Abstract: The method comprises registering at least one of an internet protocol (IP) address and a media access control (MAC) address of the security devices, generating a plurality of public key and private key pairs, encrypting and storing private keys comprised in the plurality of public key and private key pairs using a master key provided from a master key management unit, selecting any one of a plurality of public key and private key pairs when the access of the security device is approved and providing a certificate comprising the selected public key to the security device, receiving a symmetric key encrypted with the public key of the certificate from the security device, and decrypting the private key using the master key provided from the master key management unit.

Abstract: Provided is a security authentication method of a network video recorder (NVR) including assigning a terminal unique index to each of pseudo-random functions included in a pseudo-random function set using terminal information; transmitting a session key having a predetermined expiry time and the pseudo-random function set with the assigned terminal unique index to a terminal; calculating a first terminal unique index for authenticating a first message using a predetermined bitstream of the first message received from the terminal; selecting a first pseudo-random function for authenticating the first message using the calculated first terminal unique index; generating a first independent private key of the terminal for authenticating the first message by inputting the session key and a MAC address of the terminal to the first pseudo-random function; and generating a message authentication code for the first message using the first independent private key and authenticating the first message.

Abstract: Disclosed is a method for maintaining security of video data of a decryption server. The method comprises registering at least one of an internet protocol (IP) address and a media access control (MAC) address of the security devices, generating a plurality of public key and private key pairs, encrypting and storing private keys comprised in the plurality of public key and private key pairs using a master key provided from a master key management unit, selecting any one of a plurality of public key and private key pairs when the access of the security device is approved and providing a certificate comprising the selected public key to the security device, receiving a symmetric key encrypted with the public key of the certificate from the security device, and decrypting the private key using the master key provided from the master key management unit.

Abstract: Disclosed is a method for maintaining security of video data of a security device. The method comprises transmitting an access request to decryption server, receiving certificate information comprising a public key arbitrarily selected by the decryption server when the access request is approved, generating a symmetric key for encrypting video data, encrypting the symmetric key using the public key, and transmitting the encrypted symmetric key to the decryption server.

Abstract: Provided is a security authentication method of a network video recorder (NVR) including assigning a terminal unique index to each of pseudo-random functions included in a pseudo-random function set using terminal information; transmitting a session key having a predetermined expiry time and the pseudo-random function set with the assigned terminal unique index to a terminal; calculating a first terminal unique index for authenticating a first message using a predetermined bitstream of the first message received from the terminal; selecting a first pseudo-random function for authenticating the first message using the calculated first terminal unique index; generating a first independent private key of the terminal for authenticating the first message by inputting the session key and a MAC address of the terminal to the first pseudo-random function; and generating a message authentication code for the first message using the first independent private key and authenticating the first message.

Abstract: A method for providing a cyber security simulation training content by a server, includes: receiving from a client terminal, a connection link call request of a virtual machine (VM) corresponding to at least one cyber security simulation training content; selecting, by the virtualization connection unit, VM information corresponding to the connection link call request of the VM from a database (DB) of the WAS; transmitting the VM information selected from the DB to a daemon module of the WAS; requesting a first VM link from a virtualization management unit of the virtualization element using the VM information; generating the first VM link by the virtualization management unit and transmitting the generated first VM link to the daemon module; obtaining a second VM link from the DB using the first VM link; and providing information on the second VM link to the client terminal.