Wireless Network Security

Bettye McKinnonMichael Schultz

Josh WatsonCIS4360

12/06/2006

Wireless Network Security

Network security is one of the most important (if not THE most important) aspects of network

administration. Nothing can be more destructive to a network than poor security. In addition, unlike

wired networks, wireless network signals are broadcast throughout an entire area, making signal interception simple. Therefore, while all network

security measures are still implemented, the backbone of Wireless Network Security is

obviously encryption.

IEEE● Institute of Electrical and Electronics Engineers.

● Developers of industrial standards.

● Established standards for wireless networks.

● Created and maintained by the IEEE 802 LAN/MAN Standards Committee

● Named “802” as a referene to the date which the committee first met, February 1980.

IEEE 802● IEEE 802.1 Higher layer LAN protocols● IEEE 802.2 Logical link control● IEEE 802.3 Ethernet● IEEE 802.4 Token bus

● (disbanded)● IEEE 802.5 Token Ring● IEEE 802.6 Metropolitan Area Networks (disbanded)● IEEE 802.7 Broadband LAN using Coaxial Cable

● (disbanded)● IEEE 802.8 Fiber Optic TAG

● (disbanded)● IEEE 802.9 Integrated Services LAN

● (disbanded)

IEEE 802● IEEE 802.10 Interoperable LAN Security

● (disbanded)● IEEE 802.11 Wireless LAN

● (Wi-Fi certification)● IEEE 802.12 demand priority● IEEE 802.14 Cable modems

● (disbanded)● IEEE 802.15 Wireless PAN● IEEE 802.13 (not used)● IEEE 802.15.1 (Bluetooth)

IEEE 802● IEEE 802.16 Broadband Wireless Access

● (WiMAX certification)● IEEE 802.16e (Mobile) Broadband Wireless

Access● IEEE 802.17 Resilient packet ring● IEEE 802.18 Radio Regulatory TAG● IEEE 802.19 Coexistence TAG● IEEE 802.20 Mobile Broadband Wireless Access● IEEE 802.21 Media Independent Handoff● IEEE 802.22 Wireless Regional Area Network

802.11

● Wireless LAN/Wi-Fi standard.● Wi-Fi

– Wi-Fi Alliance® tests products for IEEE 802.11 compatibility

● Standard is frequently encountered– LAN– Routers– Ethernet

● Many 802 standards have been absorbed by the 802.11 standard.

IEEE 802.1x

● IEEE 802.1X is the original IEEE 802 standard for port-based Network Access Control authentication

● Authenticates users attempting to accesss through a LAN port

● Standard used poor encryption, and was updated to IEEE 802.11i

IEEE 802.11i

● Improvement upon IEEE 802.1x

● Still employs all specifications of IEEE 802.1X, except:

● Employs WPA (Wi-Fi Protection Access) encryption instead of WEP (Wired Equivalent Privacy) encryption.– WEP shown to be easily broken.– Will cover this topic again later

Wireless Encryption

● WEP Encryption– Wired Equivalent Privacy– Original IEEE encryption sandard– Not very secure– With proper software, can be broken within

several minutes ( < 3 )

● WEP2– Larger encryption key– Larger initialization vector

● Prevents key collisions– Great improvement on WEP

Wireless Encryption

● WPA– Wi-Fi Protected Access– Developed by WiFi Alliance to replace WEP– Designed for use with IEEE 802.1X

authentication servers● Issues unique keys to each user, or● pre-shared key, where every user is issued the same

password

● WPA2– Employs much more powerful encryption

algorithm

Attacks on Wireless Networks

The following are a few examples of some well-known means of attacking a wireless network. However, this list is by no means exhaustive.

New methods of attacking wireless networks appear frequently. Network Administrators must stay up

to date with wireless network attacks.

Attacks on Wireless Networks

● Insertion Attack– Occurs when the attacker is able to access the

network without authentication.

● DoS Attack– Denial of Service. Occurs when attacker(s)

overwhelm the server with requests.

