Security Issues of Wireless Communication Networks
Alimul Haque
Dept. of Physics, V. K. S. University, Ara-802301, India
Email: [email protected]
A. K. Sinha
Dept. of MCA, V. K. S. University, Ara-802301, IndiaK. M. Singh
Dept. of Physics, V. K. S. University, Ara-802301, IndiaN. K. Singh
Dept. of Physics, V. K. S. University, Ara-802301, IndiaAbstract – Wireless Communication Networks have attracted a lot of interest in the research community due to their potential applicability in a wide range of real-world practical applications. However, due to the distributed nature and their deployments in critical applications without human interventions and sensitivity and criticality of data communicated, these networks are vulnerable to numerous security threats that can adversely affect their performance. These issues become even more critical in wireless sensor networks (WSNs) in which the sensor nodes have the capabilities of changing their transmission and reception parameters according to the radio environment under which they operate in order to achieve reliable and efficient communication and optimum utilization of the network resources. Recent development in the fields of wireless technologies have greatly benefited mankind, but rapid growth of these technologies have also contributed to unethical practices by individuals who are bent on using the technology to exploit others. Due to the low cost and convenience of deploying wireless networks, they have replaced wired networks in many fields of application. This shift from wired to wireless networks invalidates some established security concepts that rely on the physical inaccessibility of wired connections, as the nature of radio propagation makes it possible to attack wireless networks from outside the established perimeter protection. Such security issues have been increasing in number and complexity over the past few years. Hence there is a need to have comprehensive understanding of security issues and its countermeasures. The purpose of this survey is to do a comprehensive study of these issues in order to create awareness about the various types of threats and their mode of actions so that appropriate countermeasures can be initiated against such issue especially focuses on highly challenging Wireless ad-hoc networks.
Keywords– Wireless Networks, Ad-hoc Networks, Cellular Networks, Jamming, Security.
I. I
NTRODUCTIONWireless networks have found wide acceptance in many industries such as military, healthcare, business, manufacturing, retail, and transportation. These systems are used in various architecture like including fixed networks, cellular networks, and Ad-hoc networks. Fig.1 shows different architecture of cellular and ad-hoc networks. Especially Ad-hoc networks are facing huge amount of unauthorized access. The challenges posed by the industries to each of these technologies are unique, especially for healthcare and military applications.
Over the last decade, wireless communication networks have attracted a lot of interest in the research community due to their wide range of potential applications. A WCN consists of thousands of small devices each with sensing, processing, and communication capabilities to monitor a
real-world environment. These are envisioned to play an important role in a wide variety of areas ranging from critical military surveillance applications to forest fire monitoring and building security monitoring. [1] Most of the WCN deployments operate in the unlicensed ISM bands (2.4GHz).
Some other small range wireless protocols like Wi-Fi, Bluetooth etc. also use the same band. This has led to overcrowding in this band with the increasing deployment of WCN-based applications. As a result, coexistence issues in the ISM bans have attracted extensive research attention.
Keeping this emerging trend of technology in mind, this survey intends to provide a panoramic view of security related issues in WCNs with particular focus on WSNs and WMNs. In the following sections, we present an extensive discussion on various security issues in WSNs and WMNs and present their appropriate defense mechanisms based on the current state of the art.
Traditional WCNs are vulnerable to various types of attacks. These attacks can be broadly categorized into the following types : (i) attacks on secrecy and authentication, (ii) attacks on network availability, and (iii) stealthy attacks on service integrity. Modern cryptographic mechanisms can prevent attacks on the secrecy and authenticity of the messages from hackers attacks such as eavesdropping, packet replay attacks, and modification or spoofing of packets. These attacks are known as the denial of service (DoS) attacks. In stealthy attacks, an attacker compromises a sensor node and injects false data. DoS attacks, if launched successfully, can severely degrade the performance of WSNs.
Fig.1. Cellular network and Mobile ad hoc network
A.
Confidentiality
This is mainly based on cryptographic mechanisms like stream or block ciphers. In this technology hacker or attacker is not be able to fetch the messages transmitted between two parties.
B.
Availability
Availability is most important service in the digital world. DOS attacks always disturb services.
C.
Authentication
Authentic users can access the information or data after verification of their status. It includes entity and data-origin authentication. It is usually achieved by authentication protocols. Attackers are unable to access data.
D.
Integrity
Data and information should be encoded during transmission. Ensure that transmitted data is decoded after reaching the destination as it has been sent from the source.
E.
Access Control
It provides the facility to limit and control access to devices and applications via communication links.
