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mobile-telecommunication-systems
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Virtual address space mapping for IP auto-configuration in MANET with security capability
, Article Proceedings of the 2008 International Conference on Advanced Infocomm Technology, ICAIT '08, 29 July 2008 through 31 July 2008, Shenzhen ; 2008 ; 9781605580883 (ISBN) ; Tajamolian, M ; Dehghan, M ; Mousavi, R ; Sharif University of Technology
2008
Abstract
Mobile Ad Hoc Networks (MANETs) are networks with selforganizing capabilities and without a fixed infrastructure. Wireless nodes communicate among themselves using multi-hop radio relaying, without requiring the packets to pass through a central access point or a base station. In a highly mobile and infrastructure-less scenario, pre-configuration of addresses is not possible. Therefore node addresses need to be configured dynamically with minimum delay and packet loss. Existing solutions for IP address auto-configuration do not address security issues. In this paper we propose a secure address autoconfiguration for Mobile Ad hoc Networks (MANET) based on Virtual Address Space Mapping [1]....
Ultra-Dense 5G small cell deployment for fiber and wireless backhaul-aware infrastructures
, Article IEEE Transactions on Vehicular Technology ; 2018 ; 00189545 (ISSN) ; Beyranvand, H ; Salehi, J. A ; Maier, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
In this paper, we study the cell planning problem for a two-tier cellular network containing two types of base stations (BSs)— i.e. with fiber backhaul, referred to as wired BSs (W-BSs), and BSs with wireless backhaul, referred to as unwired-BSs (U-BSs). In-band full-duplex wireless communications is used to connect U-BSs and W-BSs. We propose an algorithm to determine the minimum number of W-BSs and U-BSs to satisfy given cell and capacity coverage constraints. Furthermore, we apply our proposed non-dominated sorting genetic algorithm II (NSGA-II) to solve the joint cell and backhaul planning problem to minimize the cost of planning, while maximizing the coverage simultaneously....
Tree optimization in overlay multicast based on location and bandwidth
, Article ICCTD 2009 - 2009 International Conference on Computer Technology and Development, 13 November 2009 through 15 November 2009 ; Volume 2 , 2009 , Pages 46-49 ; 9780769538921 (ISBN) ; Movaghar, A ; Sharif University of Technology
Abstract
One of the main parts of peer-to-peer multicast is the structure of overlay network. Most of the existing works utilize some common parameters for constructing overlay tree. These parameters are bandwidth and delay. The mismatch between current overlay structure and underlying network topology causes severe link stress and then leads to high end to end latency. According to these problems, we propose a new overlay construction algorithm called OLT in this paper that finds the location of peers and tries to connect peers that are as close as possible. OLT exploits a number of heuristic techniques to reach an optimized tree even in case of peer heterogeneity and high churn rate. Our...
Travel mode detection exploiting cellular network data
, Article MATEC Web of Conferences, 6 July 2016 through 10 July 2016 ; Volume 81 , 2016 ; 2261236X (ISSN) ; Shafahi, Y ; Sharif University of Technology
EDP Sciences
2016
Abstract
There has been growing interest in exploiting cellular network data for transportation planning purposes in recent years. In this paper, we utilize these data for determining mode of travel in the city of Shiraz, Iran. Cellular data records -including location updates in 5minute time intervals- of 300,000 users from the city of Shiraz has been collected for 40 hours in three consecutive days in a cooperation with the major telecommunications service provider of the country. Depending on the density of mobile BTS's in different zones of the city, the user location can be located within an average of 200 meters. Considering data filtering and smoothing, data preparation and converting them to...
Toward 5G: FiWi Enhanced LTE-A HetNets with Reliable Low-Latency Fiber Backhaul Sharing and WiFi Offloading
, Article IEEE/ACM Transactions on Networking ; Volume PP, Issue 99 , 2016 ; 10636692 (ISSN) ; Levesque, M ; Maier, M ; Salehi, J. A ; Verikoukis, C ; Tipper, D ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
To cope with the unprecedented growth of mobile data traffic, we investigate the performance gains obtained from unifying coverage-centric 4G mobile networks and capacity-centric fiber-wireless (FiWi) broadband access networks based on data-centric Ethernet technologies with resulting fiber backhaul sharing and WiFi offloading capabilities. Despite recent progress on backhaul-aware 4G studies with capacity-limited backhaul links, the performance-limiting impact of backhaul latency and reliability has not been examined in sufficient detail previously. In this paper, we evaluate the maximum aggregate throughput, offloading efficiency, and in particular, the delay performance of FiWi enhanced...
