Nowadays, people commonly communicate via digital data. The commercial affairs, public affairs or private affairs are preceded by means of e-mail anyhow. However, some important and confidential data, which are stored in a storage memory without protection, could be stolen away by unauthorized users easily, wherein the important and confidential data could not be protected in motion.
For preventing from the above situations, there are a lot of mechanisms disclosed according to data encryption standards, wherein the data encryption is the process of protecting data from unauthorized access, use, disclosure, destruction, modification, or disruption in motion of transmission or storage. Usually, the encryption process transforms the comprehensible data into the incomprehensible data according to a specific computer algorithm that rearrange the data bits in digital signals; and the decryption process, which is the reverse of the encryption process, transforms the incomprehensible data back to the original comprehensible data according to a reverse algorithm. In practice, data is transformed into the incomprehensible data, and then the incomprehensible data are transmitted via the network (such as Internet or Intranet), or stored in the memory. Furthermore, when the incomprehensible data are received or researched by the user with access authorization, the user executes the decryption process to decrypt the encrypted data for utilizing the original data.
Following the development of electronic and communication technologies, the electronic transactions are able to provide facilities of saving/drawing of bank account, going shopping, paying tax, and so on, and thereby providing convenience of life and further saving time. However, there could be a latent problem of network security for improving the convenience. As we know, the communication of Internet and Intranet could be executed according to several different standards, such as TCP/IP, UDP, FTP, RPC, RIC, HTTP, SMTP, IEEE802.3, and so on. Congenitally, those several communication protocols don't introduce any encryption schemes into the network. Therefore, the unauthorized users could easily get communicating data in the public network and then rearrange data via applicable combinations, thereby achieving the purpose of stealing data. Obviously, when the important data are transmitted via the network without introducing the complete encryption schemes or defining related secure communication protocols in several levels of network, the public network won't provide transmitted data with secure and powerful protections.
Moreover, wireless mobile communication has become a mainstream of modern communication services. Comparatively, it is not easy to setup substantive constructions of wire phone communication, leased line communication or optical fiber communication. Therefore, wireless mobile communication should take them over. Meanwhile, IEEE (Institute of Electrical and Electronic Engineers) defines IEEE 802.11 communication protocol for Wireless Local Area Networks (WLAN). For instance, SSL (Secure Sockets Layer), originated by Netscape Development Corporation (disclosed in U.S. Pat. No. 5,657,390), is a commonly used protocol. The SSL protocol is designed to establish a secure connection by means of RSA Public Key cryptography between a client and a server communicating over an insecure channel. Presently, the SSL has been introduced into the great part of network servers and browsers. Furthermore, Secure Electronic Transaction (SET) is a system for ensuring the security of financial transactions on the electronic commerce. It is supported initially by VISA®, MasterCard®, IBM®, Microsoft®, Netscape®, GTE®, VeriSign®, SAIC®, Terisa® and others. With SET, a user is given an electronic wallet (digital certificate) and a transaction is conducted and verified using a combination of digital certificates and digital signatures via RSA Public Key cryptography among the purchaser, a merchant, and the purchaser's bank in a way that ensures privacy and confidentiality. Those security protocols commonly used in Wireless Local Area Networks (WLAN) are derived from a predecessor of wireless modem; wherein the communication is limited in end-to-end; and the wireless transmission medium is introduced by means of radio frequency (RF). Thus, the data of system could be eavesdropped, stolen, or destroyed easily by illegal users. Therefore, the security of network transmission should be attached great importance to.
Accordingly, the prior electronic commerce fails to provide a complete security system; and the wireless communication is limited in end-to-end according to the prior art. Therefore, in practice, the prior art could not provide a network communication system with entire security. Hence, it needs to provide a network security system and a protecting method applied in network data transmission, wherein electronic commerce and business transaction are dealt anytime in the construction, to rectify those drawbacks of the prior art and solve the above problems.