F.
Non-repudiation
It gives guarantee that neither the sender nor the receiver of a message is able to deny the transmission.
II. S
ECURITY INW
IRELESSA
D-
HOCN
ETWORK Ad- hoc networks are new paradigm of networks offering unrestricted mobility without any underlying infrastructure. An ad-hoc network is a collection of autonomous nodes or terminals that communicate with each other by forming a multi-hop radio network and maintaining connectivity in a decentralized manner. Each node functions as both a host and a router. More critically, the network topology is in general dynamic, because the connectivity among the nodes may vary with time due to node departures, new node arrivals, and the possibility of having mobile nodes[4].There are five subset of wireless ad hoc networks: Wireless Sensor Networks (WSNs), Unattended Wireless Sensor Networks (UWSNs), Wireless Mesh Networks (WMNs), Delay Tolerant Networks (DTNs) and Vehicular Ad-hoc Networks (VANETs). Since these networks share many features, for the sake of clarity and completeness, we will first introduce the main security challenges common to all wireless ad-hoc networks.
WSNs, UWSNs, WMNs, DTNs and VANETs
Although sharing many common traits, different network technologies present distinctive features, due to specific requirements and challenges imposed by their application setting. The main characteristics of the types of networks addressed in this paper are highlighted in Table I, and briefly summarized hereunder. WSNs consist of a (generally large) collection of resource-constrained autonomous sensor nodes, appointed to monitor the environment and report the sensed information to one or more trusted gateway nodes, called sinks. Unattended WSNs (UWSNs) are characterized by the intermittent
presence of the sink, which generally prevents direct offload of the sensed data, requiring a secure and distributed storage infrastructure. Wireless Mesh Networks (WMNs) refer to the ensemble of technologies enabling the interaction of different type of networks. The challenge resides in providing a certain level of security despite having to deal at the same time with many technologies. Delay Tolerant Networks (DTNs) are characterized by the opportunistic contacts and the intermittent connectivity of their nodes. Finally, Vehicular Ad-hoc Networks (VANETs) are mobile ad-hoc networks designed to have vehicles as mobile nodes.[5]
Table I: Distinctive Features of Several Ad-Hoc Networks Network Distinctive feature
WSNs Very high number of nodes, limited computational power
UWSNs Intermittent sink
WMNs Integration of many networks
DTNs Opportunistic contacts and intermittent connectivity
VANETs Vehicles as mobile nodes
A.
Wireless Mesh Networks
Wireless mesh networking has emerged as a promising technology to meet the challenges of the next generation wireless communication networks for providing flexible, adaptive, and reconfigurable architecture and offering cost-effective business solutions to the service providers [6]. The potential applications of wireless mesh networks (WMNs) are wide-ranging such as: backhaul connectivity for cellular radio access networks, high-speed wireless metropolitan area networks (WMANs), community networking, building automation, intelligent transportation system (ITS) networks, defense systems, and city-wide surveillance systems etc [7].
Fig.2. Architecture of Wireless Mesh Network
1. Characteristics of a WMN
■ WMN‘s are considered to be a subclass of ad hoc networking (unlike in Mobile Ad Hoc Networks, MANET‘s)
■ WMN‘s have properties of an autonomic system: i. Self-Configuration
ii. Self-Healing (redundant, decentralized, no central point of failure)
iii. Self-Management iv. Self-Optimization
■ High overall capacity: i. Spatial diversity ii. Power management iii. Important constraints:
Shared bandwidth & interference Number and location of nodes
2.
Applications of Wireless Mesh
Networks
i. Broadband Internet Accessii. Indoor WLAN Coverage iii. Mobile User Access iv. Community Mesh Network
v. City-wide Wireless Coverage (Blanket) vi. Spontaneous Mesh Network
vii. Industry Breakdown
B.
Wireless Sensor Networks
A Wireless Sensor Network (WSN) consists of sensors-equipped nodes, called motes or simply sensors, sensing the environment and reporting the collected data to one or more trusted gateway nodes, called sinks. Sinks sometimes play a coordination role, but the frequency and impact of their presence in the network is highly variable according to the setting [8], so motes are often required to self-organize in a distributed way.
There are two specifications available for WSN communication: IEEE 802.15.4 [9] and ZigBee [10]. The first is a standard for low-rate wireless personal area networks that was developed by IEEE and contains a number of security suites. Basically, it provides access control, integrity, confidentiality and replay protection; however, it does not deal with authentication. ZigBee is built upon IEEE 802.15.4. This standard defines a communication layer at level 3 and above in the OSI model. Its main purpose is to create a network topology (hierarchy) to let a number of devices communicate among them, and to add extra communication features such as authentication, encryption and association. The ZigBee network layer natively supports star, tree and generic mesh networks.
