Mrs. Jyoti Upadhyay
Abstract:
Wireless technology is an alternative for computer networks that use cables. A wireless network uses microwave and other radio signals for transmitting data. A wireless network offers advantages and disadvantages compared to a wired network. Advantages of wireless include mobility and elimination of unsightly cables. Disadvantages of wireless include the potential for radio interference due to weather, other wireless devices, or obstructions like walls. Wireless networks add an extra level of security complexity compared to wired networks. Security in wireless networking is becoming more critical as the use of wireless technology is increasing in popularity. This security issue applies irrespective of whether it is a laptop connecting to
a wireless network, or setting up a wireless digital media player as part of a home entertainment solution. We use all sorts of encryption already. Do we have to worry about yet more security? Security mechanisms at the application layer are sent encrypted but the network layer routing and protocol information is generally sent without encryption. Many, if not most, security protocols that people are familiar with, VPN, SSL, and IPSec work at the application network layers Wireless Security
Wireless security has lots in common with security in fixed networks as the basic rules for the same .wireless communication have some specific characteristics over the fixed communication that have to be considered in the sense of security. Those are:
- Transmission through air: anyone can listen (privacy)
- Radio waves do not stop to corporate walls or to other artificial borders (privacy)
- Spectrum of the radio channels is limited (availability)
- Without network coverage no services available (availability)
Keeping data private is a big issue for any wireless network. In the days of voice only communications, the greatest worry was that an eavesdropper could listen to a private conversation, but mobile commerce makes security even more critical -if people are going to entrust their bank account to technology, it has to be secure.
Security is an important enabler for the development, adoption and the usage of the mobile and wireless technologies and services.
Attack Methods on wireless network
Human Error: Security of computers and systems always interacts with users, and as commonly the user is a human, it is the security of the interaction between human and the computer or system. One does not need to look far to find an easy example of this. One such example would be a user that prints out confidential information from a company's secure intranet and then forgets the paper to a common printer or even to an airport lounge. Even though the system was secure, the user made the information insecure by carelessly handling it. The importance of security policies and rules is increasing as companies implement their mobile strategies and deploy mobile devices into business usage.
Improper Design: Improper or unknown boundary definitions constitute another possibility for network design error. Wireless network interface cards (NIC) and routers come with a variety of antennas. Some antennas broadcast in a single direction, and while they are not very accommodating to the surrounding area, they definitely help narrow the boundaries. The real danger comes in Omni-directional antennas that broadcast in all directions, providing easy-access to the wireless network. Insecure-by-default hardware, unqualified system administrators and coverage boundaries that are out of control make up the key characteristics of faulty wireless network design.
Basic Defense
WEP: Wireless Encryption Protocol was integrated into wireless devices with a primary goal of preventing casual eavesdropping on a network. Much like crosstalk can occur among wireless telephones, the same effect could take place in getting packets distorted among common pathways on a wireless network. WEP performs this function rather well, but the second purpose of WEP is where the protocol falls short. The second purpose of WEP is to prevent unauthorized access to wireless networks. Now don't be mistaken, WEP will prevent uninformed and unskilled crackers from accessing a wireless network. However, it doesn't take much effort at all to break WEP. While the methods of attack that can be used are too technical for our purposes, it's important to understand their existence.
One method comes in the form of brute force attacks, which simply break down WEP's functionality forcing errors within the protocol and eventually causing it to open a door on its own. Other algorithms exist such as the dictionary attack. Dictionary attacks use several common keys, or a dictionary of keys stored over time to try guessing a different key until one works. Deeper hacking methods involve exploiting what is called the IV (Initialization Vector) vulnerability. The Initialization Vector can be used to trick WEP systems, and manipulate them into revealing keys or simply breaking down defenses by causing confusion within the WEP transmissions. A few improvements have been attempted in regards to WEP mainly in the form of WEP2. WEP2's primary attempt at improvement came in making the IV key even longer. However, industry experts agree that this not only doesn't make WEP more secure, but also exposes even greater security threats to users.
