As the Internet Protocol Television (IPTV) technology advances, IPTV services and customers increase. To attract more customers to raise profits, IPTV service providers usually launch many kinds of sales plans at the same time. Each sales plan has its own billing processing program so that the service subscription events are properly charged. Traditionally, sales plans are packaged case by case and billing processing programs are designed individually. However, the labor cost and time requirement augment as the number of sales plans increases. Therefore, how to gain working efficiency is obviously an important issue. In this paper, we propose a product management system that systematizes the packaging and programming procedure. The system, developed in modules, is flexible in the sense that similar sales plans, e.g. the plan of buy 3 get 1 free and the plan of buy 4 get 2 free, can be packaged by the same module with different parameter assignment. Existing packaging modules are reusable and new packaging modules can be added when needed. With the product management system, IPTV service providers can reduce their maintenance cost significantly.

With low Peak-to-Average Power Ratio (PAPR), Single Carrier ¡V Frequency Division Multiple Access (SCFDMA) is adopted by 3GPP to be the uplink access method of the LTE system. SC-FDMA allocates continuous Resource Blocks (RBs) to each subscriber to reduce PAPR. However, the continuous RB allocation degrades the flexibility in resource allocation. How to efficiently allocate radio resource in the SCFDMA scheme has been a critical issue. This paper proposes a scheduling algorithm concerning user satisfaction in LTE uplink radio resource allocation. The proposed algorithm is a generalization and an improvement of the well-known Mean Enhanced Greedy (MEG) scheduling algorithm. The simulation results show that the proposed algorithm achieves not only higher user satisfaction degree but also better fairness between subscribers than the MEG scheduling algorithm and a related algorithm, called the Recursive Maximum Expansion (RME) algorithm, no matter the desired uplink transmission rates among subscribers are the same or not.

Due to the flexibility and simplification, the fuzzy logic control (FLC) is chosen to make effective utilization of resources. The proposed Algorithm is divided into four parts: traffic classification, resource estimation for reservation, admission control and RAT selection. This combined fuzzy logic and multi-attribute decision making (MADM) based algorithm can make proper initial RAT selection, horizontal handoff, vertical handoff, admission control and load balancing. The MADM based RAT selection also has better efficiency than the traditional RRM mechanisms. By considering three kinds of traffic, voice, video and data respectively, the proposed scheme provides lower new call blocking probability and handoff call dropping probability in the heterogeneous wireless network that includes GERAN (GSM/EDGE Radio Access Network), HSPA (High-Speed Packet Access) and Mobile WiMAX (Worldwide interoperability for microwave access) RATs.

The IEEE 802.11p architecture imposes a demand- ing reliable transmission requirement on both road-side-unit (RSU) and on-board-unit (OBU) in order to provide emergency messages, traffic information, and internet services. The IEEE 802.16e network, which has been designed as a centralized control system to provide the mobile services in a metropolitan area network (MAN), can assist the WAVE network to fulfill the requirement. As all OBUs equip with both IEEE 802.11p and IEEE 802.16 transceivers, the deficiency of the IEEE 802.11p contention-based medium access control protocol can be curbed by using the IEEE 802.16e centralized scheduling scheme. As a solution, we propose a novel scheme, namely coordinated scheduling scheme (CSS), which allows the IEEE 802.11p OBUs to access service channels in a contention-free manner by means of IEEE 802.16 centralized scheduling. As confirmed by the performance evaluation, the proposed CSS can achieve significant throughput improvement, as compared with the IEEE 802.11p standard.

The wireless access in vehicular environment (WAVE) architecture of intelligent transportation system (ITS) has been standardized in the IEEE 802.11p specification and it is going to be widely deployed in many roadway environments in order to provide prompt emergency information and internet services. A typical WAVE network consists of a number of WAVE devices, in which one is the road-side-unit (RSU) and the others are on-board-units (OBUs), and supports one control channel (CCH) and one or more service channels (SCH) for OBUs to access. The CCH is used to transport the emergency messages and service information of SCHs and any SCH is used to carry internet traffic of OBUs. However, the IEEE 802.11p contention-based medium access control protocol would downgrade transmission efficiency when the number of OBUs served by a RSU is large and all WAVE devices equipped with a single transceiver access to the same SCH. Synchronizing all WAVE devices to periodically and equally access the CCH and an SCH will cost as much as 50% channel resource wastage on SCH. As a solution, we propose an efficiency-improvement scheme, namely agent-based scheduling (ABS) scheme, which promotes the SCH throughput by means of choosing one OBU to be the agent to schedule the other OBUs contending the access opportunities on one SCH to access the other SCH served by RSU in a contention-free manner. Numerical results and simulation results demonstrate that the proposed scheme indeed improves the standard transmission efficiency.

Wireless access in vehicular environment (WAVE) architecture of intelligent transportation system has been standardized in the IEEE 802.11p specification. The WAVE network supports the features of multi-rate and multi-channel and it is going to be widely deployed in realistic roadway environments in order to provide traffic information and convenient services. However, the adopted contention-based medium access control protocol, which confronts the performance anomaly problem, would severely downgrade transmission efficiency between road-side-unit (RSU) and on-board-unit (OBU) because they may use diverse data transmission rates to access channel. As a solution, this paper proposes the vehicular channel access scheme (VCAS) to group a number of OBUs with similar transmission rates into one channel to optimize the channel throughput, while the group sizes of channels are controlled in order to fulfill the fairness requirement. To flexibly compromise the tradeoff between throughput and fairness, a marginal utility model is proposed in this paper. Simulation results demonstrate that the proposed VCAS with marginal utility provides a flexible way to handle versatile vehicular scenarios.

