Trên toàn thế giới, pháp luật về chữ ký số cũng phát triển như là một cách để cung cấp cho các tài liệu tồn tại dưới dạng điện tử tư cách pháp lý tương tự như các tài liệu giấy và để cung cấp một phương pháp, an toàn, đáng tin cậy, và bị xử phạt về mặt pháp lý để "ký" tài liệu điện tử. | Design and Implementation of the Corporate Security Policy Some implementation details are given as examples of how to carry out part of the policy. Most of the implementation details are found in Chapters 8 9 and 10 which detail specific features and considerations. Note Incidence response handling is also part of the planning and implementation phase but because of its importance and breadth it is detailed separately in Chapter 7 Incident Handling. Physical Security Controls Physical security controls are those controls pertaining to the physical infrastructure physical device security and physical access. Do you expect intruders to tap into your infrastructure to eavesdrop on transmitting data How easy or difficult is it for intruders to gain physical access to the important network infrastructure devices If the corporate network has not yet been created at an existing site you should consider the physical security controls available in its planning phase. For existing networks if a security policy is being created or modified to accommodate changing environments it might be necessary to change the physical infrastructure or the locations of some critical pieces of equipment to ensure an easier security policy imple-mentation. After you have incorporated the physical security controls into the policy as the corporation grows and new sites are added you should consider the network physical security controls as the site is constructed. Physical Network Infrastructure The physical network infrastructure encompasses both the selection of the appropriate media type and the path of the physical cabling the network topography . You want to ensure that no intruder is able to eavesdrop on the data traversing the network and that all critical systems have a high degree of availability. Physical Media Selection From a security point of view the type of cable chosen for various parts of the network can depend on the sensitivity of the information traveling over that cable.