Implementation Of IDEA Encryption Algorithm Based On MCS51

Public Switch Telephone Network is one of mature networks.It can not only provide telephone service but also provide data communicating service. The service is useful especially in some special area, such as remote mountain area. Public switch telephone network communicats data through plain, so the information is more possible to be obtain by unlawful means in the communicating procedure. Therefore this mdel is not suitable for high safety requesting communication. Under such entertainment, a safe way should be created. What shold to do is to encrypt before communication. At present, the encryption technology is maturer and maturer, and new algorithm is created every day. The encryption is divided to hardware and software encryption. In nowdays, most of the encryption algorithm is operated basing on software. Compared with basing on software, basing on hardware needs system design and it is not as convenient as basing on software. However, basing on hardware has its obvious advantage that it makes the encryption algorithm separate from the host while make the host avoid spending time on the procedure of encryption and decryption. Thus the host can do better to deal its work. This subject choices IDEA as its encryption algorithm.IDEA is one kind of symmetry encryption key algorithms. It is easy to be operated basing on both software and hardware with high secretivity and quick procedure. Some essay points that there is weak-encryption key in IDEA. So the improvement was operated in tlhe procedure of choosing the sub-encryption key. It is easy to complete through lots of encryption key room application.