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Write code for that program

Plz help me solve this problem.. Qsn: One of the most basic forms of encryption is known as a Ceaser Shift cipher. This type of encryption takes a language and uses and offset of the language to substitutes a different letter for every letter. This offset works in the following way: if an offset of 1 is used, then ?a? is represented by ?b?, ?b? is represented by ?c?, and so on. When we reach the end of the alphabet and a no letter is after the current one, then we wrap around to the beginning of the language. In our current scenario ?z? is represented by ?a?. So, a Ceaser-shift of 11 would be: Original: a b c d e f g h i j k l m n o p q r s t u v w x y z | | | | | | | | | | | | | | | | | | | | | | | | | | Code: l m n o p q r s t u v w x y z a b c d e f g h i j k Note, your encryption schemes should be case insensitive, so both ?A? and ?a? should be encrypted by the same letter. The methods that you write for encryption should be put in a file named Encrypter.java. [a] Write a method called ceaserEncrypt() that accepts one parameter: the name of the file to be encrypted. This method should Ceaser shift the 26 letters of the English alphabet and output an encrypted version of the input file. The offset should be random, so that the shift will not be the same every time the program is run. Given the name of a text file, your program should input the file file1.txt and produce a Ceaser shift encrypted file ceaserFile1.txt (where ?file1? is the name of the file given to the program). Your program should also output a second file file1KeyC.txt that specifies the offset used for encoding. [b] Write a method called ceaserDecrypt() that accepts two parameters: the name of the file to be decrypted and the name of the file with the key. This method should produce a file containing the contents of the original file decrypted, and stored as decryptFileC.txt.

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Take a look at the following site

http://www.thefreecountry.com/sourcecode/encryption.shtml

Regards

Posted on Jun 16, 2009

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In network security + acronyms what is 3DES and definition


Triple Data Encryption Standard (DES) is a type of computerized cryptography where block cipher algorithms are applied three times to each data block. The key size is increased in Triple DES to ensure additional security through encryption capabilities. Each block contains 64 bits of data. Three keys are referred to as bundle keys with 56 bits per key. There are three keying options in data encryption standards:
  1. All keys being independent
  2. Key 1 and key 2 being independent keys
  3. All three keys being identical
Key option #3 is known as triple DES. The triple DES key length contains 168 bits but the key security falls to 112 bits.
What is Triple DES Definition from Techopedia

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When I start my cam model PK-752F it showRuntime error!Programe:C:/Programe Files/IM Magician/qsn.exethis application had requested the runtime to terminate in an unusual way.Plz contact the applications...


Contact the support team. You can uninstall the software and re install it to see if that helps. Otherwise the support people can get you running quickly.

Feb 21, 2014 | Computers & Internet

1 Answer

I want to set up password on my router


Step 1 Open a web browser and type the IP address of the DIR series router into the address bar (default is http://192.168.0.1). Press Enter

Step 2 The default username is admin (all lower case) and the default password is blank (nothing). Click on OK.

Step 3 Click on the Setup tab at the top and then click on Wireless Settings on the lefthand side.
Step 4 From the Wireless Security Mode dropdown menu, select WPA-Personal encryption.

Step 5 From the WPA Mode dropdown, Under WPA, select the form of WPA you would like to use.

Use WPA or WPA2 mode to achieve a balance of strong security and best compatibility. This mode uses WPA for legacy clients while maintaining higher security with stations that are WPA2 capable. Also the strongest cipher that the client supports will be used.

For best security, use WPA2 Only mode. This mode uses AES(CCMP) cipher and legacy stations are not allowed access with WPA security.

For maximum compatibility, use WPA Only. This mode uses TKIP cipher. Some gaming and legacy devices work only in this mode. To achieve better wireless performance use WPA2 Only security mode (or in other words AES cipher).


Step 6 In the Pre-Shared Key box, enter the desired Pre-shared key.

This is the "password" that allows communication between you're encrypted client (e.g. the PSP or your wireless computer) and the encrypted wireless signal coming from the router. This password must contain at least 8 characters, the characters can be anything you can create from your keyboard.

Step 7 Click on Save Settings

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1 Answer

I need to know my wep key or ssid codes, whats the difference? i need it to set up for my ps3 online


WEP (wired equivalent privacy)

The privacy protocol specified in IEEE 802.11 to provide wireless LAN users protection against casual eavesdropping. WEP refers to the intent to provide a privacy service to wireless LAN users similar to that provided by the physical security inherent in a wired LAN.


