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IP多媒体子系统自从3GPP UMTS Release5后已经被加入到通用移动通信系统(UMTS)的核心网络中.现在,UMTS网络主要包含以下3个域:电路交换(CS)、分组交换(PS)和IP多媒体子系统(IMS).IMS需要同原有相对陈旧的网络电路交换(CS)网络及公用电话交换网(PSTN).本文主要针对IMS同PSTN/CS网络的互通进行了概述. 相似文献
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WiMAX, a fourth-generation wireless-access technology, has made significant progress both in the standard forums and with wireless network carriers. To ensure service continuity to a legacy end user, it is important for a WiMAX mobile device to interwork with existing thirdgeneration access networks before it is uniquely and ubiquitously deployed. This article addresses this issue and shows how interworking can be achieved with EVDO wireless-access technology, using mobile IP in a dual mode terminal. We present a network architecture solution and detailed call flows. 相似文献
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Internetworking connectionless and connection oriented networks 总被引:2,自引:0,他引:2
《Communications Magazine, IEEE》1999,37(12):130-138
The use of connection-oriented (CO) networks for the transport of IP traffic is seen to have value to both users and service providers. Given the expectation that most endpoint-generated traffic will be in the form of connectionless (CL) IP datagrams, we address the problem of how to internetwork a CL (IP) network with a CO network. CO networks can be packet-switched or circuit-switched. Examples of packet-switched CO networks include ATM and MPLS networks, in which resource reservations are made at the ATM or shim layer, and IP-switch-based networks, in which resource reservations are made at the IP layer. Examples of circuit-switched networks include SONET/SDH and WDM networks that consist of programmable optical crossconnects. We consider the internetworking problem for two modes of operation of CO networks: provisioned, in which connections are set up a priori, and switched, in which connections are set up on demand. The main focus of this article is on the more complex problem: the internetworking of CL IP networks with CO networks operated in a switched mode. Our solution consists of (i) interworking user plane protocols with protocol conversion in some cases instead of always using protocol encapsulation, (ii) interworking routing protocols by either simply having gateways know routing information of both networks or having all nodes know routing information of both networks, and (iii) interworking signaling protocols by using application- or transport-layer end-to-end handshakes to trigger connection setups through the CO network. We demonstrate throughput improvements with our integrated routing interworking scheme over the MPOA IP-ATM internetworking solution for two example networks 相似文献
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Introducing a novel authentication protocol for secure services in heterogeneous environments using Casper/FDR
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Next generation network is a convergence of networks such as 2G/3G, WLAN as well as the recently implemented Long Term Evolution networks. Future mobile devices will switch between these different networks to maintain the connectivity with end servers. However, to support these heterogeneous environments, there is a need to consider a new design of the network infrastructure, where currently closed systems such as 3G will have to operate in an open environment. Security is a key issue in this open environment; after authenticating the mobile terminal to access the network, there is a requirement for service‐level mechanisms to protect the session between the mobile terminal and the remote service provider. Furthermore, because mobile terminals switch between networks of different characteristics in terms of coverage, quality of service and security, there is a need for reassessing the security of the same session over the different networks to comply with the changes at the network level due to the mobility. Therefore, this paper introduces a service‐level authentication and key agreement protocol to secure the session between the mobile terminal and the end server. The proposed protocol considers user mobilities in a heterogeneous environment and reassesses the session's security level in case of handover. The proposed protocol has been verified using formal methods approach based on the well‐established Casper/FDR compilers. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Third-generation cellular networks have been designed to provide a variety of IP data services. Both IPv4 and IPv6 are supported in order to provide future-proof solutions. Mobility is supported through both cellular-specific and IP mechanisms. Mobile IP is becoming a key technology for managing mobility wireless networks. At the same time, the session initiation protocol is the key to realizing and provisioning services in IP-based cellular networks. The need for mobility of future real-time service independent of terminal mobility requires SIP to seamlessly interwork with mobile IP operations. In this article, we investigate the issues related to interworking between SIP and mobile IP, with a focus on IPv6 and the applicability to 3G networks being standardized in 3GPP and 3GPP2. 相似文献
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Rapid growth in use of the Internet at and away from the workplace has spurred tremendous interest in the provision of anytime-anywhere network connectivity to mobile users. Commonly studied mobility scenarios involve users equipped with portable data terminals roaming around at slow to moderate speeds within a coverage area. Mobile IP and wireless ATM are examples of protocols designed for providing network connectivity to such mobiles in IP and ATM networks. A different application involving mobile multi-user platforms (MMUP) equipped with onboard private ATM networks is discussed in this article. Examples of such mobile platforms include airplanes, trains, and ships. The presence of an onboard network, multiple users, and potentially high speed of travel presents unique challenges in provision of internetwork connectivity to these MMUPs. Specific characteristics of MMUPs, architectural issues in design of the underlying cellular network, subnetwork mobility within ATM internetworks, location management of MMUPs, and multi-user connection handoffs on MMUP moves are the main issues addressed in the article. Network architectures and protocols developed for terminal mobility scenarios are evaluated for applicability in the present context, and new solutions are presented for problems unique to the MMUP application scenario 相似文献