Toward 5G: Fiwi enhanced lte-a hetnets with reliable low-latency fiber backhaul sharing and wifi offloading
, Article IEEE/ACM Transactions on Networking ; Volume 25, Issue 2 , 2017 , Pages 690-707 ; 10636692 (ISSN) ; Levesque, M ; Maier, M ; Salehi, J. A ; Verikoukis, C ; Tipper, D ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
To cope with the unprecedented growth of mobile data traffic, we investigate the performance gains obtained from unifying coverage-centric 4G mobile networks and capacity-centric fiber-wireless (FiWi) broadband access networks based on data-centric Ethernet technologies with resulting fiber backhaul sharing and WiFi offloading capabilities. Despite recent progress on backhaul-aware 4G studies with capacity-limited backhaul links, the performance-limiting impact of backhaul latency and reliability has not been examined in sufficient detail previously. In this paper, we evaluate the maximum aggregate throughput, offloading efficiency, and in particular, the delay performance of FiWi enhanced...
Technique for order of preference by similarity to ideal solution based predictive handoff for heterogeneous networks
, Article IET Communications ; Volume 10, Issue 13 , 2016 , Pages 1682-1690 ; 17518628 (ISSN) ; Kalbkhani, H ; Lotfollahzadeh, T ; Shayesteh, M. G ; Solouk, V ; Sharif University of Technology
Institution of Engineering and Technology
Abstract
This study presents an efficient handoff algorithm for heterogeneous networks comprising macrocells, microcells, picocells, and femtocells. The proposed algorithm is based on call admission control (CAC) for selecting target base station (BS) from a list of neighbouring candidate BSs, as well as using the technique for order of preference by similarity to ideal solution (TOPSIS) as decision method. The introduced algorithm takes into account multiple criteria including measured received signal strength (RSS) and signal-to-interference-plus noise ratio (SINR), predicted RSS and SINR, and number of free resource blocks of neighbouring BSs. With the use of TOPSIS, neighbouring BSs are ordered...
Taking multiple-choise quiz by SMS on mobile phones including analyzing property
, Article Journal of Computers (Finland) ; Volume 2, Issue 2 , 2007 , Pages 53-60 ; 1796203X (ISSN) ; Sharif University of Technology
Academy Publisher
2007
Abstract
Recently Mobile Learning (M-Learning) has attracted much attention. Due to advantages of SMS (Short Messaging Service) on mobile phones we present a safe and protected method for taking multiple-choice quizzes by using the SMS on mobile phones in this paper. In this method questions of quiz are sent to students along with their answers through some SMS messages. The students will receive their grades immediately after answering the questions and this grade is also sent to the instructor or professor along with the student's answers through an SMS Picture Message. Answers of questions and the student's grade are hidden in SMS picture message through stenography and then they are sent. The...
Symmetric relaying strategy for two-relay networks
, Article IEEE Communications Letters ; Volume 12, Issue 10 , 2008 , Pages 708-710 ; 10897798 (ISSN) ; Aref, M. R ; Sharif University of Technology
2008
Abstract
In this paper, we propose a concept of relaying named symetric relaying strategy for two relay network. In our strategy, we have two relays in the network and both relays can completely decode the message transmitted by the other relay. The proposed rate is shown to subsume the previously proposed rate for feed-forward relay network based on decodeand- forward. © 2008 IEEE
Stealth steganography in SMS
, Article 2006 IFIP International Conference on Wireless and Optical Communications Networks, Bangalore, 11 April 2006 through 13 April 2006 ; 2006 ; 1424403405 (ISBN); 9781424403400 (ISBN) ; Sharif University of Technology
IEEE Computer Society
2006
Abstract
The short message service, abbreviated to SMS, is one of the services used in mobile phones and has been warmly welcomed by the public throughout the world, esp. in Asia and Europe. Using this service, individuals can write and send to each other short messages and also black and white pictures. On the one hand, considering the issue of information security and esp. establishing hidden communications, many methods have been presented for hidden communications, among which steganography is a relatively new one. Combining steganography of data in picture and using pictures in SMS messages, this article proposes a method for hidden exchange of information. The main focus of this article is on...