When WEP is active in a wireless LAN, each 802.11 packet is encrypted separately with an RC4 cipher stream generated by a 64-bit RC4 key. This key is composed of a 24-bit initialization vector (IV) and a 40-bit WEP key. The encrypted packet is generated with a bitwise exclusive OR (XOR) of the original packet and the RC4 stream. The IV is chosen by the sender and can be changed periodically so every packet won't be encrypted with the same cipher stream. The IV is sent in the clear with each packet. An additional 4-byte Integrity Check Value (ICV) is computed on the original packet and appended to the end. The ICV (be careful not to confuse this with the IV) is also encrypted with the RC4 cipher stream.

WEP has been widely criticized for a number of weaknesses:

Key management and key size
Key management is not specified in the WEP standard; without interoperable key management, keys will tend to be long-lived and of poor quality. Most wireless networks that use WEP have one single WEP key shared between every node on the network. Access points and client stations must be programmed with the same WEP key. Since synchronizing the change of keys is tedious and difficult, keys are seldom changed. Also, the 802.11 standard does not specify any WEP key sizes other than 40 bits. 

The IV is too small

WEP's IV size of 24 bits provides for 16,777,216 different RC4 cipher streams for a given WEP key, for any key size. Remember that the RC4 cipher stream is XOR-ed with the original packet to give the encrypted packet that is transmitted, and the IV is sent in the clear with each packet. The problem is IV reuse. If the RC4 cipher stream for a given IV is found, an attacker can decrypt subsequent packets that were encrypted with the same IV or can forge packets.

Weakness: The ICV algorithm is not appropriate
The WEP ICV is based on CRC-32, an algorithm for detecting noise and common errors in transmission. CRC-32 is an excellent checksum for detecting errors, but an awful choice for a cryptographic hash. Better-designed encryption systems use algorithms such as MD5 or SHA-1 for their ICVs. 

Authentication messages can be easily forged

SSID (Service Set IDentifier)
The SSID (Service Set IDentifier) is a token which identifies an 802.11 (Wi-Fi) network. 


The SSID is a secret key which is set by the network administrator.

You must know the SSID to join an 802.11 network. However, the SSID can be discovered by network sniffing. By default, the SSID is part of the packet header for every packet sent over the WLAN.
SSID Security Issues

The fact that the SSID is a secret key instead of a public key creates a key management problem for the network administrator. Every user of the network must configure the SSID into their system. If the network administrator seeks to lock a user out of the network, the administrator must change the SSID of the network, which will require reconfiguration of the SSID on every network node. Some 802.11 NICs allow you to configure several SSIDs at one time.
Default SSID's

Most 802.11 access point vendors allow the use of an SSID of "any" to enable an 802.11 NIC to connect to any 802.11 network. This is known to work with wireless equipment from Buffalo Technologies, Cisco, D-Link, Enterasys, Intermec, Lucent, and Proxim. Other default SSID's include "tsunami", "101", "RoamAbout Default Network Name", "Default SSID", and "Compaq".
Disabling SSID Broadcasting

Many Wireless Access Point (WAP) vendors have added a configuration option which lets you disable broadcasting of the SSID. This adds little security because it is only able to prevent the SSID from being broadcast with Probe Request and Beacon frames. The SSID must be broadcast with Probe Response frames. In addition, the wireless access cards will broadcast the SSID in their Association and Reassociation frames. Because of this, the SSID cannot be considered a valid security tool.
An SSID by any other name

The SSID is also referred to as the ESSID (Extended Service Set IDentifier).


Airsnort, Aircrack 2.1, Cain & Abel are some of the wireless packet sniffing tools which can decode the authorization key.

Dec 23, 2009 | D-Link ADSL2/2+ Modem/Wireless Router...

1 Answer

I hv a DIR-655 router & i've lost my manual. i want to secure my router and lock out others outside my residence. can you take me thru the steps?


Please visit http://support.dlink.com/faq/view.asp?prod_id=2484 for complete FAQ and screen shots.
Step 1
Open a web browser and type the IP address of the DIR series router into the address bar (default is http://192.168.0.1). Press Enter

Step 2 The default username is admin (all lower case) and the default password is blank (nothing). Click on OK.

