1 C-DAC/Kolkata C-DAC All Rights Reserved Computer Security.

1C-DAC/Kolkata C-DAC All Rights Reserved

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Computer Security


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• This presentation is intended to inform the audience about the dangers associated with a computer network devices and it is not a demonstration of any Hacking .


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Demos

• Wireless Security

• Web Security


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INDEX

• Introduction

• A Step-by-Step process of Wireless Communications

• Prevent Your Network from Getting Hacked


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INTRODUCTION


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Wireless Internet• It is internet access without the use of wires.

• Instead it uses radio frequency bands to exchange information between your computer and the Internet within a range .


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Types of Wireless Security


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Types of Security• OPEN : No security configured

– Obviously not advised

– Data is in the air in plain text and anyone can read it

• WEP : Wired Equivalent privacy – Very week and not recommended

– Used in Open and Shared-Key Authentication


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Types of Security…

• WPA: Wi-Fi Protected Access – Much better than WEP– Pre shared Key concept used– Encryption Algorithm used TKIP– Easy to setup, as easy as WEP– Available in all the common wi-fi routers– A must for all home users– Will take a long time to break in


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Types of Security…

• WPA2: Advance Wi-Fi Protected Access – Better than WPA– Used AES as Encryption System– Takes little more pain to setup– Advised in corporate environments– Strong encryption and authentication support


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Wireless Security Standards


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Description of WEP ProtocolWEP relies on a shared secret key (40 bit/128 bit) which is shared between the sender (client) and the receiver (Access Point).

Secret Key - to encrypt packets before they are transmitted

Integrity Check - to ensure packets are not modified in transit.

The standard does not discuss how shared key is established. In practice, most installations use a single key which is shared between all mobile stations and access points.

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How to configure WPA• Open the configuration of your wi-fi device• Go to wireless setting• Under security option, select any one

– WPA– WPA-PSK– WPA-Personal– WPA2-Personal

• Set a complex password• Change the login password of the wireless router.• Done


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Look for this


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A Step-by-Step process of Wireless Communication


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A little info…

• For Connecting with a AP user render data segment called Beacon frames.

• After connected with AP the data segment is called Packet.


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More info…

• Depending on how long the computer is connected, it can generate a certain number of packets per day.

• The more users that are connected to one access point, the more packets are generated.


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First…• You must locate the wireless signal

• This can be done by using your default Windows tool “View Available Wireless Network”


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Second…

• Once you located a wireless network you can connect to it unless it is using authentication or encryption.

• If it is using authentication or encryption then for the next step a Cracking tool can be use for WEP keys.


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• Once enough packets recovered it will then captured information gathered from the packets and crack the key giving you access.

Third….


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Prevent Your Network from Getting Hacked


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Prevent Your Network from Getting Hacked

• Don’t broadcast your SSID . This is usually done during the setup of your wireless router.

• Change the default router login to something else. • If your equipment supports it, use WPA or WPA 2

because it offers better encryption which is still able to be broken but much harder.

• Always check for updates to your router.• Turn off your router or access point when not using it.


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Security Advised

• Change the router login password frequently– At least once a month

• Change the wireless WPA password also– At least once a month

• Avoid temptation to connect to open wireless just looking for free internet.


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Security Advised..

• We can configure DHCP more tightly.– Lets not keep an open pool where any one can

connect– Example

– I have 3 machines in my home (desktop/laptop/phone)

– I’ll create a IP pool of 3 IPs only

– I’ll do DHCP reservation using the MAC of these 3 IP

– Effectively I’m not allowing any outsider machine to connect


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Security Advised..

• We can configure MAC binding.– Allow only MY machines to connect– Many access points support MAC binding– Any other machine will not be able to connect to

my Wi-Fi


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Web Security


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MethodsMan-in-the-Middle Attacks

Stealing Passwords

Trojan Horses

Exploiting Defaults

Wireless Attacks


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Man-in-the-middle(MITM) Attack

MAC(Media Access Control) duplication ARP (Address Resolution Protocol) poisoning Router table poisoning Fake routing tables


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Conclusion

• There is no such thing as 100% percent security when using wireless networks but at least with these few simple steps you can make it harder for the average person to break into your network.


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Thank You

1 C-DAC/Kolkata C-DAC All Rights Reserved Computer Security.

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Transcript of 1 C-DAC/Kolkata C-DAC All Rights Reserved Computer Security.