414 research outputs found
Macro/micro-mobility fast handover in hierarchical mobile IPv6
Mobile Internet Protocol version 6 (MIPv6) has been proposed to solve the problem of mobility in the new era of Internet by handling
routing of IPv6 packets to mobile nodes that have moved away from their home network. Users will move frequently between networks, as
they stay connected to the Internet. Thus, as mobility increases across networks, handovers will significantly impact the quality of the
connection and user application.
However, MIPv6 only defines means of managing global (macro)-mobility but does not address micro-mobility separately. Instead, it uses
the same mechanism in both cases. This involves long handover delay and signaling load. The Hierarchical Mobile IPv6 (HMIPv6) protocol
has been proposed as an extension of basic MIPv6 to solve this problem by splitting the handover management into macro-mobility and
micro-mobility schemes. HMIPv6 introduced a new protocol agent called Mobility Anchor Point (MAP) to manage mobility and serve as a
local entity to aid in mobile handover. The handover (or registration) operation is the operation when MN registers its presence to its Home
Agent (HA) and Correspondent Node (CN).
This paper proposes a mechanism to perform fast handover in HMIPv6 by adopting the multicast technique to the MAP for both macromobility
and micro-mobility management. Our proposal is designed to minimize service disruption that occurs during the registration
operation. We simulate the performance using network simulator (NS-2) and we present and analyze the performance testing for our proposal
by comparing it with the basic hierarchical mobile IPv6. The results show that our scheme allows the MN to receive packets faster than the
basic HMIPv6
Macro/micro-mobility fast handover in hierarchical mobile IPv6
Mobile Internet Protocol version 6 (MIPv6) has been proposed to solve the problem of mobility in the new era of Internet by handling routing of IPv6 packets to mobile nodes that have moved away from their home network. Users will move frequently between networks, as they stay connected to the Internet. Thus, as mobility increases across networks, handovers will significantly impact the quality of the connection and user application.
However, MIPv6 only defines means of managing global (macro)-mobility but does not address micro-mobility separately. Instead, it uses the same mechanism in both cases. This involves long handover delay and signaling load. The Hierarchical Mobile IPv6 (HMIPv6) protocol has been proposed as an extension of basic MIPv6 to solve this problem by splitting the handover management into macro-mobility and micro-mobility schemes. HMIPv6 introduced a new protocol agent called Mobility Anchor Point (MAP) to manage mobility and serve as a local entity to aid in mobile handover. The handover (or registration) operation is the operation when MN registers its presence to its Home Agent (HA) and Correspondent Node (CN).
This paper proposes a mechanism to perform fast handover in HMIPv6 by adopting the multicast technique to the MAP for both macro-mobility and micro-mobility management. Our proposal is designed to minimize service disruption that occurs during the registration operation. We simulate the performance using network simulator (NS-2) and we present and analyze the performance testing for our proposal by comparing it with the basic hierarchical mobile IPv6. The results show that our scheme allows the MN to receive packets faster than the basic HMIPv6
Advanced Multiple Access Schemes for Multimedia Traffic over Wireless Channels
To meet the anticipated demand for wireless access to the broadband Asynchronous Transfer Mode (ATM) network, the concept of wireless ATM has been proposed in 1994 [1]. One of the main challenges in the design of a wireless ATM network resides in the conception of a Medium Access Control
(MAC) protocol that will handle the different ATM services while providing an efficient utilization of the wireless channel. In this thesis, we propose a new Adaptive Reservation TDMA (AR-TDMA) MAC protocol for wireless ATM
networks. AR-TDMA combines the advantage of distributed access and centralized control for transporting Constant Bit Rate (CBR), Variable Bit Rate (VBR) and Available Bit Rate (ABR) traffic efficiently over a wireless channel. The contention slots's access is governed by two novel framed
pseudo-Bayesian priority Aloha protocols that we introduce in this thesis. Either one of these protocols can minimize the contention delay and provide different access priorities for heterogeneous traffic. Analytical and simulation results indicate that the framed pseudo-Bayesian priority Aloha protocols offer a significant delay improvement for high priority packets with Poisson traffic, while low priority packets only experience a slight
performance degradation. A detailed comparison and discussion of implementation and robustness issues is presented in this thesis to help the design engineer choose the right protocol that suits the application scenario.
In the context of the AR-TDMA protocol, results show that the priority algorithms improve real-time traffic Quality-of-Service (QoS). The AR-TDMA resource allocation algorithm grants to terminals reserved access to the wireless ATM channel by considering their requested bandwidth and QoS.