Step 3 Click on the Setup tab at the top and then click on Wireless Settings on the lefthand side.

Step 4 From the Wireless Security Mode dropdown menu, select WPA-Personal encryption.

Step 5 From the WPA Mode dropdown, Under WPA, select the form of WPA you would like to use.

Use WPA or WPA2 mode to achieve a balance of strong security and best compatibility. This mode uses WPA for legacy clients while maintaining higher security with stations that are WPA2 capable. Also the strongest cipher that the client supports will be used.

For best security, use WPA2 Only mode. This mode uses AES(CCMP) cipher and legacy stations are not allowed access with WPA security.

For maximum compatibility, use WPA Only. This mode uses TKIP cipher. Some gaming and legacy devices work only in this mode. To achieve better wireless performance use WPA2 Only security mode (or in other words AES cipher).

Step 6 In the Pre-Shared Key box, enter the desired Pre-shared key.

This is the “password” that allows communication between you’re encrypted client (e.g. the PSP or your wireless computer) and the encrypted wireless signal coming from the router. This password must contain at least 8 characters, the characters can be anything you can create from your keyboard.

Step 7 Click on Save Settings to save your settings.

thanks Ranjit

Dec 09, 2009 | Computers & Internet

3 Answers

Wep key


it all depends. There is usually a way to set it if you connect directly to the router, with a cable, then open up the website 192.168.1.1
When you open that up, you will basically be viewing your router's web page, and in the wireless security settings you can manually set your WEP key. these settings are in different places for different routers, but that's the general idea.

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1 Answer

Hi there, i just had telstra install a Cisco 857w router. i am trying to setup the wrieless and am having no luck, i am not very computer literate so i may need to explained in very simple...


Need to setup the wireless on your 877W or 857w. use the following sample.. obviously update the SSID and wpa-psk key.
bridge irb
bridge 1 protocol ieee
bridge 1 route ip
interface Dot11Radio0
no ip address
bridge-group 1
no shut
!
broadcast-key change 60
!
!
encryption mode ciphers tkip
!
ssid MYSSID
max-associations 10
authentication open
authentication key-management wpa
no guest-mode
wpa-psk ascii mywpapskpwd
!
world-mode dot11d country AU outdoor
speed basic-1.0 basic-2.0 basic-5.5 basic-6.0 basic-9.0 basic-11.0 basic-12.0 basic-18.0 basic-24.0 basic-36.0 basic-48.0 basic-54.0
channel 2452
station-role root
no cdp enable
bridge-group 1
bridge-group 1 subscriber-loop-control
bridge-group 1 spanning-disabled
bridge-group 1 block-unknown-source
no bridge-group 1 source-learning
no bridge-group 1 unicast-flooding
interface Vlan1
no ip address
ip virtual-reassembly
ip tcp adjust-mss 1400
bridge-group 1
hold-queue 100 out
!
!
interface BVI1
ip address 10.0.0.3 255.255.255.0
ip nat inside
ip virtual-reassembly

Jun 09, 2009 | Computers & Internet

1 Answer

I have a visual basic program in which i have to display the record from access table by using connection of adodc.and then select record from datagrid will display in another form. plz reply as soon as...


hi,  you may visit this site www.kidwaresoftware.com/ and download all free visual basic source codes with tutorials..  One of the source code will solve your problem.    However their paid Visual basic source codes will most powerful.    As I am total deaf and no source to communicate others... I want to share the  payment source codes with tutorials from  www.kidwaresoftware.com/.  Are you ready... If you download the  source codes with tutorials (only Fee for it) I will share with you.    esakkisivaganesh@yahoo.co.in

Apr 08, 2009 | Microsoft Visual Basic Enterprise Edition...

1 Answer

Zebra QL 420+ wireless printer works only without cipher/TKIP


Hi
With Label Vista
  • Go to Printer Tab
  • Define the com Port settings (use serial or usb)
  • Go to Printer settings

in network tab :
  • Put your network configuration ( IP address or DHCP,submask, gateway; ESSID, port number .....)

In 802.1X WPA
  • Select WPA WPA2
  • Authentification PSK
  • Put the username and password in EAP section

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1 Answer

IE 7.0 Change it into High Encryption.


u can change the cipher strength by edit the properites of the IE7.0
or change in "services" which is in control panel -> Administrative Tools

Mar 13, 2008 | Microsoft Office Outlook 2003 for PC

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