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Extending Global IP Connectivity for Ad Hoc Networks 总被引:1,自引:0,他引:1
Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed. 相似文献
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Dynamic satellite system QoS architecture integrated with IP Multimedia Subsystem core network
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Cédric Baudoin Mathieu Gineste Chaput Emmanuel Patrick Gelard Julien Bernard 《International Journal of Satellite Communications and Networking》2015,33(3):217-239
Convergence is one of the most important challenges for Next Generation Networks (NGN). This includes service convergence as well as fixed‐mobile convergence. The integration of satellite telecommunication system into NGN is a key to increasing the coverage of future networks and opening satellite access networks to a wider range of terrestrial solutions. Digital Video Broadcast (DVB) Return Channel via Satellite system (DVB‐RCS) and its evolution (DVB‐RCS2) are widely used European standards that are specified for broadband satellite systems using dynamic capacity assignment and multifrequency TDMA. This paper introduces a new QoS architecture derived from terrestrial IP Multimedia Subsystem solutions to provide advanced end‐to‐end QoS support, and defines cross‐layer optimization paths suited to the satellite context and in particular using DVB standards. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Linoh A. Magagula H. Anthony Chan Olabisi E. Falowo 《Wireless Communications and Mobile Computing》2012,12(16):1414-1428
Next generation wireless networks (NGWN) will be an integration of heterogeneous wireless access networks that will interwork over an IP‐based infrastructure. This all‐IP vision has led to the development of handover mechanisms to support seamless mobility for active network services among the different interworking wireless networks in order to ensure network access ubiquity in NGWN. These handover mechanisms need to ensure that mobile devices continue to receive ongoing communication without any noticeable disruption during handover events among the heterogeneous networks. This paper gives a qualitative and quantitative review of current handover approaches of IP mobility management protocols for NGWN with an objective to introduce a new way of further optimizing the handover performance. In particular, the paper focuses on handover approaches of mobile IPv6 (MIPv6) based mobility management protocols. Thus, the need, benefits, and limitations of these handover approaches are explored. Thereafter, dynamic handover coordination is introduced as a new viable solution that exploits the benefits and mitigates the limitations of these handover approaches hence improving handover performance in terms of handover delay, packet loss, and signaling overhead. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Mobile evolution from the second generation (2G) to the third generation (3G) raises several important questions for operators and manufacturers. How to ensure that the old and current investments can still be utilized in the future? What is the optimum architecture? ATM or IP? Voice or data? There is no single correct answer to these questions, as it all depends on individual cases. In this paper, we discuss the transport architecture evolution for the universal mobile telecommunications system (UMTS)/international mobile telecommunications—year 2000 (IMT‐2000), or 3G cellular networks and interworking aspects between 2G and 3G cellular networks. The interfaces between access nodes in a cellular network and the changes incorporated to support packet data services are described. Emerging services such as mobile data, virtual private networks (VPN) and location aware networking are described. Role of ATM and IP in this new transport architecture is presented. Control and data plane interworking issues between different transport technologies are described. The new ATM standard, ATM adaptation layer type 2 (AAL2) and its applicability for transporting compressed speech in an ATM based cellular network is described. A similar approach in IP, multiplexing in real‐time transport protocol (RTP) payload to transport compressed speech on selective interfaces of 3G network, is introduced. Transport network architecture evolution within four different scenarios is evaluated. Special interest is focused on the protocol stacks and flexible layered solutions that allow smooth migration from one transport technology to another. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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Giuseppe Araniti Antonio Iera Antonella Molinaro 《Wireless Personal Communications》2010,54(1):137-153
Digital Video Broadcasting for Handheld terminals (DVB-H) is a new standard developed by DVB Project consortium to enable the delivery of broadcast transmissions to mobile terminals (such as, cellular telephone, PDA, pocket PC, etc.). Being the DVB-H network characterized by a cellular structure, a key issue to avoid the service interruption in these systems is the design of effective handoff procedures. This paper introduces a novel seamless handoff approach for DVB-H networks, which is designed to reduce the user terminal power consumption and to make the handoff algorithm be driven by the quality of the user received signal. This implies the adoption of a method based on the constant monitoring of the Modulation Error Rate (MER), instead of standard RSSI-based procedures. Additional advantages in terms of power saving derive from the use of an Active Handoff procedure that exploits the UMTS return channel as an interaction channel. The proposed scheme has been successfully tested and obtained results make us confident that this can be an interesting research direction to investigate in the view of effective DVB-H handoff protocol design. 相似文献