The mobile wireless metropolitan area network (WMAN) architecture imposes a demanding power management requirement on mobile stations (MSs) in order to prolong the lifetime of MS. The base station (BS) will functionally serve as a buffer for non-real-time traffic distribution to the multiple MSs associated with it, and thus naturally provide MSs with the power saving capability. However, the power management scheme in IEEE 802.16e standard, which was designed for handling sleep pattern of non-real-time traffic, often use timeout approach to trigger sleep mode, as a certain idle time prior entering sleep mode will render a potential latency and limit the overall power saving capacity. Moreover, the fast growing sleeping window would cause long packet reception delay. As a solution, we propose a new scheme, namely listening interval spreading approach (LISA), which redistributes the idle periods and a number of interim listening periods in order to reduce the response time of interactive traffic, such as HTTP applications. As confirmed by the performance evaluation, the proposed LISA can achieve significant response time reduction as well as better power saving efficiency than standard.

The UMTS specification adopts the PQ/WFQ (priority queue/weight fair queue) scheduling where the PQ scheduling is used to provide a low-latency dedicated service for conversational and steaming traffic and the WFQ scheduling is used to provide relative delay service for interactive and background classes. In this article we propose a HPS (hierarchical packet scheduling) mechanism to enhance the performance of packet scheduling on the UMTS network. In this article we proposed the HPS scheduler and found that using the HPS performs better than the PQ/WFQ from simulation results.

The MIPv6 has been proposed to solve the problem of mobility in mobile networks by handling routing of IPv6 packets to mobile nodes that handover across the visited and home networks. However, the MIPv6 introduce long handover delay and signaling load. The HMIPv6 can solve the problem by splitting the handover management to macro-mobility and micro-mobility schemes. Although much research was focused on modified MIPv6 to get better efficient performance, there are few papers to discuss admission control when considering handover and mobility management. In this paper, we extend HMIPv6 binding update message to support CAC schemes. These CAC schemes can reduce the probability of the handoff dropping and cell overload, and limit the new call blocking probability. We also propose our schemes to a realistic scenario in integrated Wi-Fi and WiMAX networks.

The paper presents the performance modeling, analysis, and simulation of SIP-T (Session Initiation Protocol for Telephones) signaling system in carrier class VoIP (Voice over IP) network. The SIP-T signaling system defined in IETF (Internet Engineering Task Force) draft is a mechanism that uses SIP (Session Initiation Protocol) to facilitate the interconnection of PSTN with carrier class VoIP network. Based on IETF, the SIP-T signaling system not only promises scalability, flexibility, and interoperability with PSTN but also provides call control function of MGC (media gateway controller) to set up, tear down, and manage VoIP calls in carrier class VoIP network. In this paper, we analyze the queueing size (i.e. buffer size), the mean of queueing delay, and the variance of queueing delay of SIP-T signaling system that are the major performance evaluation parameters for improving QoS (quality of service) and system performance of MGC in carrier class VoIP network focused on toll by-pass or tandem by-pass of PSTN. First, we assume a mathematical model of the M/G/1 queue with non-preemptive priority assignment to represent SIP-T signaling system. Second, we present the formulas of queueing size, queueing delay, and delay variation for the nonpreemptive priority queue by queueing theory respectively. Besides, some numerical examples of queueing size, queueing delay, and delay variation are presented as well. Finally, the theoretical estimates are shown to be in excellent consistency with simulation results.

The combination of macrocells and microcells in a two-tier cellular system is attractive because it provides a balance between maximizing the number of users per unit area and minimizing the network control associated with handoff. In this paper we study system capacity of a two-tier cellular architecture employing 3 TDMA/CDMA strategies. Both the uplink and downlink are evaluated via mathematical analysis. It shows that system performance degrades for larger macrocells or microcells and the capacities are poor for users near the macrocells' boundary. It also shows a huge discrepancy between the results obtained for the center cell versus those obtained for the boundary cell.

The CDMA system has the potential to provide more capacity than other systems and the hierarchical layer of cells will be popular in the future. However, the problem is whether the same RF channels used in CDMA overlayed/underlayed macrocell and microcell structures also obtain high capacity as in the homogeneous structure. This paper will investigate the uplink and downlink interference of microcell and macrocell systems under hierarchical conditions. The pilot signal and power control for downlinks are also considered. We use analytical and simulation methods to investigate the problem. However the results are discouraging. The capacity of microcells and macrocells is limited by the downlink and uplink respectively.

In this paper, we study the performance of quality-based voice/data CDMA system where new and handoff traffic are considered. A call request for handoff data queues up if the signal-to-interference ratio exceeds a predefined threshold while priority is given to handoff voice calls by reserving some channels exclusively for them. The transmission power of voice and data users may be different. Important performance measures of the system such as blocking probability and system capacity for voice or data calls for different schemes are compared.