LNT: A logical neighbor tree secure group communication scheme for wireless sensor networks

Secure group communication is a paradigm that primarily designates one-to-many communication security. The proposed works relevant to secure group communication have predominantly considered the whole network as being a single group managed by a central powerful node capable of supporting heavy communication, computation and storage cost. However, a typical Wireless Sensor Network (WSN) may contain several groups, and each one is maintained by a sensor node (the group controller) with constrained resources. Moreover, the previously proposed schemes require a multicast routing support to deliver the rekeying messages. Nevertheless, multicast routing can incur heavy storage and communication overheads in the case of a wireless sensor network. Due to these two major limitations, we have reckoned it necessary to propose a new secure group communication with a lightweight rekeying process. Our proposal overcomes the two limitations mentioned above, and can be applied to a homogeneous WSN with resource-constrained nodes with no need for a multicast routing support. Actually, the analysis and simulation results have clearly demonstrated that our scheme outperforms the previous well-known solutions.     

Security issues and solutions in multicast content distribution: a survey

Multicast enables efficient large-scale content distribution by providing an efficient transport mechanism for one-to-many and many-to-many communication. The very properties that make multicast attractive, however, also make it a challenging environment in which to provide content security. We show how the fundamental properties of the multicast paradigm cause security issues and vulnerabilities. We focus on four areas of research in security for multicast content distribution: receiver access control, group key management, multicast source authentication, and multicast fingerprinting. For each we explain the vulnerabilities, discuss the objectives of solutions, and survey work in the area. Also, we briefly highlight other security issues in multicast content distribution including source access control, secure multicast routing, and group policy specification. We then outline several future research directions.     

基于消息认证码的安全有效的组播源认证

组播通信正成为不断增长的应用基础，而其关键是要为组通信提供可靠的安全机制，然而，现有的组播安全协议仅能提供部分的解决方法，考虑到源认证是组的最主要安全事务之一，文章基于消息认证码提出了一种安全有效的组播源认证方法。     

多点通信中的可靠性机制

多点通信可以实现组成员之间迅速有效的信息交换.可靠性是多点通信研究中的一个重要问题,其实现机制与点到点方式中有所不同.分析了多点通信可靠性方面所提出的新问题和解决方法,并简要介绍了一个实用性协议.     

Adaptive group multicast with time-driven priority

This paper shows how to provide an adaptive real-time group multicast (many-to-many) communication service. Adaptive means that the number of nodes that transmit to the multicast group is continuously changing. In order to meet deterministic quality-of-service (QoS) requirements of a real-time group multicast, some communication resources are reserved. We show (1) how bandwidth is reserved for each multicast group and (2) how an active source can dynamically share the bandwidth allocated to this multicast group with other active group members. Quality-of-service support for a real-time multicast group is based on time-driven priority. In this scheme the time is divided into time frames of fixed duration, and all the time frames are aligned by using a common global time reference, which can be obtained from the Global Positioning System. Bandwidth is allocated to a multicast group as a whole, rather than individually to each user. The allocation is done by reserving time intervals within time frames in a periodic fashion. This type of allocation raises two problems that are studied in this paper: (1) scheduling: how time intervals are reserved to each multicast group and (2) adaptive sharing: how the active (transmitting) participants can dynamically share the time intervals that have been reserved for their multicast group. The proposed approach is based on the embedding of multiple virtual rings, one for each multicast group. By using the virtual rings, it is simple to route messages to all the participants while minimizing the bound on the buffer sizes and queueing delays. The final part of this paper introduces a scalable growth of the multicast group by adding multiple subtrees to the virtual ring     

Efficient solutions to multicast routing in communication networks

An important problem in both wireless and wired communication networks is to be able to efficiently multicst information to a group of network sites. Multicasting reduces the transmission overhead of both wireless and wired networks and the time it takes for all the nodes in the subset to receive the information. Since transmission bandwidth is a scarce commodity especially in wireless networks, efficient and near minimum-cost multicast algorithms are particularly useful in the wireless context. In this paper, we discuss methods of establishing efficient and near minimum-cost multicast routing in communication networks. In particular, we discuss an efficient implementation of a widely used multicast routing method which can construct a multicast tree with a cost no greater than twice the cost of an optimal tree. We also present two efficient multicast tree constructions for a general version of the multicast routing problem in which a network consists of different classes of nodes, where each class can have one or more nodes of the same characteristic which is different from the characteristics of nodes from other classes. Because of their efficient running times, these multicast routing methods are particularly useful in the mobile communication environments where topology changes will imply recomputation of the multicast trees. Furthermore, the proposed efficient and near minimum-cost multicast routing methods are particularly suited to the wireless communication environments, where transmission bandwidth is more scarce than wired communication environments.Partially supported by NSF/LaSER under grant number EHR-9108765, by LEQSF grant number 94-RD-A-39, by NASA under grant number NAG 5-2842.     

