Compression is the reduction in size of data without losing information.

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Is compressing data prior to encryption necessary to reduce plaintext redundancy?

As explained in William Stallings' Book, in PGP encryption is done after compression, since it reduces redundancy. I couldn't relate encryption strength with redundancy. Could anyone explain more on ...
6
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2answers
1k views

How much can we compress RSA public keys?

I am wondering to what degree we can define an RSA variant, with a security argument that it is as safe as regular RSA with a given modulus size $m$ (e.g. $m=2048$), in which the public key has a ...
3
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1answer
90 views

Is it ever unsafe to compress an EC point?

I am working with a library that outputs EC points in uncompressed form. To save space, I'm considering modifying said library to use compressed EC points. Assuming that I keep track of the sign bit ...
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2answers
232 views

How does compression before encryption leak info about the input?

Apparently current best practices recommend that you do not compress before you encrypt. For example in this blog entry (*): http://sockpuppet.org/blog/2013/07/22/applied-practical-cryptography/ It ...
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3answers
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Point decompression on an elliptic curve

I'm programming an elliptic curve cryptosystem and I'm having difficulty with decompressing points. The following information is from my project specification as to my understanding: Given a point ...