Network Security refers to the security of operating systems and servers. Hackers can gain portions of control over your operating systems or servers by exploring flaws in operating system and server software. Software vendors usually respond to security holes quickly in patches.
Firewall software restricts access by network protocols and IP addresses. For Web applications, the typical firewall configuration is to place public Web server outside the firewall and rest of servers (such as database, email server, FTP and etc) inside the firewall, and configure the firewall to allow only HTTP access for incoming requests.
Virtual Private Network (VPN)
For geographically dispersed organizations who don't want use expensive private networks, they can use encryption technology and software to create a Virtual Private Network (VPN). Network traffic is encrypted while traveling through the Internet.
The physical network that carries network traffic is not part of the Internet. This option offers additional security with extra cost, of course.
Application Security for Ecommerce Systems
Physical Security for Ecommerce Systems
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