● Interception– Occurs when an attacker gains access to a

network and eavesdrops on the network's traffic.

Attacks on Wireless Networks

● Peer-to-Peer / Client-to-Client Attacks– Occurs when an attacker directly attacks a user

of a network, as opposed to just the network itself.

● MAC Spoofing– Occurs when an attacker monitors the traffic of a

network for MAC Ids, which can then be used to access a network under a false identity.

– Original owner of MAC ID may be blamed for attacker's damage. Good way for disgruntled employee to “get back at” another employee.

Attacks on Wireless Networks

● Man-In-The-Middle– One of the more sophisticated attacks. – Somewhat similar to Spoofing– Attacker sets up a terminal that users are fooled

into logging in to. The attacker then connects to the actual server, giving the users the impression that they have logged onto the system without incident.

– Attacker may now observe all traffic running between his or her new “proxy” server.

– Difficult attack to thwart. This attack is not for amateurs.

Securing a Network

● Change default password– !!!!!– Commonly overlooked– Default usernames and passwords are

commonly known

● Disable SSID Broadcast. – Most routers broadcast the network's SSID

(Service Set Identifier), making the network visible to anyone within range.

Securing a Network● Enable WPA/WPA2 encryption instead of

WEP, which is easily broken.

– WPA: “Wi-Fi Protected Access”● Employs RC4 encryption, which is essentially useless

against experienced crackers.● With easily available software, RC4 can be broken in

under 3 minutes.

– WEP “Wired Equivalency Privacy”● Employs an AES-based algorithm.● Considered completely secure.● Has had several improved versions, WPA2 and

WPA+.

Securing an Network

● Use MAC filtering for access control. This will allow access to only the addresses specified by the user.– Beware of MAC filtering attacks

Securing a Network

● Disable remote administration– Or specify a dedicated IP address for

implementing remote administration, if necessary.

● Limit the number of users allowed to access the network simultaneously.– Easier to keep track of possible intruders– Excellent way to find stolen/spoofed MAC

addresses.

Securing a Network

● Also, all security measures associated with wired networks should also be employed.– Password security.– Employee awareness of social engineering.– Maintain confidentiality, integrity, and availability.– Auditing– Appropriate means of authentication– Basically, all of the security measures we have

learned this semester also apply to wireless networks.

Securing a NetworkOf course, there are many other security aspects to

consider for every unique network, such as the weather conditions of a geographic area (e.g. -10

deg F during Winter in Chicago, or 120 deg F during the Summer in Phoenix). Also,

consideration should be given to a system's succeptability to natural disasters (buried under a building in San Francisco after an earthquake.)

For instances such as these, many other security measures must be implemented. However, time

does not allow for us to cover such issues in great detail

Summary

Poor network security can ruin lives. Businesses can be destroyed, a person's credit destroyed after their

identity has been stolen, being arrested/charged with illegal activity performed by an intruder, among many other things. The importance of

security cannot be emphasized enough.Networks of course pose the greatest security threat,

since information is passed around and many users share many computers.

Summary

With the advent of wireless networks, an entirely new security threat has emerged. Whereas a wired network sends information directly to the recipient,

wireless networks are easily intercepted and breached. While user authentication is very

helpful, the only true means of countering wireless intrusion is through encryption. So remember,

while security may be costly, it must be implemented to the fullest potential of the

resources available to you.

Summary

“Just because you are paranoid doesn't mean they aren't after you.”

-Aleksandr Solzhenitsyn

The End.

References

www.practicallynetworked.com/support/wireless_secure.htm

en.wikipedia.org/wiki/Wireless_security

en.wikipedia.org/wiki/Wired_Equivalent_Privacy

en.wikipedia.org/wiki/IEEE_802.11

References (con't)

en.wikipedia.org/wiki/Wi-Fi

en.wikipedia.org/wiki/Wi-Fi_Protected_Access

techdir.rutgers.edu/wireless.html

www.onlamp.com/pub/a/security/2006/03/30/what-is-wireless-security.html