The UMTS IMS network offers ip based multimedia applications with end-to-end QoS guarantee by using policy-based control principles. To support end-to-end QoS, the UMTS IMS network should be scalable, reliable and fle...
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As cellular packet data services become widely deployed by the rollout of the networks such as General Packet Radio Service (GPRS) and 3G cellular networks, packet-switched voice service such as voice over ip (Voip) c...
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ISBN:
(纸本)0780379748
As cellular packet data services become widely deployed by the rollout of the networks such as General Packet Radio Service (GPRS) and 3G cellular networks, packet-switched voice service such as voice over ip (Voip) can soon be expected to be offered as an alternative to circuit-switched voice service. While circuit-switched voice offers better quality, packet-switched voice offers better resource utilization due to its multiplexing and compression techniques that can be used in packet radio principle. Therefore, the capability of having voice service over either circuit-switched network or packet-switched network provides a tradeoff between voice quality and bandwidth utilization. This paper proposes three schemes that allow users to toggle between circuit-switched voice and packet-switched voice based on the desired tradeoff. The basic idea is to allow ongoing voice traffic to alternate between circuit-switched network and packet-switched network using a 3-way calling mechanism in the Sip-enabled GSM/GPRS cellular network. We also show how these toggle schemes can be used depending on the cell load. Detailed performances of the proposed schemes are evaluated using simulation with realistic parameters of a cellular environment. The result shows our schemes can alleviate cell overloading as well as provide the smooth transition of an ongoing call between circuit-switched network and packet-switched network. Our schemes can be easily deployed in any cellular mobile network where circuit-switched network and packet-switched network coexist.
The aviation industry continues to adopt Internet Protocol (ip) technology as the design basis for networking the functional domains both onboard and offboard commercial aircraft. The emerging network domains include ...
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ip Differentiated Services (DiffServ) has been standardized by the IETF and is considered as a promising IF QoS solution due to its scalability and ease of implementation. In this paper, we present a novel framework f...
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ip Differentiated Services (DiffServ) has been standardized by the IETF and is considered as a promising IF QoS solution due to its scalability and ease of implementation. In this paper, we present a novel framework for ip Differentiated Services (DiffServ) over optical burst switching (OBS), namely, DS-OBS. We present the network architecture, functional model of edge nodes and core nodes, the control packet format, a novel burst assembly scheme at ingress nodes and scheduling algorithm of core nodes. The basic idea is to apply DiffServ capable burst assembly at ingress nodes and perform different per hop behavior (PHB) electronic treatment for control packets of different QoS classes service at core nodes. Simulation results show that the proposed schemes can provide the best differentiated service for expedited forwarding (EF), Assured forwarding (AF) and best effort (BE) service in terms of end-to-end delay, throughput and ip packet loss probability.
Optical Burst Switching(OBS) was proposed as a scheme to switch bursty traffic on optical switches. However, due to the lack of optical RAM, the provision of QoS with OBS is an open issue. In this paper, we are the fi...
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ISBN:
(纸本)7563506861
Optical Burst Switching(OBS) was proposed as a scheme to switch bursty traffic on optical switches. However, due to the lack of optical RAM, the provision of QoS with OBS is an open issue. In this paper, we are the first to propose and demonstrate a practical QoS scheduling algorithm for ip/WDM networks based on OBS. We show that, by adopting a carefully designed rescheduling scheme using delayed preemption and controlled deadlines, we archive the goal of providing differentiated services without degrading the system performance.
This paper introduces a new hybrid routing method (HRM) for ip network traffic engineering. In this method, the traffic from some source/destination pairs is routed via MPLS constraint-based routing, while the remaini...
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This paper introduces a new hybrid routing method (HRM) for ip network traffic engineering. In this method, the traffic from some source/destination pairs is routed via MPLS constraint-based routing, while the remaining traffic is routed via conventional IGP routing. The method has been used to implement a HRM traffic engineering tool. The tool enables network operators to visualize and manage traffic to avoid congestion, as well as to decide where to place MPLS tunnels. Simulation results indicate that our HRM normally needs just a small number of tunnels to achieve a network performance that is comparable to that of fully meshed MPLS model.
