# How can I convert lwe (TFHE) ciphertexts to RLWE (CKKS or BFV) ciphertexts?

**URL:** <https://openfhe.discourse.group/t/how-can-i-convert-lwe-tfhe-ciphertexts-to-rlwe-ckks-or-bfv-ciphertexts/696>\
**Category:** FHE Questions\
**Created:** [July 13, 2023, 9:56am UTC](https://openfhe.discourse.group/t/how-can-i-convert-lwe-tfhe-ciphertexts-to-rlwe-ckks-or-bfv-ciphertexts/696 "2023-07-13T09:56:28Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Jianan\_Mu](https://avatars.discourse-cdn.com/v4/letter/j/a3d4f5/32.png) [@Jianan\_Mu](https://openfhe.discourse.group/u/Jianan_Mu)\
**Post date:** [July 13, 2023, 9:56am UTC](https://openfhe.discourse.group/t/how-can-i-convert-lwe-tfhe-ciphertexts-to-rlwe-ckks-or-bfv-ciphertexts/696/1 "2023-07-13T09:56:28Z")

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Hello!  
I really wonder how can I convert lwe (TFHE) ciphertexts to RLWE (CKKS or BFV) ciphertexts? Is there some implementations already?  
I want to know the efficiency of this procedure~ ~I want to design a comparison and multiplication operation based on this.  
And by now, which solution has the best performance? Is it the solution in the paper of Efficient Homomorphic Conversion Between (Ring) LWE Ciphertexts?  
I am looking forward to your response!

Best regards

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**Author:** ![iquah](https://yyz1.discourse-cdn.com/flex031/user_avatar/openfhe.discourse.group/iquah/32/8_2.png) [@iquah](https://openfhe.discourse.group/u/iquah)\
**Post date:** [July 13, 2023, 12:58pm UTC](https://openfhe.discourse.group/t/how-can-i-convert-lwe-tfhe-ciphertexts-to-rlwe-ckks-or-bfv-ciphertexts/696/2 "2023-07-13T12:58:28Z")

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We don’t have any capability in place for scheme switching just yet. It should be coming out end of July

> [@Question for Coefficient Packing for CKKS and File Not Found Error in Scheme-Switching branch](https://openfhe.discourse.group/t/question-for-coefficient-packing-for-ckks-and-file-not-found-error-in-scheme-switching-branch/681/4):
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> Hi @swanhong CoefPackedPlaintext is currently supported only for BGV and BFV (for the case where numbers modulo t are encoded). We have not seen yet a need for a coefficient encoding in CKKS (as a user feature). All use cases we have seen typically work with the CKKSPackedEncoding encoding. The coefficient encoding internally comes up in CKKS bootstrapping or scheme switching from CKKS ↔ FHEW, but these are handled automatically by the library using methods like SlotsToCoef (still operating on …

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**Author:** ![Jianan\_Mu](https://avatars.discourse-cdn.com/v4/letter/j/a3d4f5/32.png) [@Jianan\_Mu](https://openfhe.discourse.group/u/Jianan_Mu)\
**Post date:** [July 14, 2023, 6:23am UTC](https://openfhe.discourse.group/t/how-can-i-convert-lwe-tfhe-ciphertexts-to-rlwe-ckks-or-bfv-ciphertexts/696/3 "2023-07-14T06:23:16Z")

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Okay, thanks for your reply. I will wait for the new version and have a try at that time!