Technology Cluster

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Al-Quds University’s Legal Services in Jerusalem 
(Ma’an Arab University Alliance for Civic Engagement, 2017-09-14) Ishaq, Isam; Nuseibah, Munir; Dajani, Rawan
Winner of “The most civically engaged campus” prize at Ma’an Second Annual Regional Competition. The AQU Community Action Centre (CAC) is located in the heart of Jerusalem’s Old City. The CAC works within its community, serving multi-dimensional needs focused on human rights and equality. Providing legal, social, educational, and gender-based services to the disadvantaged, the CAC supports citizens in claiming their rights from an often discriminatory Israeli government. CAC has provided services to Jerusalem communities, mainly in the Old City, through individual, Community Advocacy, and Legal clinics developed on a Rights-Based social work model. Other services are provided via Community and Civic Education, Women’s Empowerment, and Volunteer Units. Direct intervention services are provided holistically through the venues below.
Building embedded applications via REST services for the Internet of Things
(Association for Computing Machinery, 2013-11-11) Van den Abeele, Floris; Hoebeke, Jeroen; Ishaq, Isam; Teklemariam, Girum K; Rossey, Jen; Moerman, Ingrid; Demeester, Piet
As embedded networks are evolving to open systems, it’s be- coming possible to create new applications on top of these existing embedded systems. However, developing new appli- cations can be difficult due to the large diversity of protocols that exist today. In this paper, the authors demonstrate how employing the CoAP protocol can enable rapid application development by re-using well-known principles from the Web development world. Furthermore, we also demonstrate how a number of extensions to CoAP help to lower the barrier for developing applications even further.
Cloud-based Internet of Things Approach for SmartIrrigation System: Design and Implementation
(IEEE, 2020-12-17) Thaher, Thaer; Ishaq, Isam
Water plays a significant role in the economic de-velopment of countries. The agriculture sector is the most water-consuming; this sector consumes 69% of the freshwater. However,farmers often use traditional irrigation systems to water theircrops. These systems are ineffective and consume a lot of timeand effort, especially when there are several fields distributedin different geographical regions. Therefore, employing smartirrigation techniques will significantly overcome these problems.In this paper, we propose an intelligent irrigation frameworkbased on Wireless Sensor Network (WSN) and Internet of Things(IoT) cloud services. The proposed system consists of three maincomponents; the WSN, the control unit, and cloud services.Arduino Uno and XBee ZigBee modules are combined to gathersensors data and send them wirelessly to the control unit. YL-69 sensor is used to monitor the soil moisture. Raspberry Pi isutilized to gather data, process them, provide the proper decision,and transfer them to ThingSpeak IoT cloud. In the cloud, the datacollected from the system is stored to create instance visualizationof live data and send alerts. This allows farmers to monitor thestatus of crops and make the required decisions. After inspectingthe prototype, many challenges are posed for future work.
Contributions of mean and shape of bloodpressure distribution to worldwide trends andvariations in raised blood pressure: a pooledanalysis of 1018 population-based measurementstudies with 88.6 million participants
(Oxford University Press., 2018-03-19) Abdeen, Ziad A; NCD Risk Factor Collaboration (NCD-RisC)
Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20–29 years to 70–79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005–16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups.
Data Integrity Mechanism Using Hashing Verification
(2014-09-20) Hamamreh, Rushdi A.; Jamoos, Mohammed A.
In this paper, we propose a new One-Way Hash Algorithm, which is also obtains better efficiency and security, compared with a particular conventional hash algorithm, Hash algorithm can be used to determine if two values are equal, a hash function maps keys to small values[1]. DILH algorithm using linear combination of matrices to find non-invertible matrix, that takes advantage about of the compact representation of a set of numbers in a matrix, and fast calculations.