Standing phase angle reduction based on a wide area monitoring system using genetic algorithm
, Article International Journal of Emerging Electric Power Systems ; Volume 11, Issue 3 , Jul , 2010 ; 1553779X (ISSN) ; Ranjbar, A. M ; Pishvaie, M. R ; Sadeghi, M ; Sharif University of Technology
2010
Abstract
During power system restoration, it is necessary to check the phase angle between two buses before closing circuit breakers to connect a line between them. A novel approach for reducing large standing phase angle (SPA) based on Genetic Algorithm (GA) is presented in this paper. The proposed approach starts with a state estimation on Wide Area Monitoring System (WAMS) data measurements and considering power system operation and angular stability constraints, seeks an optimal control action scenario for reducing SPA. Since these constraints are evaluated based on WAMS data, the presented approach is considerably high speed and accurate. As an optimization problem, objective function of the...
Software watermarking by equation reordering
, Article 2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications, ICTTA, Damascus, 7 April 2008 through 11 April 2008 ; 2008 ; 1424417511 (ISBN); 9781424417513 (ISBN) ; Shirali Shahreza, S ; Sharif University of Technology
2008
Abstract
Watermarking is the process of hiding information in a media and usually used to for copyright protection. In software watermarking, the information is added to the source code of program and can be extracted from compiled executable code. In this paper, a new software watermarking algorithm is proposed by equation reordering. In this method, the order of operands in an equation is changed according to the information we want to hide in a way that the result of the equation is unchanged. One of the main advantages of this method is that no code added to the program, so the size and speed of the program not changed
Secrecy throughput maximization for full-duplex wireless powered IOT networks under fairness constraints
, Article IEEE Internet of Things Journal ; Volume 6, Issue 4 , 2019 , Pages 6964-6976 ; 23274662 (ISSN) ; Sun, S ; Kang, X ; Guan, Y. L ; Pakravan, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, we study the secrecy throughput of a full-duplex wireless powered communication network (WPCN) for Internet of Things (IoT). The WPCN consists of a full-duplex multiantenna base station (BS) and a number of sensor nodes. The BS transmits energy all the time, and each node harvests energy prior to its transmission time slot. The nodes sequentially transmit their confidential information to the BS, and the other nodes are considered as potential eavesdroppers. We first aim to optimize the sum secrecy throughput of the nodes. The optimization variables are the duration of the time slots and the BS beamforming vectors in different time slots. The optimization problem is shown to...
SEAODV: Secure efficient AODV routing protocol for MANETs networks
, Article ACM International Conference Proceeding Series, 24 November 2009 through 26 November 2009, Seoul ; Volume 403 , 2009 , Pages 940-944 ; 9781605587103 (ISBN) ; Movaghar, A ; Safi, S. M ; Sharif University of Technology
Abstract
Secure routing is one of the most important topics in the wireless MANETs networks. MANETs networks don't have a central infrastructure for the management of routing in the networks. Each node independently routes and sends packets, so many attacks such as forging, modifying, and denial of service (DoS), Occur in these networks. In this paper, we present the new protocol, SEAODV; Secure Efficient Ad-hoc on Demand Routing Protocol for MANETs networks. SEAODV is based on the AODV algorithm and in comparison with existing secure AODV protocols such as SAODV, ARAN and SEAR have improved security and performances. SEAODV uses HEAP authentication Scheme with symmetric cryptography and one-way hash...
Role of cooling rate in selective synthesis of graphene and carbon nanotube on Fe foil using hot filament chemical vapor deposition
, Article 2016 IEEE 7th Annual Ubiquitous Computing, Electronics and Mobile Communication Conference, UEMCON 2016, 20 October 2016 through 22 October 2016 ; 2016 ; 9781509014965 (ISBN) ; Kaminska, B ; Akhavan, O ; Talebi, S ; Ghoranneviss, M ; Arab, Z ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
In this study, graphene sheets and carbon nanotubes (CNTs) were selectively grown on Fe foil at a relatively low growth temperature and varying cooling rates using a hot filament chemical vapor deposition (HFCVD) apparatus with C2H2 as the precursor. The results of the scanning electron microscopy and Raman spectroscopy revealed that the increase of the cooling rate from 7 to 10 or 20 °C/min provoked a structure transition from CNT to graphene. The optimum crystal quality of the graphene sheets (Iq/Id ∼1.1) was achieved at the cooling rate of 20 °C/min. According to the AFM analysis, the thickness of the stacked graphene sheets was found to be ∼2.9-3.8 nm containing ∼8-11 monolayers. The XRD...