一种分布式多源应用层多播方法

为满足以分布交互仿真为代表的大规模多数据源多播应用的通信需求,重点研究了大规模多源应用层多播问题,提出了大规模多源应用层多播问题模型。参考基于P2P覆盖网络的应用层多播方法Scribe和Bayeux,设计了一种适用于大规模多数据源多播应用的分布式多源应用层多播方法DMALMM。DMALMM采用随机邻居结点选择机制,使用反向寻径方法构建数据分发树。仿真试验表明,DMALMM方法的结果优于采用Scribe方法的结果,是一种有效的分布式多源应用层多播方法。     

Minimum-cost QoS multicast and unicast routing in communication networks

In this paper, we study the minimum-cost quality-of-service multicast and unicast routing problems in communication networks. For the multicast problem, we present an efficient approximation algorithm to find a balance between a minimum-cost multicast tree and a minimum-delay multicast tree, with a provably good performance under the condition that link delay and link cost are identical. For the unicast problem, we present an efficient primal-dual heuristic algorithm to find a path which balances path cost and path delay, together with an error bound. The lack of a provably good performance for the second algorithm is complemented by computational results on randomly generated networks. Our algorithm finds optimal solutions in more than 80% of the cases and finds close to optimal solutions in all other cases, while using much less time.     

CDMA2000系统中的广播和多播业务

在下一代移动通信系统中,CDMA2000有着广泛应用,其广播业务和多播业务又是整个系统的一个亮点。文章详细讨论了CDMA2000移动系统中的广播和多播业务的设计方式,重点讨论了设计中的网络、信令等方面内容,采用这种设计方式可实现不同内容点到多点的高效、可扩展的传送。指出了设计中可能遇到的问题,提出了相应解决方案。     

An integrated multicast connection management solution for wiredand wireless ATM networks

With the prospect of commercializing wireless ATM networks fast becoming a reality, and ATM becoming one of the main network technologies for multimedia computing, the design of ATM connection management solutions has to take into consideration these recent developments. Unfortunately, current ATM signaling solutions standardized by the ATM Forum have to be modified extensively in order to support wireless ATM. Furthermore, these solutions have not delivered a suitable multicast service which can support the communication requirements found in today's computer-based multimedia applications. The work described here therefore addresses these shortcomings by proposing a new multicast connection service architecture and its related algorithms. Some of the important concepts elaborated in the design include the notion of open signaling, the use of logical multicast groups to handle all connections, and seamless support for host mobility     

A QoS-aware multicast routing protocol

The future Internet is expected to support multicast applications with quality of service (QoS) requirements. To facilitate this, QoS multicast routing protocols are pivotal in enabling new receivers to join a multicast group. However, current routing protocols are either too restrictive in their search for a feasible path between a new receiver and the multicast tree, or burden the network with excessive overhead. We propose QMRP, a new QoS-aware multicast routing protocol. QMRP achieves scalability by significantly reducing the communication overhead of constructing a multicast tree, yet it retains a high chance of success. This is achieved by switching between single-path routing and multiple-path routing according to the current network conditions. The high level design of QMRP makes it operable on top of any unicast routing algorithm in both intradomain and interdomain. Its responsiveness is improved by using a termination mechanism which detects the failure as well as the success of routing without the use of timeout. In addition, QMRP always constructs loop-free multicast trees     

Deployment issues for the IP multicast service and architecture

IP multicast offers the scalable point-to-multipoint delivery necessary for using group communication applications on the Internet. However, the IP multicast service has seen slow commercial deployment by ISPs and carriers. The original service model was designed without a clear understanding of commercial requirements or a robust implementation strategy. The very limited number of applications and the complexity of the architectural design-which we believe is a consequence of the open service model-have deterred widespread deployment as well. We examine the issues that have limited the commercial deployment of IP multicast from the viewpoint of carriers. We analyze where the model fails and what it does not offer, and we discuss requirements for successful deployment of multicast services     

A ring-based multicast routing topology with QoS support in wireless mesh networks

Wireless mesh networking (WMN) is an emerging technology for future broadband wireless access. The proliferation of the mobile computing devices that are equipped with cameras and ad hoc communication mode creates the possibility of exchanging real-time data between mobile users in wireless mesh networks. In this paper, we argue for a ring-based multicast routing topology with support from infrastructure nodes for group communications in WMNs. We study the performance of multicast communication over a ring routing topology when 802.11 with RTS/CTS scheme is used at the MAC layer to enable reliable multicast services in WMNs. We propose an algorithm to enhance the IP multicast routing on the ring topology. We show that when mesh routers on a ring topology support group communications by employing our proposed algorithms, a significant performance enhancement is realized. We analytically compute the end-to-end delay on a ring multicast routing topology. Our results show that the end-to-end delay is reduced about 33 %, and the capacity of multicast network (i.e., maximum group size that the ring can serve with QoS guarantees) is increased about 50 % as compared to conventional schemes. We also use our analytical results to develop heuristic algorithms for constructing an efficient ring-based multicast routing topology with QoS guarantees. The proposed algorithms take into account all possible traffic interference when constructing the multicast ring topology. Thus, the constructed ring topology provides QoS guarantees for the multicast traffic and minimizes the cost of group communications in WMNs.     