Discovery and Group Communication for Constrained Internet of Things Devices using the Constrained Application Protocol
(Ghent University, 2015) Ishaq, Isam
The ubiquitous Internet is rapidly spreading to new domains. This expansion of the Internet is comparable in scale to the spread of the Internet in the ’90s. The resulting Internet is now commonly referred to as the Internet of Things (IoT) and is expected to connect about 50 billion devices by the year 2020. This means that in just five years from the time of writing this PhD the number of interconnected devices will exceed the number of humans by sevenfold. It is further expected that the majority of these IoT devices will be resource constrained embedded devices such as sensors and actuators. Sensors collect information about the physical world and inject this information into the virtual world. Next processing and reasoning can occur and decisions can be taken to enact upon the physical world by injecting feedback to actuators. The integration of embedded devices into the Internet introduces new challenges, since many of the existing Internet technologies and protocols were not designed for this class of constrained devices. These devices are typically optimized for low cost and power consumption and thus have very limited power, memory, and processing resources and have long sleep periods. The networks formed by these embedded devices are also constrained and have different characteristics than those typical in todays Internet. These constrained networks have high packet loss, low throughput, frequent topology changes and small useful payload sizes. They are referred to as LLN. Therefore, it is in most cases unfeasible to run standard Internet protocols on this class of constrained devices and/or LLNs. New or adapted protocols that take into consideration the capabilities of the constrained devices and the characteristics of LLNs, are required. In the past few years, there were many efforts to enable the extension of the Internet technologies to constrained devices. Initially, most of these efforts were focusing on the networking layer. However, the expansion of the Internet in the 90s was not due to introducing new or better networking protocols. It was a result of introducing the World Wide Web (WWW), which made it easy to integrate services and applications. One of the essential technologies underpinning the WWW was the Hypertext Transfer Protocol (HTTP). Today, HTTP has become a key protocol in the realization of scalable web services building around the Representational State Transfer (REST) paradigm. The REST architectural style enables the realization of scalable and well-performing services using uniform and simple interfaces. The availability of an embedded counterpart of HTTP and the REST architecture could boost the uptake of the IoT. Therefore, more recently, work started to allow the integration of constrained devices in the Internet at the service level. The Internet Engineering Task Force (IETF) Constrained RESTful Environments (CoRE) working group has realized the REST architecture in a suitable form for the most constrained nodes and networks. To that end the Constrained Application Protocol (CoAP) was introduced, a specialized RESTful web transfer protocol for use with constrained networks and nodes. CoAP realizes a subset of the REST mechanisms offered by HTTP, but is optimized for Machine-to-Machine (M2M) applications. This PhD research builds upon CoAP to enable a better integration of constrained devices in the IoT and examines proposed CoAP solutions theoretically and experimentally proposing alternatives when appropriate. The first part of this PhD proposes a mechanism that facilitates the deployment of sensor networks and enables the discovery, end-to-end connectivity and service usage of newly deployed sensor nodes. The proposed approach makes use of CoAP and combines it with Domain Name System (DNS) in order to enable the use of userfriendly Fully Qualified Domain Names (FQDNs) for addressing sensor nodes. It includes the automatic discovery of sensors and sensor gateways and the translation of HTTP to CoAP, thus making the sensor resources globally discoverable and accessible from any Internet-connected client using either IPv6 addresses or DNS names both via HTTP or CoAP. As such, the proposed approach provides a feasible and flexible solution to achieve hierarchical self-organization with a minimum of pre-configuration. By doing so we minimize costly human interventions and eliminate the need for introducing new protocols dedicated for the discovery and organization of resources. This reduces both cost and the implementation footprint on the constrained devices. The second, larger, part of this PhD focuses on using CoAP to realize communication with groups of resources. In many IoT application domains, sensors or actuators need to be addressed as groups rather than individually, since individual resources might not be sufficient or useful. A simple example is that all lights in a room should go on or off as a result of the user toggling the light switch. As not all IoT applications may need group communication, the CoRE working group did not include it in the base CoAP specification. This way the base protocol is kept as efficient and as simple as possible so it would run on even the most constrained devices. Group communication and other features that might not be needed by all devices are standardized in a set of optional separate extensions. We first examined the proposed CoAP extension for group communication, which utilizes Internet Protocol version 6 (IPv6) multicasts. We highlight its strengths and weaknesses and propose our own complementary solution that uses unicast to realize group communication. Our solution offers capabilities beyond simple group communication. For example, we provide a validation mechanism that performs several checks on the group members, to make sure that combining them together is possible. We also allow