5. Index

6. Definition E-commerce : is the buying and selling of goods and services on the Internet, especially the World Wide Web. E-commerce has many types such as: 1 - B2B (Business-to-Business). Companies doing business with each other such as manufacturers selling to distributors. 2 - B2C (Business-to-Consumer). Businesses selling to the general public typically through catalogs utilizing shopping cart software. 3-C2B (Consumer-to-Business). A consumer posts his project with a set budget online and within hours companies review the consumer's requirements and bid on the project.

7. 4- C2C (Consumer-to-Consumer). There are many sites offering free classifieds, auctions, and forums where individuals can buy and sell thanks to online payment systems like PayPal and eBay's auction. Definition E-government : is the use of information and communication technologies (ICTs) to improve the activities of public sector organizations E-government has many types such as: 1- G2G (Government-to-Government) 2- G2E (Government-to-Employee) 3- G2B (Government-to-Business) 4- B2G (Business-to-Government) 5- G2C (Government-to-Citizen) 6- C2G (Citizen-to-Government)

8. the attacker : As mentioned, the vulnerability of a system exists at the entry and exit points within the system. This figure shows an e-Commerce system with several points that the attacker can target: 1- Shopper 2- Shopper' computer 3- Network connection between shopper and Web site's server 4- Web site's server 5- Software vendor

10. Defenses : Despite the existence of hackers and crackers, e-Commerce remains a safe and secure activity. The resources available to large companies involved in e-Commerce are enormous. These companies will pursue every legal route to protect their customers. This figure shows a high-level illustration of defenses available against attacks.

12. the Secure Sockets Layer (SSL) protocol. Originally developed by Netscape, SSL has been universally accepted on the World Wide Web for authenticated and encrypted communication between clients and servers. SSL is the important part in security. Secure Socket Layer (SSL) have two keys that are public key,private key Public key encryptes the data between browser and server. private key translate the encrypted data to original data. In example about SSl in different browsers:

13. Reliability E-commerce Reliability depends on security in websites when 1- website is protected and it’s security is very hard and stonge so the human will depend on this website. 2- website is weak in security so the human would not depend on this website.

15. Reliability E-commerce Reliability: depends on security in websites when 1- website is protected and it’s security is very hard and stong so the human will depend on this website. 2- website is weak in security so the human would not depend on this website.