A survey of proposals for an alternative group communication service

As expectations for the Internet to support multimedia applications grow, new services need to be deployed. One of them is the group communication service for one-to-many or many-to-many data delivery. After more than a decade of important research and development efforts, the deployment of multicast routing in the Internet is far behind expectations. Therefore, a first motivation for an alternative group communication service is to bypass the lack of native IP multicast routing. Although less efficient and scalable than native multicast routing, such alternative services are generally suitable for the purpose. A second possible motivation is to go beyond the limitations of classic multicast routing for very specific working environments. We identify, classify, and discuss some of these alternative approaches.     

一种基于时间结构树的多播密钥管理方案

随着Internet的发展,多播通信技术得到了广泛的应用.其中组密钥管理是多播安全的核心问题.文中在分析已有研究的基础上,提出了一种基于时间结构树的密钥管理方案,采用周期性的密钥更新机制,通过安全滤波器分配新的组密钥,大大减少了密钥更新时的传输消息,提高了密钥更新的效率,实现密钥更新的可靠性.     

一种短波通信可靠多播群组管理方法

针对异步短波单层可靠多播网络群组管理中临时节点加入或退出时网络处理时延较 长的问题,提出了一种分层可靠多播网络群组管理方法。通过设置群首节点来减少该临时节 点与网络内部成员的交互次数。理论分析和仿真结果表明,该方法较单层可靠多播网络群组 管理方法,具有网络对该临时节点处理时延小、群组管理复杂度低等优点,其应用前景广阔 。     

基于LKH混合树模型的新型组播密钥更新方案

安全组播是组播技术走向实用化必须解决的问题。在组成员动态变化时,设计一个高效的密钥管理方案是安全组播研究的主要问题。提出了一种基于新型混合树模型的组播密钥更新方案。该方案将GC的存储开销减小为4,同时,在成员加入或离开组时,由密钥更新引起的通信开销与nm保持对数关系(n为组成员数,m为每一族包含的成员数)。     

A protocol for scalable loop-free multicast routing

In network multimedia applications such as multiparty teleconferencing, users often need to send the same information to several (but not necessarily all) other users. To manage such one-to-many or many-to-many communication efficiently in wide-area internetworks, it is imperative to support and perform multicast routing. Multicast routing sends a single copy of a message from a source to multiple receivers over a communication link that is shared by the paths to the receivers. Loop-freedom is an especially important consideration in multicasting because applications using multicasting tend to be multimedia and bandwidth intensive, and loops in multicast routing duplicate looping packets. We present and verify a new multicast routing protocol, called multicast Internet protocol (MIP), which offers a simple and flexible approach to constructing both group-shared and shortest-paths multicast trees. MIP can be sender-initiated or receiver-initiated or both; therefore, it can be tailored to the particular nature of an application's group dynamics and size. MIP is independent of the underlying unicast routing algorithms used. MIP is robust and adapts under dynamic network conditions (topology or link cost changes) to maintain loop-free multicast routing. Under stable network conditions, MIP has no maintenance or control message overhead. We prove that MIP is loop-free at every instant, and that it is deadlock-free and obtains multicast routing trees within a finite time after the occurrence of an arbitrary sequence of topology or unicast changes     

一种适用于动态/移动环境的新的组播协议

组播协议由于能够有效的利用网络带宽并降低服务器的负担因而受到广泛的关注.其中的共享树组播协议由于具有良好的扩展性而得到更多的支持,然而目前的共享树组播协议在动态移动环境中的性能很差,一些改进协议(单核移动协议)虽然可以很好的提高原有协议的性能但是所需要的额外开销很大.针对这种情况,本文提出了一种新的共享树组播协议-动态多核协议,该协议能够根据组播成员的分布动态的渐进的调整组播树的形状,从而能够在低开销的情况下为移动用户提供良好的性能.计算机仿真和数学分析都表明动态多核协议要明显优于共享树组播协议和单核移动协议.     

Stateless overlay multicast with in-packet bloom filters

Due to the difficulty of deploying Internet protocol (IP) multicast on the Internet on a large scale, overlay multicast has been considered as a promising alternative to develop the multicast communication in recent years. However, the existing overlay multicast solutions suffer from high costs to maintain the state information of nodes in the multicast forwarding tree. A stateless overlay multicast scheme is proposed, in which the multicast routing information is encoded by a bloom filter (BF) and encapsulated into the packet header without any need for maintaining the multicast forwarding tree. Our scheme leverages the node heterogeneity and proximity information in the physical topology and hierarchically constructs the transit-stub overlay topology by assigning geometric coordinates to all overlay nodes. More importantly, the scheme uses BF technology to identify the nodes and links of the multicast forwarding tree, which improves the forwarding efficiency and decreases the false-positive forwarding loop. The analytical and simulation results show that the proposal can achieve high forwarding efficiency and good scalability.