the client to request that results of the individual members are processed before they are sent to the client. For example, the client can request to obtain only the maximum value of all individual members. Another important optional extension to CoAP allows clients to continuously observe resources by registering their interest in receiving notifications from CoAP servers once there are changes to the values of the observed resources. By using this publish/subscribe mechanism the client does not need to continuously poll the resource to find out whether it has changed its value. This typically leads to more efficient communication patterns that preserve valuable device and LLN resources. Unfortunately CoAP observe does not work together with the CoAP group communication extension, since the observe extension assumes unicast communication while the group communication extension only support multicast communication. In this PhD we propose to extend our own group communication solution to offer group observation capabilities. By combining group observation with group processing features, it becomes possible to notify the client only about certain changes to the observed group (e.g., the maximum value of all group members has changed). Acknowledging that the use of multicast as well as unicast has strengths and weaknesses we propose to extend our unicast based solution with certain multicast features. By doing so we try to combine the strengths of both approaches to obtain a better overall group communication that is flexible and that can be tailored according to the use case needs. Together, the proposed mechanisms represent a powerful and comprehensive solution to the challenging problem of group communication with constrained devices. We have evaluated the solutions proposed in this PhD extensively and in a variety of forms. Where possible, we have derived theoretical models and have conducted numerous simulations to validate them. We have also experimentally evaluated those solutions and compared them with other proposed solutions using a small demo box and later on two large scale wireless sensor testbeds and under different test conditions. The first testbed is located in a large, shielded room, which allows testing under controlled environments. The second testbed is located inside an operational office building and thus allows testing under normal operation conditions. Those tests revealed performance issues and some other problems. We have provided some solutions and suggestions for tackling those problems. Apart from the main contributions, two other relevant outcomes of this PhD are described in the appendices. In the first appendix we review the most important IETF standardization efforts related to the IoT and show that with the introduction of CoAP a complete set of standard protocols has become available to cover the complete networking stack and thus making the step from the IoT into the Web of Things (WoT). Using only standard protocols makes it possible to integrate devices from various vendors into one bigWoT accessible to humans and machines alike. In the second appendix, we provide an alternative solution for grouping constrained devices by using virtualization techniques. Our approach focuses on the objects, both resource-constrained and non-constrained, that need to cooperate by integrating them into a secured virtual network, named an Internet of Things Virtual Network or IoT-VN. Inside this IoT-VN full end-to-end communication can take place through the use of protocols that take the limitations of the most resource-constrained devices into account. We describe how this concept maps to several generic use cases and, as such, can constitute a valid alternative approach for supporting selected applications.
Dynamic User-Oriented Role Based Access Control Model (DUO-RBAC)
(EDA, 2018-10) Kiwan, Hazem; Jayousi, Rashid
Most researchers use role mining to generate role-based access con- trol model from the existing user-permission assignments. User-oriented role- based access control model is a type of role-based access control model, which aims to use role mining from an end-user perspective to generate an RBAC model. This research is the first for generating a dynamic user-oriented role- based access control model for inserting a new user-permission assignments to the existing model re-generating roles, with a constraint that there are no changes in the number of role assignments for each user in the system after the insertion process, since the user will be conflicted if he has different number of roles from time to time. Also, we have developed a new algorithm, which based on user-oriented role mining to find the way to insert the new U P A to the existing model. Our experiments applied on benchmark "Access Control" real datasets to evaluate the results.
Electromagnetic interactions analysis between tow 3-D scatteres using the e-pilemethod combined with the po approximation
(2014-01-29) Kouali, Mohammad; Kubicke, Gildas; Bourlier, Christophe
In this paper, the electromagnetic scattering from two scatterers is analyzed from a rigorous integral formulation solved by the method of moments (MoM). G. Kubick¶e has recently developed the E- PILE (Extended Propagation-Inside-Layer Expansion) method to calculate the scattering from an object above a rough surface for a two-dimensional problem. This method allows us to calculate separately and exactly the interactions between the object and the rough surface. The purpose of this paper is to extend the E-PILE method to a three-dimensional problem. Such a 3-D problem involves a large number of unknowns and can not be solved easily with a conventional method of moments by using a direct LU inversion. Thus to solve this issue, the E-PILE method is combined with the physical optics (PO) approximation to calculate the local interactions on both the object and the rough surface. By using this hybrid method, the requirements of memory and CPU time can be reduced signi¯cantly.
