Match the following:
Answer: Option (B).
P - 1, Q - 4, R - 2 is Self Explanatory, but for S-PPP , refer:
Answer is B
SMTP is an application layer protocol used for e-mail transmission.
TCP is a core transport layer protocol.
BGP is a network layer protocol backing the core routing decisions on the Internet
PPP is a data link layer protocol commonly used in establishing a direct connection between two networking
doubt : but Wikipedia says BGP is application layer protocol