Which type of network model describes the functions that must be completed at a particular layer, but does not specify exactly how each protocol should work?

Which type of network model describes the functions that must be completed at a particular layer, but does not specify exactly how each protocol should work?

• hierarchical design model
• reference model
• protocol model
• TCP/IP model

Explanation: There are two common types of network communication models:
Protocol model - This model closely matches the structure of a particular protocol suite and describes the functions that occur at each layer of protocols within the suite. The TCP/IP model is an example of a protocol model.
Reference model - The primary purpose is to aid in a clearer understanding of the functions and processes necessary for network communications.This type of model does not specify exactly how a function should be accomplished. The OSI model is an example of a reference model.

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