A digital signature is a mechanism that is used to verify that a particular digital document, message or transaction is authentic.

The security technologies in E-Commerce transactions are roughly classified into
(i) Encryption technology
(ii)  Authentication technology
(iii) Authentication protocols

Non-repudiation: Repudiation refers to any act of relinquishing responsibility for a message. Non-repudiation ensures that the signer who digitally signed the document cannot deny having signed it. The digitally signed documents strengthen its recipient integrity claims. Therefore, the recipient can strongly insist on the signature of the sender so as not to be easily denied at a later time.

Typopiracy is a variant of Cyber Squatting. Some fake websites try to take advantage of users common typographical errors in typing a website address and direct users to a different website. Such people try to take advantage of some popular websites to generate accidental traffic for their websites. e.g. www.goggle.com, www.facebook.com

Information leakage: The leakage of trade secrets in E-commerce mainly includes two aspects: (a) the content of the transaction between the vendor and customer is stolen by the third party; (b) the documents provided by the merchant to the customer or vice versa are illegally used by the another. This intercepting and stealing of Online documents is called information leakage.