ITEE ITEE-1 | Page 297

Reference One-way hash function A “one-way hash function” is a function that converts an entered value into another value in such a way that it is not possible to derive the entered value through reverse conversion of the converted value. Reference One-time password A “one-time password” can be used for one login session only, after which it is discarded. The password is generated using a piece of hardware called a password generator. The advantage of a one-time password is that security is not compromised if the one-time password is leaked, as the password is changed for each login. ●Response by security administrator A security administrator, regardless of position, must not know the passwords of users, due to the risk of password leakage. If a password is forgotten by a user, the old password should be initialized and rendered unusable, and the user should personally reset the password. The security administrator should not be the one to set a new password. It is also necessary to take measures to ensure that the contents of password files used for password registration cannot be immediately deciphered in case the password files are stolen, and to prevent malicious use of the passwords. One method is to encrypt the passwords in advance. A “one-way hash function” is often used to prevent the deciphering of encrypted passwords. ABC Match XYZ Person A Password file Person A Conversion using hash function Third party Reference SSL “SSL” is a protocol developed by Netscape Corporation to provide communications security for the transport layer of TCP/IP. Specifically, SSL is used to encrypt the sending and receiving of information between an Internet server and a Web browser so that a third party cannot use the information for malicious purposes. Abbreviation for “Secure Sockets Layer.” 291 (3)Use of encryption “Encryption” is the process of converting information into a format that cannot be leaked to a third party when exchanging data over the Internet. Using encryption during communications can prevent the theft of information. (4)Setting a firewall A “firewall” is a system that prevents unauthorized intrusion from the Internet. It functions as the entry and exit point between a company network and the Internet in order to monitor communications and block unauthorized communications. The most basic function of a firewall is “packet filtering,” which searches for information such as the IP address of packets, as well as TCP port numbers and UDP port numbers. Only packets that contain a previously registered and permitted IP address, TCP port number, or UDP number are allowed to pass through the firewall. This prevents the intrusion of packets that do not have permission.