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Since mobile devices are equipped with limited battery power, it is essential to have efficient power management mechanisms in mobile broadband networks such as mobile WiMAX that enable always on connectivity and provide high throughputs. In recent times Voice over IP (VoIP) has emerged as an important and dominant application in broadband mobile networks such as WiMAX. VoIP traffic is uniquely characterized...
Telecom based service providers are relentlessly trying to accelerate their service offerings to match the pace at which the users are embracing the Web. In reality IMS based Telecom and Internet based Web 2.0 networks have their own advantages and need to co-exist to create an enriched user experience. The convergence of IP Multimedia subsystem (IMS) based Telecom and Web 2.0 based networks is slowly...
IEEE 802.16e WiMAX standard classifies packets in the decreasing order of priority as UGS, RTPS, eRTPS, nRTPS, BE. This mechanism of classification is application dependent and a user will not be able to request for a change in priority even though higher priority traffic bandwidth might be available and the user is ready to pay more for elevation of low priority traffic to higher priority. We propose...
New generation multimedia applications over broadband wireless networks like WiMAX1 consume relatively large amount of battery power. Most of the studies in this field have been focused either on the power conservation or the video quality evaluation aspect of WiMAX based on early stage simulations. However, Network emulation studies are preferred during design phase to guide product designs. To the...
IEEE 802.16m amendment is being drafted to meet the 4G network requirements as an extension to 802.16e-2005. In 802.16e, a Subscriber Station (SS) can have multiple connections to a Base Station (BS) for supporting different services simultaneously. SS negotiates sleep-mode with BS by exchange of management information for one or more connections per active Power Saving Class Identifier (PSC_ID) belonging...
Radio link failure (RLF) is a common phenomenon in all radio access technologies like GSM or UMTS or wireless-LAN etc., when the radio channel signal strength is weak to continue with the application. RLF is a local event detected by mobile handset (or user equipment-UE) immediately and network nodes come to know later. It is also difficult to recover for the UE due to low signal. Hence, RLF has to...
Multi-hop relay based WiMAX architecture is one of the proposed solutions to connectivity in difficult terrains and an economical solution for developing/under-developed countries. This paper analyzes a hybrid multi-hop architecture consists of mesh and PMP both types of connections. Architecture for relay station (RS) has been proposed to provide such hybrid connectivity. Moreover, to provide end-to-end...
WiMAX standard's medium access control (MAC) protocol supports QoS for real time traffic. Single WiMAX can cover 10 Kms with broad band support of around 22 Mbps in downlink and 6 Mbps in uplink [7]. Multiple WiMAX base stations (BSs) are needed to cover a thickly populated city or county with large diameter (i.e., above 20 kms, which is very common). To maintain QoS for inter WiMAX BSs traffic, it...
Mobile stations (MS) with active UGS connections are usually not polled for their non-UGS data. If the MS wishes to be polled for non-UGS data then it needs to set the poll-me (PM) bit to 1 in the Grant Management Sub-header. The IEEE standard 802.16e describes the method of setting PM bit to 1. However, it does not specify when to turn this bit to 0. If it remains 1, then after transmission of non-UGS...
Broad band Wireless Access called WiMAX is becoming popular due to its support for QoS, in real time communication. To the best of our knowledge, the WiMAX base station (BS) schedules uplink (UL) and downlink (DL) packets station wise and within a station scheduling is done with respect to priority of services. In this process, while BS transmits packets of different priorities for a subscriber station...
In this paper a novel interoperability strategy and architecture is described that guarantees the quality of service (QoS) requirements for applications originating in IEEE 802.11e based WLAN to a serving IEEE 802.16 based WirelessMAN and vice versa. The architecture for mapping QoS requirements makes use of inherent MAC layer convergence flexibilities available in these networks along with features...
Power control is a key air-interface management mechanism for any multiple-access CDMA-based wireless air-interface. Typically it has been used to ensure a target packet-error-rate (PER) for any user connection. In the presence of hybrid-ARQ (HARQ) on the reverse link (as in 3GPP2's EVDO-Rev A), there is additional flexibility that a power control implementation can utilize to ensure quality-of-service...
In this paper, we propose Sniff and Embark (Sniff) protocol, a novel frame sniffing and token passing based approach to provide QoS in WLANs. Our simulations show that S^E performs significantly better than EDCF over the performance metrics - delay, jitter and time- constrained frame drop ratio.
The IEEE 802.11e standard defines the enhanced distributed coordination function (EDCF) to improve the quality of service (QoS) in a wireless local area network (WLAN). The EDCF is a CSMA/CA based protocol, where stations compete for the medium with prioritized contention parameters. Also defined in the 802.11e standard is the polling mode of the hybrid coordination function (HCF - polling), which...
The wireless local area network (WLAN) is becoming popular due to its inherent strength. However, there are major challenges to be over come in WLAN. Some of them are quality of service (QoS), seamless mobility and security. Extensive research is being carried out to address QoS in WLAN. In this paper we propose a new medium access control (MAC) protocol for QoS (New-MACQoS) in WLAN. It has been observed...
The IEEE 802.16 standard for broadband wireless metropolitan area network supports real time and non-real time services. It has a provision to design new packet-scheduling algorithms according to requirements to support quality of service (QoS) for real-time services. Till now published literature on WiMax states that, a service station (SS) requests for bandwidth to a base station (BS) for already...
IEEE 802.16 standard supports real time and non-real time services at each node. However, it has flexibility to develop customized scheduling algorithms according to different priority-based traffic's quality of service (QoS) requirements. Hence, it is imperative to obtain optimum scheduling schemes for different kinds of traffic (i.e., services). Earliest due date (EDD) is one of the highly referred...
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