Robust parameter design using the weighted metric method-the case of 'the smaller the better'
, Article International Journal of Applied Mathematics and Computer Science ; Volume 19, Issue 1 , 2009 , Pages 59-68 ; 1641876X (ISSN) ; Noorossana, R ; Akhavan Niaki, T ; Lahijanian, H ; Sharif University of Technology
2009
Abstract
In process robustness studies, it is desirable to minimize the influence of noise factors on the system and simultaneously determine the levels of controllable factors optimizing the overall response or outcome. In the cases when a random effects model is applicable and a fixed effects model is assumed instead, an increase in the variance of the coefficient vector should be expected. In this paper, the impacts of this assumption on the results of the experiment in the context of robust parameter design are investigated. Furthermore, two criteria are considered to determine the optimum settings for the control factors. In order to better understand the proposed method and to evaluate its...
Resource allocation in integrated femto-macrocell networks based on location awareness
, Article IET Communications ; Volume 9, Issue 7 , 2015 , Pages 917-932 ; 17518628 (ISSN) ; Solouk, V ; Shayesteh, M. G ; Sharif University of Technology
Abstract
This study presents an efficient fractional frequency reuse scheme for macrocell network which uses six directional antennas to cover the outer region and analyses the performance. Cross-tier interference between macrocell and femtocell networks leading to throughput and outage probability degradation is a major issue in two-tier networks when femtocells are deployed in co-channel with macrocells. In this study, the received interference from the macrocell network to femtocell network is analysed. Then, based on the degree of received interference, an algorithm for orthogonal resource allocation to femtocells with low cross-tier interference is presented. According to the introduced scheme,...
Resource allocation and power control for underlay device-to-device communication in fractional frequency reuse cellular networks
, Article Telecommunication Systems ; 2016 , Pages 1-21 ; 10184864 (ISSN) ; Khazali, A ; Kalbkhani, H ; Shayesteh, M. G ; Solouk, V ; Sharif University of Technology
Springer New York LLC
2016
Abstract
The current state of device-to-device (D2D) communication in the presence of cellular network addresses two major challenges of interference as well as throughput inadequacy. Specifically, a D2D communication underlaying fractional frequency reuse (FFR) cellular network exhibits rather high interferences due to higher occurrence of band crossing within a shared spectrum. However, due to the considerable impact of D2D communications on spectral efficiency and system capacity, the remedy for those issues may include efficient techniques of interference mitigation and average spectral efficiency maximization. In this paper, we propose a resource block (RB) allocation scheme to reduce the...
Resource allocation and power control for underlay device-to-device communication in fractional frequency reuse cellular networks
, Article Telecommunication Systems ; Volume 65, Issue 4 , 2017 , Pages 677-697 ; 10184864 (ISSN) ; Khazali, A ; Kalbkhani, H ; Shayesteh, M. G ; Solouk, V ; Sharif University of Technology
Springer New York LLC
2017
Abstract
The current state of device-to-device (D2D) communication in the presence of cellular network addresses two major challenges of interference as well as throughput inadequacy. Specifically, a D2D communication underlaying fractional frequency reuse (FFR) cellular network exhibits rather high interferences due to higher occurrence of band crossing within a shared spectrum. However, due to the considerable impact of D2D communications on spectral efficiency and system capacity, the remedy for those issues may include efficient techniques of interference mitigation and average spectral efficiency maximization. In this paper, we propose a resource block (RB) allocation scheme to reduce the...
Relay selection for multi-source network-coded D2D multicast communications in heterogeneous networks
, Article Wireless Networks ; Volume 26, Issue 8 , 2020 , Pages 6059-6076 ; Shayesteh, M. G ; Sharif University of Technology
Springer
2020
Abstract
Multicast service is considered as a useful transmission mode for future mobile social services to deliver the traffic to multiple mobile users simultaneously. Device-to-device (D2D) multicast communication enables multiple proximate users to share the contents of their common interests directly. This paper aims to present a relay selection scheme for multi-source network-coded D2D multicast communication underlying heterogeneous cellular network which consists of macrocells and femtocells. We propose two methods for selecting efficient relays from the set of femtocell base stations (FBSs). The first method, named destination-blind relay selection, identifies those idle FBSs that can...