TCP (Transmission Control Protocol) ensures reliable, ordered data delivery via a connection-oriented handshake, contrasting with UDP’s lightweight, connectionless approach. Analyzing each service:
C. HTTP (Hypertext Transfer Protocol):Uses TCP (port 80) for web traffic. TCP’s reliability ensures HTML, images, etc., arrive intact. HTTPS (TCP 443) extends this with TLS. RFC 2616 mandates TCP.
A. SNMP (Simple Network Management Protocol):Defaults to UDP (port 161) for monitoring devices. UDP’s speed suits its lightweight queries, though TCP variants exist (rarely used).
B. NTP (Network Time Protocol):Uses UDP (port 123) per RFC 5905. UDP minimizes latency for time sync, tolerating occasional packet loss.
D. IKE (Internet Key Exchange):Part of IPsec, uses UDP (port 500) per RFC 7296. UDP suits its negotiation phase; TCP isn’t standard.
Security Implications:TCP services like HTTP are more prone to state-based attacks (e.g., SYN floods) than UDP counterparts. CNSP likely contrasts TCP vs. UDP in protocol analysis.
Why other options are incorrect:
A, B, D:All default to UDP for efficiency, not TCP’s reliability.
Real-World Context:Firewalls prioritize TCP 80/443 rules for HTTP/HTTPS, while UDP 123 is opened for NTP servers.References:CNSP Official Study Guide (Network Protocols); RFC 2616 (HTTP), RFC 1155 (SNMP).