III. A
PPLICATIONS OFW
IRELESSS
ENSORN
ETWORKSDue to their versatility, WMNs can efficiently satisfy the needs of multiple applications. It is likely that other applications will emerge as the technology matures. Although several architectures for WMNs have been proposed based on their applications .[11,12]
Wireless sensor network has lots of applications. i. Environmental data collection
ii. Military applications iii. Security monitoring
iv. sensor node tracking application v. Health care monitoring application vi. Process Management
vii. Home application viii. Hybrid Network
1. Characteristics of a WMN[13]
Ability to cope with node failures Mobility of nodes
Ease of use
Cross-line design
Ability to withstand harsh environmental conditions Scalability to large scale of deployment
Table II shows various attacks and countermeasures in WSNs and WMNs.
IV. S
ECURITYV
ULNERABILITIES INWCN
S Wireless Communication Network is a prevailing technology that shows great promise for diverse ultramodern applications both for mass public and intelligence. Security in wireless networks is still in its born position, as little consideration has been made to this area by the research community, due to this ignorance, Wireless Network Communication still facing numerous issues and challenges.Today, the most demanding area of wireless networking is ad-hoc wireless networks, but unfortunately any hacker can easily get the access on the network resources and disrupts the communications due to low security. Some of these issues are as follows:
In many cases cryptographic-based solution for detection the intruder in ad-hoc networks are ineffective [14].
Attacks on wireless ad hoc network specially on routing protocols upsets network performance and reliability [15].
No response method and limitations to handle wormhole attacks in Wireless Ad-hoc Networks (WANs) [16]. Many existing ad-hoc routing protocols concern only the
length of the routers [17].
The Wireless Sensor Network gateway forms a single point of breakdown for the back-to-back sensor network infrastructure [18].
After deployment of network, sensor nodes remain unattended which is a root cause of security lapses [19]. The existing location tracking methods have their own
boundaries in tracing wireless intruders[20].
Major threat and challenges of wireless communications are still not considered in IEEE 802.11i revised specification[21].
Ad-hoc Wireless Sensor Networks deployment for monitoring physical environments are still in vulnerable zone[22].
There is no common model to guaranteed security for each layer in a Wireless Sensor Networks (WSNs) [23]. Current security Solutions for wireless Sensor networks
are not feasible against all Prevailing security threats [24].
Protection mechanism in wireless sensor network is still adolescent age [25].
The current protocols for data link layer & network layers are not adequate for handling various security threats in WSN [26].
The existing security measures for wireless sensor networks (WSN) are insufficient[27].
There is no proper visualization technique present for wireless communications[29].
Security model for wired network not necessarily effective for wireless networks[30].
Compressed Real time Transport Protocol (CRTP) is not appropriate for wireless links, that have a very high and erratic bit error rate (BER)[31].
Inadequate security integration scheme for heterogeneous networks[32].
The current wireless smart home system has range limitation issue[33].
Table II: Summary of Different Attacks on WSNs and WMNs and Their Countermeasures [5,11]
WIRELESS SENSOR NETWORKS WIRELESS MESH NETWORKS
Layer Attacks Countermeasures Layer Attacks Countermeasures
Physical
Jamming
Tampering
Detection techniques, proactive, reactive, and mobile agent based Countermeasures
Tamper-proofing, software tamper detection, sensor
monitoring
Physical Jamming
Spread-spectrum, priority messages,
lower duty cycle, region mapping, mode change
Link
Collision Exhaustion Unfairness Sleep deprivation
Forward error-correcting codes Rate limitation
Error-correcting codes
Anti-replay protection, strong link-layer authentication, and
broadcast attack protection
MAC CollisionExhaustion Unfairness
Error-correction code Rate limitation Small frames
Network & routing
Routing information Hello flooding
Black hole
Sink hole attack
Selective forwarding Wormhole attack Sybil
Authentication, MAC
Authentication, bi-directionality checking, signal strength
Authentication, REWARD, watchdog and pathrater
Authentication, monitoring, secure routing
Authentication, IDS, multi-hop acknowledgments, multipath routing
Authentication, packet leashes Authentication, radio resource testing, key validation for
random key pre-distribution, position verification
Network
Spoofed routing information & selective forwarding Sinkhole Sybil
Wormhole Hello Flood
Ack. Flooding
Egress filtering, authentication, monitoring
Redundancy checking Authentication, monitoring, redundancy
Authentication, probing Authentication, packet leashes by using geographic and temporal information
Authentication, bi-directional link
authentication verification
Transport Flooding
Desynchronization
Client puzzles, cryptographic techniques
Authentication
Transport SYN Flooding
De-synchronization
Client puzzles, SSL-TLS authentication, EAP
Privacy & Secrecy Physical
Network Eavesdropping
Traffic analysis Cryptographic techniquesRandomized communications
Privacy Traffic analysis, Attack on data privacy and location privacy
Homomorphic encryption, Onion routing, schemes based on traffic entropy computation, group signature based anonymity schemes, use of
pseudonyms.