We propose scheduling algorithms for CBR, VBR and ABR traffic. Furthermore, we also introduce a method to dynamically adjust the number of uplink control slots per frame as a function of the estimated contention traffic. Finally, an algorithm is proposed to integrate these algorithms to provide ubiquitous wireless ATM services. Performance results show that the AR-TDMA MAC protocol can achieve high throughput in the range of 90 to 95% while maintaining reasonable QoS for all ATM services
The FPBA algorithm with controlled capture ICC2001
Abstract-In this paper, we introduce a new mixed priority
scheme that utilizes the LESRTPL model [S] to control the
assignment of the transmitter power levels, assigned to each
priority class, whose contending over the wireless channel using
the FPBA algorithm [l] to capture the channel. The wireless
channel capture model includes Rayleigh fading, shadowing, and
path loss. The performance of the algorithm is evaluated using
simulation models. Results show that the new priority scheme
offers significant improvement to the throughput and the waiting
time of the different priority classes, especially to high priority
class packets
Transmission power consumption management for zigbee healthnets
In clinical diagnostics and patient's treatment, many physiological parameters, referred to as emergency vital signs or EVS such as blood gas, invasive blood pressures, pulse rate, temperature, electrocardiogram (ECG), etc, have to be detected, measured and monitored. Wireless ZigBee networks utilize digital data to enable such novel clinical applications. With the use of small portable computers at other locations within the hospital or elderly nursing
home, medical staff would be able to monitor a patient regardless of her position as long as she is connected to the network. Sometimes battery operated sensors are embedded into the patient's body, hence replacing the sensor's battery is done by a surgical operation. In such
scenarios, it is important to prolong the battery's life as much as possible. In This paper, a simple yet effective method that can be used to reduce power consumption of wireless sensor nodes is presented. Power consumption is measured while doing data transmission, reception
or in idle state. Depending on the estimated distance calculated from the averaged received signal strength Indicator (RSSI), the transmission power needed were computed and used for each packet transmission. Hence, instead of transmitting in full pmver regardless of the
location of the receiving node, the transmission power is carefully controlled depending on the estimated distance
Adaptive reservation TDMA protocol for wireless multimedia traffic
An Adaptive Reservation Time Division Multiple Access (AR-TDMA) control protocol for Wireless Asynchronous
Transfer Mode (WATM) networks is proposed in this paper. AR-TDMA combines the advantages of distributed
access and centralised control for transporting Constant Bit Rate (CBR), Variable Bit Rate (VBR) and Available Bit
Rate (ABR) traffic efficiently over a wireless channel. The contention slots access for reservation requests is
governed by two protocols, the Adaptive Framed Pseudo-Bayesian Aloha with Adaptive Slot Assignment (AFPBAASA)
protocol and the Framed Pseudo-Bayesian Aloha with Adaptively Prioritised Controlled Capture (FPBAAPCC)
protocol. Both protocols provide different access priorities to the control packets in order to improve the
Quality-of-Service (QoS) offered to time sensitive connections. AR-TDMA also features a novel integrated resource
allocation algorithm that efficiently schedules terminals’ reserved access to the wireless ATM channel by
considering their requested bandwidth and QoS. Integration of CBR, voice, VBR, data and control traffic over the
wireless ATM channel using the proposed AR-TDMA protocol is considered in the paper. The performance of the
AR-TDMA in conjunction with the AFPBA-ASA protocol and FPBA-APCC protocol has been investigated and the
simulation results are presented showing that the protocol satisfies the required QoS of each traffic category while
providing a highly efficient utilisation of approximately 96% for the wireless ATM channel
Adaptive framed pseudo-Bayesian Aloha algorithm with priorities
A new wireless framed pseudo-bayesian Aloha algorithm with adaptive priorities, for wireless ATM reservation-based TDMA
MAC prolocols, is presented. The throughput in the presence of Rayleigh-fading, shadowing and capture is calculated, and the waiting time of the different priority classes is estimated using simulated models
A new congestion control algorithm for active networks
This paper discusses and analyses different congestion control schemes for active networks and proposes a new one. The proposed scheme strikes a balance between the number of errors considered and the waiting time before taking action. The scheme implemented works on "Choke packet" concept,
where the source is instructed to reduce the transmission rate. Reasonable reduction of transmission rate is maintained at the source as the intermediate nodes in active networks platform take actions instead of the usually acting
destination nodes. The proposed scheme was simulated using OPNET and simulation results are reported. Results indicate that the source-quenching technique implemented in the intermediate nodes of the active network reduces congestion drastically and improves overall network performance
Utilising signal measurement in bandwidth reservation scheme for QOS provisioning in multimedia wireless networks
Next generation multimedia wireless networks require guaranteed quality of service (QoS) over the duration of mobile connections, and also require efficient use of network resources. In this paper, bandwidth reservation scheme is proposed for QoS provisioning in multimedia wireless networks. The proposed scheme integrates user mobility information obtained by measuring Received Signal Strength (RSS) for determining the next cell the mobile user is likely to move to. Simulation results demonstrate that the proposed scheme can guarantee the required QoS requirements in terms of handoff call dropping probability and new call blocking probability while maintaining efficient use of network resources
Harvesting WiFi Received Signal Strength Indicator (RSSI) for control/automation system in SOHO indoor environment with ESP8266
WiFi are easily available almost
everywhere nowadays. Due to this, there is
increasing interest in harnessing this technology
for purposes other than communication.
Therefore, this research was carried out with the
main idea of using WiFi in developing an efficient,
low cost control system for small office home office
(SOHO) indoor environment. The main objective
of the research is to develop a proof of concept
that WiFi received signal strength indicator
(RSSI) can be harnessed and used to develop a
control system. The control system basically will
help to save energy in an intelligent manner with a
very minimum cost for the controller circuit.
There are two main parts in the development of
the system. First is extracting the RSSI monitoring
feed information and analyzing it for designing the
control system. The second is the development of
the controller circuit for real environment. The
simple yet inexpensive controller was tested in an
indoor environment and results showed successful
operation of the circuit developed
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