Security Policy Fundamentals
This section provides basic information on the purpose, goal, definition, and implementation of a security policy. In addition, this section discusses the flexibility, communication, and management of an established security policy.
Purposes of a Security Policy
The primary purpose of a security policy is to inform users, staff, and managers of those essential requirements for protecting various assets including people, hardware, and software resources, and data assets. The policy should specify the mechanisms through which these requirements can be met.
Another purpose is to provide a baseline from which to acquire, configure, and audit computer systems and networks for compliance with the policy. This also allows for the subsequent development of operational procedures, the establishment of access control rules and various application, system, network, and physical controls and parameters.
Security Policy Goals
The goal of the security policy is to translate, clarify and communicate management's position on security as defined in high-level security principles. The security policies act as a bridge between these management objectives and specific security requirements.
Definition of a Security Policy
A security policy is a formal statement of the rules through which people are given access to an organization's technology, system and information assets. The security policy defines what business and security goals and objectives management desires, but not how these solutions are engineered and implemented.
A security policy should be economically feasible, understandable, realistic, consistent, procedurally tolerable, and also provide reasonable protection relative to the stated goals and objectives of management. Security policies define the overall security and risk control objectives that an organization endorses. The characteristics of good security policies are:
They must be implementable through system administration procedures, publishing of acceptable use guidelines, or other appropriate methods.
They must be enforceable with security tools, where appropriate, and with sanctions, where actual prevention is not technically feasible.
They must clearly define the areas of responsibility for the users, administrators, and management.
They must be documented, distributed, and communicated.
A successful security policy must be flexible. In order for a security policy to be viable for the long term, a security policy should be independent of specific hardware and software decisions, as specific systems choices change rapidly.
In addition, the mechanisms for updating the policy should be clearly spelled out. This includes the process, the people involved, and the people who must sign-off on the changes.
Security Policy Communication
Once security policies have been established, they must be disseminated to all appropriate users, staff, management, vendors, third party processors, and support personnel. Given the nature of your enterprise, it may also be necessary to communicate some or all policies to customers as well. Establishing a record that those involved have read, understood, and agreed to abide by the policy is an essential part of this process.
To ensure that your policies do not become obsolete, you should implement a regular review process of them. That process should include some form of update mechanism so that changes in your organization's operating environment can be quickly translated into your security policy.
We recommend that a specific organization be identified, such as the data security department, and be chartered with the custodianship of your security policy. That organization would then be responsible for conducting a regular review and as applicable, updating your security policy.
Relationship to Standards and Procedures
Security policies embody management's overall security expectations, goals and objectives. To be practical and implementable, policies must be further defined by standards, guidelines, and procedures. These must ensure that all operations are consistent with the intent of the security policies.
Standards, guidelines, and procedures provide specific interpretation of policies and instruct users, customers, technicians, management, and others on how to implement the policies. Your organization should undertake the definition of standards, guidelines, and procedures only after the development and acceptance of security policies, and after specific security mechanisms supporting these policies are determined or implemented.
Implementation in IT Systems
Once policies, guidelines, and procedures are established, appropriate parts of these procedures can be implemented in information-processing systems. In Java™ technology-based systems, for example, some of the policies might become requirements for third-party software such as cryptographic providers, while others would become definitions of roles and access rights to be implemented using the Java Security APIs.
It is important to emphasize, however, that implementation of some policies in information processing systems is never sufficient to ensure that the customer's trust is maintained: It is at least as important that all policies and procedures external to the information-processing system are also correctly enforced and performed. Without correct operation, security can never be guaranteed.
Security policies should be designed to provide effective and economically efficient directives for risk mitigation. Policies should be based upon a formal security stance that is determined by management. In general, a security stance of 'least privilege' can be used in most commercial, financial, Internet, and governmental environments. A typical security stance is:
Security Policy Structure
The basic structure of a security policy should contain the following components:
A statement of the issue that policy addresses.
A statement about your position on the policy.
How the policy applies in the environment.
The roles and responsibilities of those affected by the policy.
What level of compliance to the policy is necessary.
What actions, activities and processes are allowed and which are not.
What are the consequences of non-compliance.
A list of specific topics is also noted in the Sample Data Security Policy and Guidelines template listed in the References section.
Roles and Responsibilities
The development of security policies is predicated upon the participation of various organizations. In general, it is recommended that the following areas participate in this development effort:
- Business management
- Technical management
- Data security
- Risk management
- Systems operations
- Application development
- Network engineering
- Systems administration
- Internal audit
- Human resources
In addition to determining the roles and responsibilities of those involved in the development of security policies, the intended audience for your security policies must also be considered. In general, you must first determine if policies are internal or external or both; and then determine the orientation of the audiences by topical area such as:
- Customers or clients
- Executive management
- Business management
- Technical management
- Employees, temps, contractors