In some embodiments, the recovery escrow service stores the recovery private key, and instructions to publish the recovery private key are provided by a third party. In some embodiments, a status report of the at least one first computing device in a public repository is periodically published by the third party. In some embodiments, the at least one second computing device includes a mobile computing device. In some embodiments, the at least one second computing device is connected to the computer network, and a transaction is added to a ledger of the computer network, in accordance with the received signed at least a portion of the cryptographic key.

There is thus provided, in accordance with some embodiments of the invention, a system for verification that a cryptographic key associated with a blockchain based computer network can be decrypted, the system including: at least one first computing device, configured to: encrypt at least a portion of a cryptographic key of the computer network with a recovery public key, wherein the encryption is carried out using an homomorphically additive encryption scheme, at least one second computing device, in communication with the at least one first computing device, and configured to: receive the encrypted at least a portion of the cryptographic key from the at least one first computing device, retrieve a recovery public key from the at least one first computing device, and verify that the encrypted at least a portion of the cryptographic key is compatible to be decrypted by the recovery private key, based on the retrieved recovery public key and the corresponding public key of the at least a portion of the cryptographic key.