Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
mạng lưới tư nhân đã được sử dụng bởi các tổ chức để giao tiếp với các trang web từ xa và với các tổ chức khác. mạng riêng được tạo thành đường dây thuê bao từ các công ty điện thoại khác nhau và các ISP. Những dòng điểm tới điểm và các bit mà đi du lịch vào những dòng này được tách biệt từ giao thông khác bởi vì các đường dây thuê bao tạo ra một mạch thực sự giữa hai trang web | CHAPTER 10 Virtual Private Networks Copyright 2001 The McGraw-Hill Companies Inc. Click Here for Terms of Use. 167 168 Network Security A Beginner s Guide Private networks have been used by organizations to communicate with remote sites and with other organizations. Private networks are made up of lines leased from the various phone companies and ISPs. The lines are point to point and the bits that travel on these lines are segregated from other traffic because the leased lines create a real circuit between the two sites. There are many benefits to private networks Information is kept within the fold. Remote sites can exchange information instantaneously. Remote users do not feel so isolated. Unfortunately there is also a big disadvantage cost. Private networks cost a lot of money. Using slower lines can save some money but then the remote users start to notice the lack of speed and some of the advantages begin to evaporate. With the increasing use of the Internet many organizations have moved to Virtual Private Networks VPN . VPNs offer organizations many of the advantages of private networks with a lower cost. However VPNs introduce a whole new set of issues and risks for an organization. Properly architected and implemented VPNs can be advantageous to the organization. Poorly architected and implemented all the information that passes across the VPN might as well be posted on the Internet. DEFINING VIRTUAL PRIVATE NETWORKS So we are going to send sensitive organization information across the Internet in such a way as to reduce the need for leased lines and still maintain the confidentiality of the traffic. How do we separate our traffic from everyone else s The short answer is that we use encryption. All kinds of traffic flow across the Internet. Much of that traffic is sent in the clear so that anyone watching the traffic can see exactly what is going by. This is true for most mail and Web traffic as well as telnet and FTP sessions. Secure Shell SSH and .