WEP does a fine job at keeping novice hackers from spying on your valuable data. However, armed with the right tools, WEP has been proven to be flawed and vulnerable. We recommend that network administrators make use of WEP but emphasize that primary dependence not be placed on this protocol for security. WEP should be used, even according to wireless product makers like Net gear, but certainly not by itself.
Even with its inherent weaknesses, Wireless Encryption Protocols or WEP is still a good method for preventing attackers from capturing your network traffic. Less-experienced hackers will probably not even attempt to capture data packets from a wireless network that is broadcasting using WEP. Even if a hacker possesses the skills and tools necessary to crack WEP, it can be an extremely time-consuming process, especially when dealing with the newer 128-bit specification, which requires in excess of 500,000 captured data packets to even begin the cracking process. Not only is WEP a good way to ward off many would-be attackers, it is strengthened when used with other security techniques.
Virtual Private Networks: Virtual Private Networks, or VPNs, facilitate security over public connections through encryption techniques and other various security methods. A VPN works by sending data through a "tunnel" which cannot be penetrated by paths outside of the tunnel. This is done through the use of tunneling protocols such as Layer Two Tunneling Protocol, which encrypts the data at the sending end, and decrypts it at the receiving end. In order for a VPN to function properly, network users must install a small client application on their computers, which is used to decipher and help facilitate the encoded communication.
A protocol called IPSec is the de facto standard for VPN's over the Internet. IPSec defines the way secure data packets are structured through its three major components: the Authentication Header (AH), the Encapsulating Security Payload (ESP), and Internet Key Exchange. AH is responsible for verifying that packets have not been altered between the sender and receiver. It does not provide any encryption-it simply verifies that the data sent through a VPN is accurate. Encryption is handled instead by ESP, which can employ a variety of techniques such as Data Encryption Standard (DES) or Secure Hashing Algorithm (SHA). Each of the three components can operate in different modes and can be combined in different ways, which allows customizable security through implementation. For example, many IPSec VPNs either do not use AH at all, or use a combination of AH and ESP.
VPNs fit into three categories: network-to-network, host-to-network, and host-to-host. Network-to-network VPNs are used to securely transmit data between two LANs over a public network. Host-to-network VPNs connect a single user to a LAN securely, over a public network. Finally, host-to-host VPNs involve two single clients communicating securely with one another over a public network.
Conclusion
We have seen benefits and risks, strengths and weaknesses of wireless technology, and we have learned some ways in which they are attacked and defended. As wireless technology continues to expand its presence across the globe, there are sure to be many fascinating changes that will affect the way we live and work--and it will be important to have an understanding of the both the possibilities and dangers that come with it. Without a doubt, there will be improvements made to wireless security. I hope that the knowledge contained in these pages provides a solid understanding of wireless security, and a foundation on which to build and adapt knowledge as changes come about.
References
Anderson, Christoffer, GPRS and 3G Wireless Applications, John Wiley & Sons.
Dornan, Andy, The Essential Guide to Wireless Communication Applications.
Sharma, Chetan, Wireless Internet Enterprise Applications, John Wiley & Sons.
Schneier, Bruce Secrets and Lies, Digital Security in a Networked World, John Wiley & Sons.
802.11 Wireless Networks: The Definitive Guide Creating and Administering Wireless Networks ByMatthew Gast
3G Wireless Networks by Daniel Collins and Clint Smith
3G Evolution, Second Edition: HSPA and LTE for Mobile Broadband... by Erik Dahlman
Wireless LAN security By Krishna Sankar, Sri Sundaralingam, Andrew Balinsk
http://www.deltawavecomm.com/,
Asst.prof. (comp sc.)
Swami swaroopanana institute of ecucation, hudco, Bhilai (c.g.)
email : upadhyaya.jyoti@gmail
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