http://faculty.uml.edu/Tricia_Chigan/Research/CRCN_NS3.html
Cognitive Radio Cognitive Network Simulator (NS3 based)
Table of Contents:
1 Introduction to CRCN
1.1 Backgroundof Cognitive Radio
1.2 Motivation
1.3 WhyBased on NS3?
1.4 CRCNSimulator Overview
2 Simulator Overview
2.1 System Requirements
2.2 Functionality Overview
2.3 Design Overview
2.3.1 Design of CR MAC/PHY
2.3.2 Design of Spectrum Database
2.3.3 Design of Attack Model and its Interface
2.3.4 Design of Spectrum Coordinator and its Interface (under construction)
2.3.5 Example Script for Simulation Configuration
3 CRCN User Guide (under construction)
3.1 Software and Installation
3.2 Examplary Demonstrations
3.3 GUI User Guide
4 Miscellaneous(underconstruction)
4.1 References
4.2 FAQ
4.3 Cognitive Radio Research Group
1. Introduction to CRCN
1.1 Backgroundof Cognitive Radio
CognitiveRadio Cognitive Network (CRCN) is a promising technology that has been studiedin the research area for a long period. With CRCN, the problem of spectrumscarcity and spectrum underutilization might be effectively solved [1]. This isattributed to the Dynamic Spectrum Access/Allocation (DSA) mechanism [2] ofCRCN, which allows the CRCN subscribers to opportunistically occupy thespectrum resources that assigned by the FCC to the licensed networks (primaryusers) avoiding interfering to them. The coexistence of CRCN with primary usersnecessitates the CRCN nodes to be capable of being aware of their surroundingenvironments (e.g., the availability of a specified channel band), which iscalled spectrum sensing [3]. The spectrum sensing is facilitated periodically (e.g.,specified in IEEE802.22 standard [4]). Once the channel bands are detected tobe unoccupied by the primary user, the CRCN may request to access into thesechannel bands. Otherwise, the CRCN immediately vacant the channel bands thatoccupied by the primary user and move to the other available bands. The CRCNcoexists with not only the primary users, but also other CRCNs since multipleCRCNs may work simultaneously over the same available spectrum bands [5]. This resultsin even more complicated design of CRCNs since both interference to the primaryusers and CRCN’s network performance should be optimized simultaneously [6].
Securityis another significant topic considered in the design of CRCNs [7, 8]. Due tothe cognitive features of CRCN (e.g. spectrum sensing and coexistence withprimary users etc.), specific attacks for the CRCNs have been proposed in theliterature, such as Primary User Emulation Attack (PUEA) [9, 10], SpectrumSensing Data Falsification (SSDF) [11, 12], Jamming on Common Control Channel[13, 14] and so on. Without the effective defense approaches to these attacks, theCRCN performance will degrade severely and it may lead to the low spectrumutilization efficiency. Furthermore, the primary network might be interfered bythe CRCN due to the fake spectrum sensing reports caused by the adversaries. Anumber of approaches have been proposed to defending against those attacks. However,considering the deployment of CRCN in reality, novel security challenges willbe found which necessitates more effective and efficient solutions.
1.2 Motivationof upgrading the CRCN simulator
Ascognitive radio research is emerging, more and more researchers are lookingforward to a simulator that is suitable for cognitive radio. However, there isno existing simulator that is suitable for the demand of cognitive radiosimulations. Many researchersimplemented their algorithms for cognitive radios on existing network simulatorsuch as NS-2 [15], OPNET [16], QUALNET [17]. However, since these simulatorsare created for the ordinary wireless network, researchers cannot easilyimplement their cognitive radio algorithms over those simulators. Hence, thereis a demand to extend existing simulators to support cognitive radiosimulators.
Wehave developed a CRCN simulator with NS-2 (http://faculty.uml.edu/Tricia_Chigan/Research/CRCN_Simulator.htm), and this version has been widelyutilized in the academia field. We are attempting to upgrade our CRCN simulatorwith NS-3 [18] according to the following reasons:
1) Securityis one of the important issues in the research of CRCN, we will provide theattack model interface in this updated version for users to evaluate theeffects of their proposed attack models. Some of existing attack models will begiven as example to show how to embed the attacks into the CRCN simulator.
2) Thecoexistence issue of CRCN has been drawing more attention of researchers. Thispropels us to provide the coexisting module interface to the users to evaluatetheir coexisting mechanism.
3) Recently,the development of CRCN has been paid more attention in the industrial fieldwherein a number of realistic constraints are considered. In order to make thenetwork simulation more realistic, we attempt to develop the CRCN simulatorwith a tool which can be easily integrated into the hardware which can beconsidered as a network node. Eventually, a network testbed will be built with thenetwork nodes implemented by the hardware integrated with our CRCN simulator.
1.3 Whybased on NS-3
NS-3[18] inherits many advantages from NS-2, for example: 1) NS-3 is open sourcesoftware, thus any contributions to the NS-3 are accessible by the peoplearound the world; 2) NS-3 provides many radio models such as 802.11, 802.16,802.15.3, 802.15.4. Users can make use of these radio models for cognitiveradio network simulations; and 3) NS-3 has incorporated with different topologyand traffic generators, which enable users to create different simulationscenarios etc.
Comparedwith NS-2, NS-3 has following extra advantages [19, 20]:
1) Asimulation script can be written as a C++ program, which is not possible inNS2.
2) Withmodern hardware capabilities, compilation time was not an issue like for NS2, NS3can be developed with C++ entirely.
3) Ns-3enables the testbed-based researcher to experiment with novel protocol stacksand emit/consume network packets over real device drivers or VLANs. Theinternal representation of packets is network-byte order to facilitateserialization.
4) NS3performs better than NS2 in terms of memory management.
5) Theaggregation system prevents unnecessary parameters from being stored, andpackets don't contain unused reserved header space.
1.4 CRCN Simulator Overview
Thiscognitive radio cognitive network (CRCN) simulator is a software based networksimulator for network-level simulations. It is based on open-source NS-3(network simulator 3). CRCN simulator will be able to support performanceevaluations for the proposed dynamic spectrum resource allocation, powercontrol algorithms, coexistence mechanisms and the adaptive Cognitive Radio(CR) networking protocols such as the CR MAC protocols. The effects of attackmodels can also be evaluated using this CRCN simulator. This simulator uses NS-3to generate realistic traffic and topology patterns. For each node in thissimulator, a reconfigurable multi-radio multi-channel PHY layer is available bycustomizing the spectrum parameters such as transmission power etc.
Figure1. Architecture of CRCN Simulator