CompTIA CASP CAS-004 Updated Exam

Watermarking is a technique of adding an identifying image or pattern to an original image to protect its ownership and authenticity. Watermarks can be customized to include specific information about the external party, such as their name, logo, or date of receipt. This way, if any draft images are leaked to the public, the firm can trace back the source of the leak and take appropriate actions. Verified References:

Cipher feedback (CFB) is a mode of operation for block ciphers that allows them to encrypt streaming data. CFB uses an initialization vector (IV) and a block cipher to generate a keystream that is XORed with the plaintext to produce the ciphertext. CFB has low latency because it can encrypt each byte or bit of plaintext as soon as it arrives, without waiting for a full block. CFB is suitable for streaming data because it does not require padding or block synchronization.

B. Cipher block chaining message authentication code (CBC-MAC) is a mode of operation for block ciphers that provides both encryption and authentication. CBC-MAC uses an IV and a block cipher to encrypt the plaintext and generate a MAC value that is appended to the ciphertext. CBC-MAC has high latency because it requires the entire message to be processed before generating the MAC value. CBC-MAC is not suitable for streaming data because it requires padding and block synchronization.

C. Cipher block chaining (CBC) is a mode of operation for block ciphers that provides encryption only. CBC uses an IV and a block cipher to encrypt each block of plaintext by XORing it with the previous ciphertext block. CBC has high latency because it requires a full block of plaintext before encryption. CBC is not suitable for streaming data because it requires padding and block synchronization.

D. Electronic codebook (ECB) is a mode of operation for block ciphers that provides encryption only. ECB uses a block cipher to encrypt each block of plaintext independently. ECB has low latency because it can encrypt each block of plaintext as soon as it arrives. However, ECB is not suitable for streaming data because it requires padding and block synchronization. Moreover, ECB is insecure because it does not use an IV and produces identical ciphertext blocks for identical plaintext blocks.

The indicator that shows when a company might not be viable after a disaster is the maximum tolerable downtime (MTD). MTD is the maximum amount of time that a business process or function can be disrupted without causing unacceptable consequences for the organization. MTD is a key metric for business continuity planning and disaster recovery, as it helps determine the recovery time objective (RTO) and the recovery point objective (RPO) for each process or function. If the actual downtime exceeds the MTD, the organization may face severe losses, reputational damage, regulatory penalties, or even bankruptcy. Verified References:

The administrator should use SAN certificates to support multiple domain names while minimizing the amount of certificates needed. SAN stands for Subject Alternative Name, which is an extension of a certificate that allows it to include multiple fully-qualified domain names (FQDNs) within the same certificate. For example, a SAN certificate can secure and mail.example.org with one certificate. SAN certificates can reduce the cost and complexity of managing multiple certificates for different domains. SAN certificates can also support wildcard domains, such as *.example.com, which can cover any subdomain under that domain. Verified References: