Abstract: Provided is a composition for surface treatment of a steel sheet, the composition having excellent resistance to an acid, such as sulfuric acid, and to a coated steel sheet to which the composition for surface treatment is applied, wherein the composition for surface treatment comprises 30-50% wt % of colloidal silica containing 5-20 nm-sized silica, 40-60% wt % of silane containing three or more alkoxy groups, 5-15 wt % of an acrylate-based organic monomer, 0.01-1 wt % of an acid, and 1-15 wt % of a solvent.

Abstract: The present invention relates to a device and method that enable a security key to be shared using security key exchange between two terminals, and a system that supports the same. To achieve the above, an in-house generated public key is divided into two, said two public keys that have been divided are delivered to counterpart devices via different pathways, and the two public keys delivered from counterpart devices are used to predict the public key of the counterpart device. In addition, said predicted public key is verified, and said verified public key is used to form a master key. Subsequently, said generated master key is verified, and said master key that has been verified is used to exchange data with the counterpart device.

Abstract: The present invention relates to a device and method that enable a security key to be shared using security key exchange between two terminals, and a system that supports the same. To achieve the above, an in-house generated public key is divided into two, said two public keys that have been divided are delivered to counterpart devices via different pathways, and the two public keys delivered from counterpart devices are used to predict the public key of the counterpart device. In addition, said predicted public key is verified, and said verified public key is used to form a master key. Subsequently, said generated master key is verified, and said master key that has been verified is used to exchange data with the counterpart device.

Abstract: Provided are a system and method for allocating an Internet protocol version 4 (IPv4) address through authentication of a dual stack transition mechanism (DSTM) node in a DSTM communication network, DSTM being an IPv4/IPv6 address translation mechanism. The system and method perform authentication when an IPv4 address is allocated between a DSTM node and the DSTM server in the DSTM communication network. According to the system and method, when the DSTM node requests IPv4 address allocation, the DSTM server authenticates the DSTM node, and then allocates an IPv4 address. Therefore, it is possible to solve a problem of exhaustion of an IPv4 address pool of the DSTM server by a denial of service (DoS) attack, as well as potentially solve a security problem of an IPv4/IPv6 translation process.