What is Information Security?CHAPTER 1 5 Confidentiality Availability Integrity FIGURE 1.1 The CIA Triad balance,and any other information needed to communicate to the bank from which the funds are being drawn.The bank will maintain the confidentiality of the transaction with the ATM and the balance change in the account after the funds have been withdrawn.If at any point in the transaction confidentiality is compromised,the results could be bad for the individual,the owner of the ATM,and the bank,potentially resulting in what is known in the information security field as a breach. Confidentiality can be compromised by the loss of a laptop containir g data,a person looking over our shoulder while we type a password,attach- ment being sent to the wrong person,an attacker penetrating our systems,or similar issues. INTEGRITY Integrity refers to the ability to prevent our data from being changed in an unauthorized or undesirable manner.This could mean the unauthorized change or deletion of our data or portions of our data.or it could mean an authorized,but undesirable changeor deletion of ou data Tomaintan ine we not only y need to h th eans to ed ch o be We can see a good example of mechanisms that allow us to control integrity in the file systems of many modern operating systems such as Windows and Linux. For purposes of preventing unauthorized changes,such systems often imple- ment permissions that restrict what actions an unauthorized user can perform on a ndesirable ortant when we are discussing the data that vides theouofor other decisions.If an attacker were to alter the data t pro What is Information Security? CHAPTER 1 5 balance, and any other information needed to communicate to the bank from which the funds are being drawn. The bank will maintain the confidentiality of the transaction with the ATM and the balance change in the account after the funds have been withdrawn. If at any point in the transaction confidentiality is compromised, the results could be bad for the individual, the owner of the ATM, and the bank, potentially resulting in what is known in the information security field as a breach. Confidentiality can be compromised by the loss of a laptop containing data, a person looking over our shoulder while we type a password, an e-mail attach￾ment being sent to the wrong person, an attacker penetrating our systems, or similar issues. Integrity Integrity refers to the ability to prevent our data from being changed in an unauthorized or undesirable manner. This could mean the unauthorized change or deletion of our data or portions of our data, or it could mean an authorized, but undesirable, change or deletion of our data. To maintain integ￾rity, we not only need to have the means to prevent unauthorized changes to our data but also need the ability to reverse authorized changes that need to be undone. We can see a good example of mechanisms that allow us to control integrity in the file systems of many modern operating systems such as Windows and Linux. For purposes of preventing unauthorized changes, such systems often imple￾ment permissions that restrict what actions an unauthorized user can perform on a given file. Additionally, some such systems, and many applications, such as databases, can allow us to undo or roll back changes that are undesirable. Integrity is particularly important when we are discussing the data that pro￾vides the foundation for other decisions. If an attacker were to alter the data Confidentiality Availability Integrity Figure 1.1 The CIA Triad