tailieunhanh - Bảo mật hệ thống mạng part 28

Quản lý VPN User Quản trị mạng riêng ảo sử dụng chủ yếu là một vấn đề quản lý người dùng và hệ thống máy tính người dùng. Thích hợp với người sử dụng quản lý thủ tục nên được tại chỗ và sau khi ly thân của nhân viên. Rõ ràng, các phiên bản phần mềm VPN và cấu hình thích hợp phải được nạp vào máy tính người dùng. Nếu các máy tính là sở hữu của tổ chức, điều này trở thành một phần của phần mềm tải tiêu chuẩn cho máy tính | 173 Chapter 10 Virtual Private Networks For example if Organization A is a consulting company with employees working at Organization B A might like its employees to be able to connect back for mail and file access. However if they are working from computers attached to B s internal network and B uses dynamic NAT to hide the addresses of internal systems this may not be possible. If your organization chooses to use its VPN in this matter you should check the capabilities of the VPN software in this regard. Managing User VPNs Managing user VPNs is primarily an issue of managing the users and user computer systems. Appropriate user-management procedures should be in place and followed during employee separation. Obviously the proper VPN software versions and configurations must be loaded on user computers. If the computers are owned by the organization this becomes part of the standard software load for the computer. If the organization allows employees to use the VPN from their home computers the organization will need to increase overall support to these users as different computers and ISPs may require different configurations. One key aspect of the user VPN that should not be forgotten is the use of a good anti-virus software package on the user s computer. This software package should have its signatures updated on a regular basis at least monthly to guard against viruses and Trojan Horse programs being loaded on the user s computer. SITE VPNS Site VPNs are used by organizations to connect remote sites without the need for expensive leased lines or to connect two different organizations that wish to communicate for some business purpose. Generally the VPN connects one firewall or border router with another firewall or border router see Figure 10-4 . To initiate the connection one site attempts to send traffic to the other. This causes the two VPN end points to initiate the VPN. The two end points will negotiate the parameters of the connection depending on the .