SecurityAlgorithmSuite Basic256

Question

User1992544565 posted

Dear all,

I'd like to know what's the default operation mode (e.g.: CBC, GCM, CTR?) of the AES implementation of Basic256 as described in:

https://msdn.microsoft.com/en-us/library/system.servicemodel.security.securityalgorithmsuite.basic256(v=vs.110).aspx

Could you please provide me the details?

Thanks in advance.

Answer 1

User36583972 posted

Hi barbaravieira,

As far as I know, there are many block modes defined in the cipher realm. Different block modes have different characteristics. For example, the CRT mode only needs encryption logic, so it is suitable for low cost hardware implementations. As for CFB, OFB modes, there is an extra parameter: 'feedback size'. You can treat it as the result size of each AES block process.

The following links for your reference.

How to choose an AES encryption mode (CBC ECB CTR OCB CFB):

http://stackoverflow.com/questions/1220751/how-to-choose-an-aes-encryption-mode-cbc-ecb-ctr-ocb-cfb

Block cipher mode of operation:

https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation

AES Encryption and Decryption (ECB, CTR, CBC, CFB, OFB, OMAC, CCM, GCM, XTS):

http://www.xilinx.com/products/intellectual-property/1-8dyf-2719.html

Best Regards,

Yohann Lu

Answer 2

User1992544565 posted

Hi Yohan, 

Thanks for your answer, but I think you misunderstood my question.

I know the existence of different modes of operation for block cipher, but I'm not asking that.

If I'm not mistaken Basic256 in .Net corresponds to AES, but the default mode of operation used by Basic256 implementation is not know and I couldn't find any information on that.

The question is: is Basic256 just AES or is AES plus a mode of operation? If implemented using mode of operation, which mode is that?

Thanks in advance.

Best regards,

Bárbara Vieira