈[2]。在RWP,节点移动多次选择的点。所以会议每个节点的概率是相似的。随机获得的速度被认为是在这里。基于社区的流动模型的测试区域被分成不同的分区称为洞穴。每个洞都有一个社区。 One node belongs to one or more communities. When node moves into its home community it has a probability Pin and when a node visits foreign community it has a probability 1- Pin .In case of optimal file replication, the meeting ability of a node as the average number of nodes it meets in a unit time and use it to investigate the optimal file replication. The probability of being encountered by other node is proportional to the meeting ability of the node. It indicates that files residing in nodes with higher meeting ability have higher availability than files in node with lower meeting ability. While creating the replica the memory is occupied. The probability of being met by others is decided by the nodes meeting ability so replica consumes both storage resource and meeting ability of the node. |
| 根据Yu-Chee-Tseng[3]马奈的属性可以是动态变化的拓扑结构,没有基站支持和多次反射的沟通能力。交流他们使用跳跃的概念。当两个节点广播范围内时,他们互相交流使用单跳功能。这里讨论的问题是关于洪水的广播,广播风暴问题问题。对于这个重播可以做及时的基础上进行。广播是下游河段的问题能力、冗余、争用和碰撞。这些问题是本文中重温了广播问题,提高了实现能力和降低延迟和洪水。概率路由发现协议和文件[4],[6]是用来避免广播。他们查询转发到目的地节点概率较高的会议。另一个角度考虑将阈值。 Threshold is the constant defined which gives the fixed host density. In this paper dynamic solutions to those problems are given which includes adaptive counter-based, adaptive location based, and neighbor coverage schemes. In adaptive counter based scheme each individual has capability to change or adjust its threshold based on neighborhood status. In adaptive location based scheme a host choose its threshold based on its current value of neighbor for determining whether to broadcast or not. Neighbor coverage scheme uses the accurate neighborhood information. |
| Liangzhong阴[7]概念在移动自组网中协作缓存使用。不同的协作技术用于有效地访问数据。马奈的问题是基础设施。因此,数据传输从节点到节点路由器。当移动节点是请求转发路由器、带宽和功率可以保存,可以减少延迟。在合作缓存缓存数据的共享和协调是在多个节点来完成的。通过使用合作缓存web性能增加。方案,诸如CachePath, CacheData HybridCache使用。在CacheData,受欢迎的项目是在本地缓存。中间节点缓存数据,然后提供此数据为未来的请求。 For caching the data space is required. The problem with CacheData is that same data item can be cached at two or more nodes. Because of which there is wastage of large amount of cache. To avoid this problem, the rule used is that, a node does not cache data if all requests for the data are from same node. In CachePath intermediate node knows that which node has requested which data because the path of the requesting node and destination is saved in the cache. So when other node request for particular data item, the intermediate node calculate number of hops (distance) and then data item present on nearest node is served. Which means that it cache the data path. Because of which bandwidth and query delay can be reduced. For saving the path, there is no need to save all node information as the path from current router to the destination can be found by underlying routing algorithm. In Hybridcache cache path and cache data schemes are combined means that when a data tem needs to be cached it uses CacheData and path for that data item can also be cache. According to Huang et al. [9], WiFi-based wireless networks based on node mobility pattern, AP topology and file popularity, caching files in servers is done for realizing the optimal file availability to mobile users. However, the file servers considered are fixed nodes connecting to APs. |
