Which of the following security threats in client-server e-commerce architectures involves an attacker secretly intercepting and possibly altering communication between two parties?
A Man-in-the-Middle (MITM) attack occurs when an attacker secretly relays and alters communications between two parties who believe they are directly communicating with each other.
A packet-filtering firewall operates at which layer of the OSI model?
Packet-filtering firewalls examine network packets at the Network (IP addresses) and Transport (TCP/UDP port numbers) layers of the OSI model.
Which cryptographic method uses two distinct keys - a public key for encryption and a private key for decryption?
Asymmetric (Public Key) Cryptography utilizes a mathematically linked pair of keys: a public key shared with everyone for encryption and a private key kept secret for decryption.
In digital signatures, which property ensures that the sender cannot deny having sent a specific electronic message or document?
Non-repudiation prevents an individual or organization from denying their actions or the authenticity of a transaction/signature they originated.
S/MIME (Secure/Multipurpose Internet Mail Extensions) is used in e-commerce for which purpose?
S/MIME provides cryptographic security services such as authentication, message integrity, digital signatures, and encryption for MIME data in email communications.