CISSP Information Systems Security

Answer: B - Protocols determine how computer systems communicate across networks through encapsulation, which allows for the building of a message through protocol stacks. A message is constructed within a program on one computer and then passed down through the protocol’s stack. A protocol at each layer adds its own information to the message; thus, the message grows in size as it goes down the protocol stack. The message is then sent to the destination computer and the encapsulation is reversed by taking the packet apart through the same steps used by the source computer that encapsulated it.