s outlined above are numerous and interlinked. There is no quick fix or one magic solution that solves all of these problems. Trust and security can only be guaranteed through a range of measures. In the real world, the main ways of ensuring confidence in the transaction process are;
Use of a Notary Public/Solicitor
Power of attorney
Identification (e.g., driver's licence/passport)
Certified post
Return receipt
In the virtual world, a range of measures have been developed to address these same concerns:
Secure socket layer (SSL) – the padlock symbol on secure internet pages.
Encryption
Digital certificate
Legal digital signature
Vetting
What is Encryption?
Cryptography is essential in preserving the secret nature of the data transfer. For example if “Hello Class” is the message, then you can invent a rule that every letter is replaced by a letter three along in the alphabet. Thus the message becomes “Khoor Fodvv.” This only offers basic protection. A much more complicated mathematical code is required. An example of which is the German Enigma machine of World War II. It took tens of thousands of man hours for the British to crack the code.
Encryption involves scrambling a transaction in readable form (plaintext) into unreadable form (cyphertext) by use of an encryptio英语论文网 【http://www.51lunwen.org】n algorithm and an encryption key.
Cryptography subdivides into symmetric [Shared Key/Private Key] and asymmetric [Two Key/Public] cryptography.
Symmetric Cryptography
Symmetric cryptography is a private key system where the information is encrypted and decrypted using the same key held by both sides. This is clearly impractical for large scale e-commerce. Private key cryptography relies upon a great deal of trust between the two parties. The main disadvantage of this system is the difficulty in ensuring the key is kept confidential, given that the key has to be communicated, in the first instance, from sender to receiver. The technology used to keep private keys confidential depends in part on the application of mathematical principles and relies on the difficulty of factoring large numbers into their prime number components. Unfortunately it may be that these factoring problems can in fact be solved using powerful computer systems.
Asymmetric Cryptography
Asymmetric cryptography is essentially public key cryptography. This system uses a public key and a private key. Two keys are in use, one for the sender and another for the receiver. One key "locks" a document, and a separate key "unlocks.” The private key is kept by the owner and locks the document. The public key unlocks the data. However, the 2 keys are not independent. They can be thought of as a unique t
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