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Performance evaluation shows that Hierarchical Mobile IPv6 (HMIPv6) cannot outperform standard Mobile IPv6 (MIPv6) in all scenarios. Thus, adaptive protocol selection under certain circumstances is desired. Moreover, the registration cost of HMIPv6 needs to be reduced further. However, the performance of existing mobility based schemes is limited because they all neglected the traffic parameter of the mobile node (MN). In this paper, we propose an efficient three-level hierarchical architecture for HMIPv6 networks, in which an MN may register with either a higher/lower Mobility Anchor Point (MAP) or its home agent. By analyzing the inter-domain registration cost function, we obtain a novel parameter for MAP selection, which takes both the mobility parameter and the traffic parameter of an MN into account to minimize the overall registration cost. Simulation results show that normally the novel MAP selection algorithm achieves 25% percentage reduction of registration cost over the traditional mobility based algorithm. In addition, this algorithm obtains better performance when the mobility parameter and the traffic parameter of the MN vary. [ABSTRACT FROM AUTHOR]

Video traffic predicting and modeling are very important for compressed video transmission. The traditional method delineates the process by a rigid model with several parameters, which are difficult to estimate. In this paper, the MPEG-4 VBR (Variable Bit Rate) video traffic is modeled by the ANFIS (Adaptive Neuro-Fuzzy Inference System). Then, it is applied to modeling and predicting the MPEG-4 VBR video traffic. Simulations show the GoP (Group of Pictures) loss probabilities in actual video traffic are very close to those in ANFIS modeling traffic at the same experimental conditions and the prediction errors (1/SNR) are very small. [ABSTRACT FROM AUTHOR]

In this paper a new early detection algorithm for all-zero coefficient blocks before integer transformation and quantization is proposed in very low bit rate video coding for H.264/AVC standard. The all-zero detecting threshold is very critical as a tradeoff between encoder complexity and image quality. So firstly a feasible threshold range is analyzed theoretically, then based on extensive experiments on typical video sequences from the statistical opinion, a better optimal threshold is discussed, which has a better balance than the theoretically optimal threshold between mis-justice and leak-out ratio in detecting all-zero coefficient blocks. In our proposed algorithm, the sum of absolute difference (SAD) of each motion prediction error in the inter block is used, and this SAD is a bypass obtained from motion estimation process, so no additional computation is required. The simulation results show that the proposed algorithm can reduce the computational load significantly, almost without video quality loss. [ABSTRACT FROM AUTHOR]

A "Crossover Router" (CR) based QoS provisioning mechanism under an enhanced "Fast Handovers for Mobile IPv6" (FMIPv6) architecture has been proposed to provide better performance for multimedia applications in Mobile IPv6 (MIPv6) networks. In the proposal we extend the FBU and HI messages to notify the QoS requirement of "Mobile Node" (MN). Advance reservations along the possible future-forwarding paths are performed only between CR and MN to reduce reservation hops and signaling delays. In this paper we present the detailed performance evaluation results of this scheme compared with "Mobile RSVP" (MRSVP) protocol, using the network simulator (NS-2). In the simulations RSVP signaling cost, total bandwidth requirements, RSVP signaling and data packet delay in different scenarios of both schemes were considered. Results show that the proposed scheme for QoS guarantee has lower RSVP signaling cost and delay, as well as less bandwidth requirements in comparison with MRSVP. Furthermore, fluctuation and peak values of data packet delays in different scenarios are much lower. [ABSTRACT FROM AUTHOR]