TCP 4 layers

1. The 4 layers of the TCP/IP model
TCP/IP functionality is divided into four layers, each of which includes specific protocols:
The application layer provides applications with standardized data exchange. Its protocols include HTTP, FTP, Post Office Protocol 3, Simple Mail Transfer Protocol and
Simple Network Management Protocol. At the application layer, the payload is the actual application data.
The transport layer is responsible for maintaining end-to-end communications across the network. TCP handles communications between hosts and provides flow control,
multiplexing and relia bility. The transport protocols include TCP and User Datagram Protocol, which is sometimes used instead of TCP for special purposes.
The network layer, also called the internet layer, deals with packets and connects independent networks to transport the packets across network boundaries. The network
layer protocols are IP and Internet Control Message Protocol, which is used for error reporting.
The physical layer, also known as the network interface layer or data link layer, consists of protocols that operate only on a link -- the network component that
interconnects nodes or hosts in the network. The protocols in this lowest layer include Ethernet for local area networks and Address Resolution Protocol.
Difference between LAN, MAN and WAN
Prerequisite – Types of area networks – LAN, MAN, and WAN
LAN stands for local area network. It is a group of network devices that allow communication between various connected devices. Private ownership has control over
the local area network rather than the public. LAN has a short propagation delay than MAN as well as WAN. It covers smaller areas such as colleges, schools, hospitals,
and so on.
MAN stands for metropolitan area network. It covers a larger area than LAN such as small towns, cities, etc. MAN connects two or more computers that reside within
the same or completely different cities. MAN is expensive and should or might not be owned by one organization.
WAN stands for wide area network. It covers a large area than LAN as well as a MAN such as country/continent etc. WAN is expensive and should or might not be owned
by one organization. PSTN or satellite medium is used for wide area networks.