Reasons For Using Layered Protocol. What Is Meant By Layered Protocol?

Hi Mynsai - I got this from Wikipedia - It's very technical so I hope you understand about computers. Hope it helps.

Protocol layering

In modern protocol design, protocols
are "layered". Layering is a design principle which divides the
protocol design into a number of smaller parts, each of which
accomplishes a particular sub-task, and interacts with the other parts
of the protocol only in a small number of well-defined ways.
For example, one layer might describe how to encode text (with ASCII, say), while another describes how to inquire for messages (with the Internet's simple mail transfer protocol, for example), while another may detect and retry errors (with the Internet's transmission control protocol), another handles addressing (say with IP, the Internet Protocol), another handles the encapsulation of that data into a stream of bits (for example, with the point-to-point protocol), and another handles the electrical encoding of the bits, (with a V.42 modem, for example).
Layering allows the parts of a protocol to be designed and tested without a combinatorial explosion
of cases, keeping each design relatively simple. Layering also permits
familiar protocols to be adapted to unusual circumstances. For example,
the mail protocol above can be adapted to send messages to aircraft.
Just change the V.42 modem protocol to the INMARS LAPD data protocol used by the international marine radio satellites.
The reference model usually used for layering is the OSI seven layer model,
which can be applied to any protocol, not just the OSI protocols. In
particular, the Internet Protocol can be analysed using the OSI model.

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