V. S
ECURINGW
IRELESSN
ETWORKSThere are some important techniques to avoid hackers. [34]
A.
Use of Encryption
This is one of best way to secure wireless network from intruders is to encrypt, or scramble, communications over the network. Most wireless routers, access points, and base stations have a built-in encryption mechanism. If your wireless router doesn’t have an encryption feature, consider getting one that does. Manufacturers often deliver wireless routers with the encryption feature turned off.
B.
Use anti-virus and anti-spyware software, and a
firewall
To avoid virus in the computers on a wireless network need the same protections as any computer connected to the Internet. Install anti-virus and anti-spyware software, and keep them up-to-date. Always firewall option should be turn on.
C.
Turn off identifier broadcasting
broadcast this information if the person using the network already knows it is there. Attackers can use identifier broadcasting to home in on vulnerable wireless networks. Turn off the identifier broadcasting mechanism if our wireless router allows it.
D.
Change the identifier on our router from the
default
Hackers know the defaults IDs from various sources and can use them to fetch our network. We should change our identifier and remember to configure the same unique ID into our wireless router and our system so they can communicate. It is much better to use at least 10 characters long password. It is very tough to break longer password.
E.
Change our router’s pre-set password for
administration
Hackers know all new manufactured wireless router default password. For the security point of view we should change those passwords and keep longer password. Longer password is very tougher to crack.
F.
Allow only specific computers to access your
wireless network
All system has own unique Media Access Control (MAC) address. Wireless routers have a special mechanism, which allows only devices with particular MAC addresses access to the network. Some hackers have mimicked MAC addresses, so don’t rely on this step alone.
G.
Turn off your wireless network when you know
you won’t use it
If there is no need of router, then shut down. Hackers cannot access a wireless router when it is shut down.
VI. C
ONCLUSIONIn this survey paper, we look into the security issues and challenges in wireless communications, particularly in ad-hoc communications. Wireless ad-ad-hoc networks is an umbrella name that gathers very diverse network technologies with the common features of being self-organized and wireless[5]. Especially WSNs and WMNs have become an important focus area of research in the recent years owing to their great potentials in realizing numerous next-generation wireless services with stringent QoS guarantees and with high mobility support for the users. Driven by the increasing demand for rich, high-speed and bandwidth intensive content access, recent research has focused on developing high performance communication protocols for such networks. This paper has made a comprehensive presentation on the various attacks on different layers of the communication protocol stack of WSNs and WMNs. While highlighting various vulnerabilities in the physical, link, network, transport and application layers.
A
CKNOWLEDGMENTThe authors are grateful to UGC, New Delhi,India for providing financial assistance for this research grant.
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A
UTHOR’
SP
ROFILEMd. Alimul Haque
is a Research Scholar at V.K.S.University, Ara, India . He received his Master degree in Computer Science. His research has been focused on Security issues in Wireless Communication Networks specially WiFi, WiMAX and Bluetooth. His research has led to publications of numerous journals and conference articles. He has been an active member of Cryptography Society of India, Kolkata and The National Academy of Sciences, Allahabad, India.
Anil Kumar
obtained the master degree in Computer Science from IGNOU, New Delhi and Ph.D. degree from V.K.S. University, Ara on “on Data Mining and Network Technology” in 2013. His recent research interest include Security in Data Communication Networks and Data Mining.
Dr. K. M. Singh
Professor & Head, Department of Physics and Director of MCA Course in V.K.S. University, Ara. He obtained his M.Sc. degree in Physics from Patna University, Patna in 1977 and did his Ph.D. in Plasma Physics. He has more than 40 research publications in reputed National & International journals. He is the life member of different academic and Research Societies of India and abroad. His current interests are focused on Theoretical Physics and Computational Physics.
