10 questions linked to/from Purpose of DES parity bits
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### 128 bit 3DES Key and AES Key: what's the difference?

Apologies if this is really basic but I couldn't find the answer to this. I have heard some Info Sec colleagues talking about creating an AES key in preference to a DES or 3DES key but I don't know ...
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### Converting normal alphabets to 64 bit plain text

How can I convert a normal alphabetical text (say hi) to a 64 bit or 128 bit binary digit input for DES?
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### Multi Factor Encryption?

I got an alert last night to the keywords above and was curious, so took a look at the tor site flagged which is the following one: http://nsrz5iogimqwgeax3clpp6hvfy6viom2woy7dghgxes4sqk63r7svoqd....
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### What is the keyspace of 2-key 3DES?

I am assuming that 2-key 3DES is equivalent to 2DES. I know the key size is 2x56 = 112 bits. Is this key size the same as the keyspace? e.g. Would the keyspace be 112 bits ($2^{112}$)?
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### How was PC2 designed?

I am trying to understand DES. Can anyone explain the table given in one of the answer DES Key Schedule Algorithm. My question is from where the first entry of Ks comes from. i.e ...
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### Parity checking on DES key if using ASCII chars

This is my first question here, so if I ask it to the wrong group or otherwise infringing the (written or unwritten) rules of the community, please bear with me. My problem is this: In an exercise in ...
255 views

### How to find a triple of keys that maps plaintext to given cipherext using EDE

What is a practical method for for finding a triple of keys that maps a given plaintext to a given ciphertext using EDE? I think this requires something similar to a man-in-the-middle attack...
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### aside from DES has the NSA ever strengthened algorithms?

When DES was originally developed, the NSA changed the s-boxes. For decades people thought that their changes introduced a backdoor but then it was discovered that their changes actually strengthened ...