Why BitLocker does not use RSA





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If I do not understand wrong from this post and Wikipedia page of the BitLocker and TPM, by default, BitLocker uses symmetric cryptography like AES. However, TPM is capable of performing RSA encryption.
Given that, the RSA key is stored in the TPM, why BitLocker does not use the asymmetric encryption (i.e., RSA)? By using such encryption technique, we might be able to defend against the cold boot attack or sniffing on LPC bus.










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    If I do not understand wrong from this post and Wikipedia page of the BitLocker and TPM, by default, BitLocker uses symmetric cryptography like AES. However, TPM is capable of performing RSA encryption.
    Given that, the RSA key is stored in the TPM, why BitLocker does not use the asymmetric encryption (i.e., RSA)? By using such encryption technique, we might be able to defend against the cold boot attack or sniffing on LPC bus.










    share|improve this question







    New contributor




    user3862410 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      If I do not understand wrong from this post and Wikipedia page of the BitLocker and TPM, by default, BitLocker uses symmetric cryptography like AES. However, TPM is capable of performing RSA encryption.
      Given that, the RSA key is stored in the TPM, why BitLocker does not use the asymmetric encryption (i.e., RSA)? By using such encryption technique, we might be able to defend against the cold boot attack or sniffing on LPC bus.










      share|improve this question







      New contributor




      user3862410 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      If I do not understand wrong from this post and Wikipedia page of the BitLocker and TPM, by default, BitLocker uses symmetric cryptography like AES. However, TPM is capable of performing RSA encryption.
      Given that, the RSA key is stored in the TPM, why BitLocker does not use the asymmetric encryption (i.e., RSA)? By using such encryption technique, we might be able to defend against the cold boot attack or sniffing on LPC bus.







      aes rsa tpm bitlocker cold-boot-attack






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          Asymmetric encryption like RSA is limited in that you can only use it to encrypt data the size of the key. With a 2048 bit key, you can only encrypt 2048 bits of information. For this reason RSA is unsuitable for bulk encryption like disks - and even for small files like email messages.



          This is why almost all uses of asymmetric encryption involve "hybrid encryption". RSA is used to encrypt the key for a symmetric algorithm like AES, and AES is used to encrypt the bulk data. PGP is an example of a hybrid encryption application.






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            Asymmetric encryption like RSA is limited in that you can only use it to encrypt data the size of the key. With a 2048 bit key, you can only encrypt 2048 bits of information. For this reason RSA is unsuitable for bulk encryption like disks - and even for small files like email messages.



            This is why almost all uses of asymmetric encryption involve "hybrid encryption". RSA is used to encrypt the key for a symmetric algorithm like AES, and AES is used to encrypt the bulk data. PGP is an example of a hybrid encryption application.






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              Asymmetric encryption like RSA is limited in that you can only use it to encrypt data the size of the key. With a 2048 bit key, you can only encrypt 2048 bits of information. For this reason RSA is unsuitable for bulk encryption like disks - and even for small files like email messages.



              This is why almost all uses of asymmetric encryption involve "hybrid encryption". RSA is used to encrypt the key for a symmetric algorithm like AES, and AES is used to encrypt the bulk data. PGP is an example of a hybrid encryption application.






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                2







                Asymmetric encryption like RSA is limited in that you can only use it to encrypt data the size of the key. With a 2048 bit key, you can only encrypt 2048 bits of information. For this reason RSA is unsuitable for bulk encryption like disks - and even for small files like email messages.



                This is why almost all uses of asymmetric encryption involve "hybrid encryption". RSA is used to encrypt the key for a symmetric algorithm like AES, and AES is used to encrypt the bulk data. PGP is an example of a hybrid encryption application.






                share|improve this answer













                Asymmetric encryption like RSA is limited in that you can only use it to encrypt data the size of the key. With a 2048 bit key, you can only encrypt 2048 bits of information. For this reason RSA is unsuitable for bulk encryption like disks - and even for small files like email messages.



                This is why almost all uses of asymmetric encryption involve "hybrid encryption". RSA is used to encrypt the key for a symmetric algorithm like AES, and AES is used to encrypt the bulk data. PGP is an example of a hybrid encryption application.







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                answered 2 hours ago









                gowenfawrgowenfawr

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