TCP/IP are the protocols that route data around the internet. What are they responsible for?

TCP/IP are the protocols that route data around the internet. What are they responsible for?

• A. DNS handles security; TCP handles routing.
• B. IP handles routing; TCP handles reliability.
• C. IP handles encryption; TCP handles error checking.
• D. TCP handles routing; IP handles reliability.

Answer: (B)

In TCP/IP, routing and reliable delivery are handled by two layers with different jobs. IP is responsible for moving packets from sender to receiver across networks by using addresses and routing decisions; it doesn’t promise that every packet arrives or that they arrive in order. TCP sits on top of IP and provides reliability: it establishes a connection, numbers segments, uses acknowledgments, and retransmits any lost data, so the complete message arrives correctly and in order. Because of these roles, saying that IP handles routing while TCP handles reliability is the best description of their functions.

In TCP/IP, routing and reliable delivery are handled by two layers with different jobs. IP is responsible for moving packets from sender to receiver across networks by using addresses and routing decisions; it doesn’t promise that every packet arrives or that they arrive in order. TCP sits on top of IP and provides reliability: it establishes a connection, numbers segments, uses acknowledgments, and retransmits any lost data, so the complete message arrives correctly and in order. Because of these roles, saying that IP handles routing while TCP handles reliability is the best description of their functions.