Generalized multiprotocol label switching (G MPLS) is maturing to shape the next-generation mobile broadband ipnetworks, which will accommodate diverse technologies and various systems together. The link management p...
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Generalized multiprotocol label switching (G MPLS) is maturing to shape the next-generation mobile broadband ipnetworks, which will accommodate diverse technologies and various systems together. The link management protocol (LMP), launched under the GMPLS context and being standardized by IETF, is designed for managing traffic-engineering (TE) links and verifying the reachability of control channels. A detailed study of the latest Internet-draft on LMP has been conducted. Two important flaws in two of the four constituent procedures for LMP have been pointed out and improved by us in this paper. With regard to the link connectivity verification procedure, a batch-mode scheme is designed for enhancing its performance, scalability and flexibility, with theoretical analyses. In respect of the control channel management, a privileged hello protocol is introduced to evade the dead-loop malfunction.
The proceedings contain 42 papers. The special focus in this conference is on Network control and Engineering for QoS, Security and Mobility. The topics include: Policy based access router selections and context trans...
ISBN:
(纸本)9781475759488
The proceedings contain 42 papers. The special focus in this conference is on Network control and Engineering for QoS, Security and Mobility. The topics include: Policy based access router selections and context transfers in mobile ipnetworks;policy based management of wireless networks;implementing a VPN service with policy rules;adaptive segment path restoration (ASPR) in MPLS networks;security and resource policy -based management architecture for ALAN servers;a policy -based approach to firewall management;policy -based management with active networks;robust implementation of policies using ant-like agents;a solution for telecommunication network simulation;a policy -based bandwidth resource provisioning architecture;performance of a multi-tiered policy-based management system;a simple performance policy management environment;a distributed policy approach in support of multimedia session establishment;the design and implementation of policy-based bandwidth billing system;improvement of performance in MPLS domains by using caching and aggregation of CR -LSP;a tool to monitor the network quality of service;a novel two-step MPEG traffic modeling algorithm based on a GBAR process;media switch for multimedia services;building intelligent traffic engineering solutions;generalized processor sharing scheduling enhancement through session decomposition;an API for advanced trafficcontrol in DiffServ routers;better early packet discard;per-flow signalling extension across DiffServ domains;policy -driven model for security management;a pervasive view in distributed mobile computing;an approach for the deployment of set over WAP mobile networks;adaptive low priority packet marking for better TCP performance;a solution for improving TCP performance over wireless links and enhanced bandwidth estimation algorithms in the TCP congestion control scheme.
This paper presents performance data for a new hybrid routing method (HRM) for ip network traffic engineering. In this method, the major traffic streams between some source/destination pairs is routed via MPLS constra...
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This paper presents performance data for a new hybrid routing method (HRM) for ip network traffic engineering. In this method, the major traffic streams between some source/destination pairs is routed via MPLS constraint based routing, while the remaining traffic is routed via conventional IGP routing. When Internet traffic is heavy-tailed distributed, consisting of a few "elephant" and many "mice" flows, our traffic engineering results indicate that our HRM normally needs just a small number of tunnels to achieve a network performance that is comparable to that of fully meshed MPLS network. The method has been used to implement a HRM traffic engineering tool. The tool enables network operators to visualize and manage traffic to avoid congestion, as well as to decide where to place MPLS routers and tunnels.
This paper presents a summary of our work on developing an architecture for transporting real-time traffic (MPEG4 video in this paper) in ipnetworks that provide service differentiation. We target our architecture at...
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ISBN:
(纸本)0780378024
This paper presents a summary of our work on developing an architecture for transporting real-time traffic (MPEG4 video in this paper) in ipnetworks that provide service differentiation. We target our architecture at Assured Forwarding (AF) style services. This architecture assumes loss differentiation in the network and the network's ability to provide ECN messages to the sender. We did not consider policing/shaping at the edge routers. Rather we considered a more general case where marking and flow control are provided at the senders. For this network model, we developed a rate adaptation algorithm that can operate in both unicast and multicast applications with a minor modification. The simulation results presented in-this paper represent the multicast case., The results show how the rate adaptation algorithm accommodates different receivers with different networking capabilities and provides them with different qualities by taking advantage of the queue management capabilities of the AF service. We also show the results of testing this architecture with different AF queuing mechanisms, namely RIO and WRED.
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