| Pitkanen和奥特[10]提出了DTN存储模块利用DTN store-carry-and-forward paradigmand使DTN节点保持消息的副本转发所需要更长一段时间。在移动自组网主机自由地移动。的事情被认为是他们在一个范围&的范围,因为网络分区。所以从一个网络主机不能访问的日期从另一个网络项目。它降低了可访问性。复制的数据项的解决方案在移动主机不是业主原始数据。Hara的考虑[8],每个主机都有有限的内存空间为提高数据的可访问性。然后扩展的考虑非周期数据更新,因为在实际环境中认为是中尺度移动adhoc网络网络。在这里分享的数据项可以做到的。主机的数量出现在自组网访问数据项将被其他主机作为原件每个移动主机创建每个数据项的复制品&维护副本的内存空间。 No central server is present to determine the allocated replicas but mobile hosts asynchronously determine the allocation in a distributed manner as we know mobile hosts moves freely so some characteristics approaches need to be considered one is replicas are relocated in specific period, during every replications period replicas allocate is determined based on the access frequency from each mobile host to each data item & consideration of network topology is optional. Three replica allocation methods considered here are Static access frequency, DAFN Method, DAG. SAF allocates the replica of data items based on its own access. Frequently used item is replicated at host. The replica creation is done only when a data access to the data item is successful or the mobile host connected to other mobile host which host replica or original data. The problem with SAF is that every host has a replica which creates the memory problem is solved using DAFN. In this method replica duplication is avoided or eliminated among the neighbors of mobile hosts. The change with this scheme is that when replica duplication created frequency to data item changes the replica to another replica. In DAG the replica sharing is done on the lager group of mobile hosts than DAFN. The need for this is that network or group should be stable. |
| NCL魏高[11]提出的方案选择、上创建一个概率选择指标,为优化和协调多个缓存节点缓存数据的可访问性和开销之间的权衡。 |
工作范围 |
| 工作的范围可以扩展到: |
| 1。将文献综述不同方法最大化P2P文件访问可用性在移动Ad hoc网络复制和面向分布式路由协议。 |
| 2。的新框架和方法。 |
| 3所示。目前提出的实际仿真算法和评价其性能。 |
| 4所示。向现有的和拟议算法的比较分析为了效率 |
问题定义 |
| 虽然有不同的文件复制协议,他们的主要问题是缺乏一个规则将有限的资源分配给不同的文件副本创建以达到最小的全球平均查询延迟全球有限的资源下搜索效率优化。他们只是考虑存储的资源副本,但忽视,一个节点的频率也满足其他节点控制文件的可用性。文件节点具有更高会议能力有更高的可用性。所以现在的一个问题是,如何分配有限的资源在网络上复制到不同的文件,这样总体平均文件查询延迟最小化。 |
视角的解决方案 |
| 我们可以通过创建副本,以便改善文件共享路由效率增加。复制节点的存储能力和节点会议。资源分配的控制是平均查询延迟和最优文件复制规则,将资源分配给每个文件基于它的受欢迎程度和大小。这一个文件复制协议是基于规则,接近最低全球查询延迟完全分布式的方式。两个节点运动模型随机路径模型等正常断开连接的manet马奈和以社区为基础的流动模型可以提议休会有效的资源分配。由这个可以种植P2P系统的有效性。 |
讨论和未来的工作 |
| 上面讨论的方法有助于改善文件可用性使用复制技术,如随机路点正常马奈和基于社区为分布式MANET流动模型。当我们使用这两个模型效率增加和能源保存。我们可以扩展工作从理论上分析更复杂的动态环境,包括文件和动态节点查询模式。 |
确认 |
| 衷心感谢审查员的审查这个手稿,并提供输入的质量大大提高。 |
引用 |
- AshwiniS。Jagtap”即兴发挥P2PFile分享路由效率,“新兴趋势科技电脑科学的国际期刊,高雄,2014年问题11日。
- 康,“最大化P2P文件访问可用性在移动Ad hoc网络复制有效的文件共享,“2014人。
- y曾、美国Ni和e·施“自适应方法来缓解在无线多次反射移动ad hoc网络广播风暴,”在Proc。OfICDCS, 2001。
- b .奇亚拉、c·马可和et al .,“Hibop:机会网络路由协议的基础上,”,2007。
- a·林格伦a多利亚,o . Schelen“概率路由在间歇性地连接网络,”2003年。
- f·李和j·吴”,在容错拖把:提供基于内容的服务网络,“Proc. ICDCS, 2009。
- 阴和曹g . .“支持合作缓存特设网络,“TMC, 5卷,没有。1,2006。
- t . Hara和s . k . Madria”数据复制在特设网络,提高数据的可访问性“TMC, 2006。
- 黄y、y高和et al .,“优化文件检索延迟宽容的内容分发社区,“Proc. ICDCS, 2009。
- m . j . Pitkanen和j·奥特在移动dtn冗余和分布式缓存,”Proc. MobiArch, 2007。
- w·高g .曹、a . Iyengar和m . Srivatsa“支持合作缓存网络中断宽容。“Proc. ICDCS, 2011年。
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