Experimental Evaluation of Unicast and Multicast CoAP Group Communication
(Multidisciplinary Digital Publishing Institute, 2016-07-21) Ishaq, Isam
The Internet of Things (IoT) is expanding rapidly to new domains in which embedded devices play a key role and gradually outnumber traditionally-connected devices. These devices are often constrained in their resources and are thus unable to run standard Internet protocols. The Constrained Application Protocol (CoAP) is a new alternative standard protocol that implements the same principals as the Hypertext Transfer Protocol (HTTP), but is tailored towards constrained devices. In many IoT application domains, devices need to be addressed in groups in addition to being addressable individually. Two main approaches are currently being proposed in the IoT community for CoAP-based group communication. The main difference between the two approaches lies in the underlying communication type: multicast versus unicast. In this article, we experimentally evaluate those two approaches using two wireless sensor testbeds and under different test conditions. We highlight the pros and cons of each of them and propose combining these approaches in a hybrid solution to better suit certain use case requirements. Additionally, we provide a solution for multicast-based group membership management using CoAP.
Experimental Evaluation of Unicast and Multicast CoAP Group Communication
(MDPI, 2016-07-21) Ishaq, Isam
The Internet of Things (IoT) is expanding rapidly to new domains in which embedded devices play a key role and gradually outnumber traditionally-connected devices. These devices are often constrained in their resources and are thus unable to run standard Internet protocols. The Constrained Application Protocol (CoAP) is a new alternative standard protocol that implements the same principals as the Hypertext Transfer Protocol (HTTP), but is tailored towards constrained devices. In many IoT application domains, devices need to be addressed in groups in addition to being addressable individually. Two main approaches are currently being proposed in the IoT community for CoAP-based group communication. The main difference between the two approaches lies in the underlying communication type: multicast versus unicast. In this article, we experimentally evaluate those two approaches using two wireless sensor testbeds and under different test conditions. We highlight the pros and cons of each of them and propose combining these approaches in a hybrid solution to better suit certain use case requirements. Additionally, we provide a solution for multicast-based group membership management using CoAP.
Flexible Unicast-Based Group Communication for CoAP-Enabled Devices
(Sensors, 2014-06-04) Ishaq, Isam
Smart embedded objects will become an important part of what is called the Internet of Things. Applications often require concurrent interactions with several of these objects and their resources. Existing solutions have several limitations in terms of reliability, flexibility and manageability of such groups of objects. To overcome these limitations we propose an intermediately level of intelligence to easily manipulate a group of resources across multiple smart objects, building upon the Constrained Application Protocol (CoAP). We describe the design of our solution to create and manipulate a group of CoAP resources using a single client request. Furthermore we introduce the concept of profiles for the created groups. The use of profiles allows the client to specify in more detail how the group should behave. We have implemented our solution and demonstrate that it covers the complete group life-cycle, i.e., creation, validation, flexible usage and deletion. Finally, we quantitatively analyze the performance of our solution and compare it against multicast-based CoAP group communication. The results show that our solution improves reliability and flexibility with a trade-off in increased communication overhead.
Flexible unicast-based group communication for coap-enabled devices
(Multidisciplinary Digital Publishing Institute, 2014-06-04) Ishaq, Isam
Smart embedded objects will become an important part of what is called the Internet of Things. Applications often require concurrent interactions with several of these objects and their resources. Existing solutions have several limitations in terms of reliability, flexibility and manageability of such groups of objects. To overcome these limitations we propose an intermediately level of intelligence to easily manipulate a group of resources across multiple smart objects, building upon the Constrained Application Protocol (CoAP). We describe the design of our solution to create and manipulate a group of CoAP resources using a single client request. Furthermore we introduce the concept of profiles for the created groups. The use of profiles allows the client to specify in more detail how the group should behave. We have implemented our solution and demonstrate that it covers the complete group life-cycle, ie., creation, validation, flexible usage and deletion. Finally, we quantitatively analyze the performance of our solution and compare it against multicast-based CoAP group communication. The results show that our solution improves reliability and flexibility with a trade-off in increased communication overhead.
