Efficiency/Simplification
Related to the evidential reason above. The transaction that is the subject of the signed document is to be presumed legitimate. Certain documents, such as negotiable instruments, if formally correct and complete can change hands easily, quickly and efficiently.

Deterrence
The need for signatures will discourage certain transactions from being entered into, that is, a minimum threshold for certain contracts will be required. The need for certain formalities to be complied with offers protection for both parties to the transaction and prevents unfair transactions or transactions with a high risk of non-compliance from being finalised.

Identity
To ensure that each party to the contract is informed as to the true identity of the other transacting party.

Confidentiality/Data Protection

The bargain concluded between the parties may include confidential information, price sensitive information or indeed privacy may simply be desired. As a record of the intentions of the parties, the written document may be retained by the legal advisers or other professional advisers to the parties. The personal nature of the information contained in the document will ensure that both sides adequately protect the security of 英语论文网 【http://www.51lunwen.org】that document. Confidentiality can be achieved through use of encryption techniques.
It could be argued that all of these issues are actually part of the broader issue of Contract Enforceability. Contract Enforceability is achieved by use of digital signatures, hash totals and transaction certificates.
 
E-COMMERCE
In addition to the purposes discussed above, e-commerce faces additional problems in ensuring trust and confidence.  Thus, e-commerce rules must satisfy the objectives below. 

Data Integrity
This principle subdivides into two categories, Interception and Tampering.

Interception
Ensuring that the documentation has been sent and received without third party intervention. Data Integrity is achieved by use of computer-generated hash totals.

Tampering
Ensuring that third parties have not intercepted the communication/data transfer and have amended such information.

Deception
Fraud, identity theft and theft are ubiquitous problems in cyberspace.
Access

Digital data must be kept secure, both from internal and external users who are not authorised. Access is controlled by use of firewalls, proxy servers and bio-metrics.

How are these objectives secured in the real world and in cyberspace?
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