Explanation
A brief explanation of the benefit of expenditures in the budget helps to convey the context of how the purchases that are being requested meet goals and objectives, which in turn helps build credibility for the information security function or program. Explanations of benefits also help engage senior management in the support of the information security program. While the budget should consider all inputs and recommendations that are received from the business, the budget that is ultimately submitted to management for approval should include only those elements that are intended for purchase. TCO may be requested by management and may be provided in an addendum to a given purchase request, but is not usually included in an annual budget. Baseline comparisons (cost comparisons with other companies or industries) may be useful in developing a budget or providing justification in an internal review for an individual purchase, but would not be included with a request for budget approval.

Security architecture explains the use and relationships of security mechanisms. Security metrics measure improvement within the security practice but do not explain the use and relationships of security technologies. Process improvement models and network topology diagrams also do not describe the use and relationships of these technologies.