Group Communication in Constrained Environments using CoAP-based Entities
(Institute of Electrical and Electronics Engineers, 2013-05-20) Ishaq, Isam
The Constrained Application Protocol (CoAP) is a new Internet protocol that is currently being standardized. CoAP allows access to the drastically increasing number of smart objects and their sensing resources from virtually anywhere. It is a light-weight protocol designed to cope with the restrictions imposed by the limited resources (CPU, memory, power,…) of many smart objects. Depending on the application, information from individual objects might not be sufficient, reliable, or useful. An application may need to aggregate and/or compare data from a group of objects in order to obtain accurate results. Although multicast may be used to transmit the same request to several objects, multicast communication with smart objects has some disadvantages. Programming individual requests is another solution but lacks flexibility and opportunities for reusability. In this paper we propose a novel CoAP-based approach for communication with a group of resources across multiple smart objects. This approach organizes the group of resources that should be accessed into a new CoAP resource, called an entity, and nicely integrates several important aspects of entity management: creation, validation, usage and manipulation. In order to demonstrate the feasibility of this approach we present an implementation and experimental validation.
IETF Standardization in the Field of the Internet of Things (IoT): A Survey
(MDPI AG, 2013-04-25) Ishaq, Isam; Carels, David; Teklemariam, Girum; Abeele, Floris; De Poorter, Eli
Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there have been many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. In this paper, we will briefly review the history of integrating constrained devices into the Internet, followed by an extensive overview of IETF standardization work in the 6LoWPAN, ROLL and CoRE working groups. This is complemented with a broad overview of related research results that illustrate how this work can be extended or used to tackle other problems and with a discussion on open issues and challenges. As such the aim of this paper is twofold: apart from giving readers solid insights in IETF standardization work on the Internet of Things, it also aims to encourage readers to further explore the world of Internet-connected objects, pointing to future research opportunities.
Improving Irrigation by Using a Cloud Based IoT System
(IEEE, 2020-12-17) Assaf, Rasha; Ishaq, Isam
Palestine is a fertile country, and the agriculture system is a significant part of its economy. In Palestine, farming depends on rainfall, however, the rainfall amount has been decreasing over the years and springs are drying out. Therefore, the irrigation system is considered one of the most used systems in the agriculture field. However, there are many factors that should be taken into consideration to control the right amount of water that should be provided to the plant when using the irrigation system, like the soil type, the fertility of the soil, the moisture level, humidity, and temperature of the soil. Our proposed irrigation system takes into account those factors to automate the amount of water dispensed to the plants. The project employs a microcontroller module (ESP8266) which connects the system to the internet by WiFi. This module controls two relays for supplying water to the field, and triggers the fans based on the information obtained from the soil moisture and temperature humidity sensor. This entire system is monitored and controlled by a Blynk server.
Observing CoAP groups efficiently
(Elsevier, 2016-02-29) Ishaq, Isam
It is envisioned that by the year 2020 the Internet will contain more than 50 billion devices, among which the majority of them will have constraints in terms of memory, processing power or energy. As a consequence, they are often unable to run current standard Internet protocols, requiring special, optimized protocols. A number of these protocols, covering the different layers of the protocol stack, have been developed and standardized lately. At the application level, the Constrained Application Protocol (CoAP) is proposed by the IETF as an HTTP replacement that is suitable for constrained devices. CoAP is a very light-weight base protocol that can be extended with optional specifications to satisfy specific use case needs. Two important optional specifications are observe, allowing monitoring of a CoAP resource over a period of time, and group communication, supporting interactions with multiple CoAP devices at once. Currently, these two optional specifications do not work together, i.e., it is not possible to gain the benefits of both of them at the same time. In this paper we present an alternative and novel approach to CoAP group communication that works well with the CoAP observe extension. In addition, it enables to perform operations on the observed results, bringing intelligence closer to the data sources.