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Sarantis Paskalis Alexandros Kaloxylos Evangelos Zervas Lazaros Merakos 《Mobile Networks and Applications》2003,8(3):197-207
During the past years, several attempts have been made to develop functionality for mobility management support and QoS provision in the realm of the IP networks. Since IP was not designed to support such functionality, new protocols have been specified and implemented to tackle these issues. Mobile IP is currently the dominant protocol that allows users to retain connectivity while roaming in IP networks. RSVP (Resource reSerVation Protocol) is a well established protocol for reserving network resources to support QoS requirements. These protocols, when deployed separately, can work quite efficiently. However, if their functionality is combined, several inefficiencies arise in terms of QoS deterioration and misuse of the network resources. To minimize these inefficiencies, we propose a new approach that limits mobility and QoS related network modifications inside the domain, in which a user moves. The deployment of our scheme enhances the network resource usage efficiency, while minimizing the duration of the QoS deterioration experienced after a terminal movement. To quantify the advantages of our proposal, we have developed an analytical and a simulation model that we also present in this paper. 相似文献
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Wanjiun Liao Jen-Chi Liu 《Communications Magazine, IEEE》2000,38(4):70-75
This article explores VoIP mobility in the context of IP and cellular networks interworking. ITU-T Rec. H.323 gateways provide the interconnection between IP networks and switched circuit networks. They allow a call originating from an SCN phone to be transmitted over an IP network to an H.323 terminal, or bridged to another SCN phone. While H.323 provides interoperability with other SCN terminals, the major efforts have been focused on IP/wired SCN (PSTN, ISDN, etc.) interworking. In this article we discuss the challenges associated with the interworking between IP networks and cellular networks through H.323 gateways, and propose an innovative approach using the existing call transfer supplementary service to provide VoIP mobility in the H.323 IP telephony networks. The proposed approach uses existing components in the H.323 standard, thereby allowing VoIP mobility service in hybrid IP/cellular networks to be a value-added feature in the existing H.323-compliant Internet telephony systems 相似文献
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从江都市有线数字电视广播系统的DVB前端的设计与组建、条件接收系统(CAS)的设计与论证、电子节目指南(EPG)系统方案的设计、城域HFC接入网的频谱分配、用户终端DVB接收系统的设计等方面,介绍了符合江都市广播电视产业市场化发展需要的DVB—C系统方案。 相似文献
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Chan P.M.L. Sheriff R.E. Hu Y.F. Conforto P. Tocci C. 《Communications Magazine, IEEE》2001,39(12):42-51
The next generation in mobility management will enable different mobile networks to interoperate with each other to ensure terminal and personal mobility and global portability of network services. However, in order to ensure global mobility, the deployment and integration of both satellite and terrestrial components are necessary. This article is focused on issues related to mobility management in a future mobile communications system, in a scenario where a multisegment access network is integrated into an IP core network by exploiting the principles of Mobile IP. In particular, attention is given to the requirements for location, address, and handover management. In a heterogeneous environment, the need to perform handover between access networks imposes particular constraints on the type of information available to the terminal and network. In this case, consideration will need to be given to parameters other than radio characteristics, such as achievable quality of service and user preference. This article proposes a new approach to handover management by applying the fuzzy logic concept to a heterogeneous environment. The article concludes with a presentation of mobility management signaling protocols 相似文献
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Transmission-scheduling protocols can support contention-free link-level broadcast transmissions and delay sensitive traffic in mobile, multiple-hop packet radio networks. Use of transmission-scheduling protocols, however, can be very inefficient in mobile environments due to the difficulty in adapting transmission schedules. The paper defines a new adaptive and distributed protocol that permits a terminal to adapt transmission assignments to changes in topology using information it collects from its local neighborhood only. Because global coordination among all the terminals is not required and changes to transmission assignments are distributed to nearby terminals only, the protocol can adapt quickly to changes in the network connectivity. The two key parameters that affect the ability of the protocol to adapt to changes in connectivity are the rate of connectivity changes and the number of terminals near the connectivity changes. Using simulation, we determine the ranges for these parameters for which our adaptive protocol can maintain collision-free schedules with an acceptable level of overhead. The stability of the protocol is also characterized by showing that the protocol can quickly return to a collision-free transmission schedule after a period of very rapid changes in connectivity. Our channel-access protocol does not require a contention-based random-access phase to adapt the transmission schedules, and thus its ability to adapt quickly does not deteriorate with an increase in the traffic load. 相似文献