Online Monitoring Health Station Using Arduino Mobile Connected to Cloud service “Heart Monitor” System
(IEEE, 2020-12-16) Karajah, Eman; Ishaq, Isam
This paper presents a monitoring health station system for vital signs called “Heart monitor”. Heart Monitor is a system which can measure the heart rates and body temperatures of patients and then record them in cloud services. The cloud services can then be accessed in real-time by the medical staff to monitor the patients’ health at any given location and time. This system is connected to a mobile phone which sends an alarm if the heart rate values become abnormal. After 5 abnormal readings it will automatically call the doctor or the person whose number is included in the system. The system is tested and compered to an ECG device. The results show an excellent accuracy of 97.4%.
Performance Evaluation of Palestinian Mobile Networks Based on Crowdsourcing Measurements
(IEEE International Conference on Electrical and Electronics Engineering (ICEEE), Marmaris, Turkiye, 2024-04-22) Safa Nassereldin, Rami Sawalmeh, Mohammad Barakat, Nadeen Shanan, and Ali Jamoos
The evaluation of mobile network performance involves assessing various key performance indicators (KPIs) that gauge the efficiency and effectiveness of these networks. The key performance indicators of the Palestinian mobile networks are usually monitored by the mobile network operators (MNOs) through their operation support subsystems and the carried-out drive tests. This include the received signal level, received signal quality, drop rate, handover success rate, packet loss, latency, throughput, etc. The Palestinian ministry of telecommunications and information technology (MTIT) together with the Palestinian Telecom Regulatory Authority (PTRA) also conduct performance measurements for the mobile networks through drive tests to monitor the quality of service (QoS) measurements delivered by each mobile operator and compare them with the standard KPIs benchmark limits. They aim to enhance user experience and network efficiency. However, these performance measurements either from the MNOs or the regulation agency are limited and do not reflect the exact end user experience. Therefore, in this paper, we address the performance evaluation of the Palestinian MNOs based on a large community of connected people smartphone crowdsourcing technique. Here, using smartphone crowdsourcing can collect continuous real-time data on network performance from a large number of smartphone users with various locations. Thus, the quality of experience (QoE) can be evaluated from the end user perspective with a bigger data set. In this paper, we have developed and implemented a smartphone application called “Signal Sense” for crowdsourced mobile network measurements. The performed measurements include location information, signal level, signal quality and throughput for 3G mobile networks in Palestine. The evaluation of these measurements reflects the relative performance of the Palestinian MNOs.
Propagation Model Tuning for Terrestrial Microwave Links in Palestine
(IEEE, 2022-07-26) Ali Jamoos
In this paper, we have studied the terrestrial microwave links operated by the Palestinian mobile network operator (JAWWAL). Particularly, we have analyzed the path loss power measurements from 90 active terrestrial microwave links at three different frequencies which are 15GHz, 18GHz and 23GHz covering all geographical locations in the West Bank. The length of these microwave links varies from about 0.174Km to 33.864Km. The path loss power measurements were compared with that of the theoretical free-space propagation model as well as with the results obtained from Mentum Ellipse software simulation tool. The root mean square error results show that the free-space model is far away (7.64 dB) from the measured data. Therefore, we have suggested to tune the free-space propagation model based on linear least squares method. The proposed tuned free-space model yields better fit to the measured data with reduced root mean square error of 5.84 dB. In addition, the suggested tuned model yields comparable results to that obtain by Mentum Ellipse simulation.
Securing End-to-End Wireless Mesh Networks Ticket-Based Authentication
(2011-02-02) Hamamreh, Rushdi A.; Melhem, Anas M.
Hybrid wireless mesh network (WMN) consists of two types of nodes: Mesh Routers which are relatively static and energy-rich devices, and Mesh Clients which are relatively dynamic and power constrained devices. In this paper we present a new model for WMN end-to-end security which divide authentication process into two phases: Mesh Access Point phase which based on asymmetric cryptography and Mesh Client phase which based on a server-side certificate such as EAP-TTLS and PEAP.