What is IPS – Internet Protocol Suite?

TCP/IP is the de facto protocol that modern networks use. Although you can think of TCP/IP as a single protocol, it’s actually a combination of two protocols Transmission Control Protocol (ICP) and the Internet Protocol (IP). These two protocols form part of the Internet Protocol Suite (IPS), a conceptual model of how network protocols send network traffic over the internet that breaks down network communication into four layers,

These four layers form a protocol stack. The following list explains each layer of the IPS:

Link layer (layer 1)

This layer is the lowest level and describes the physical mechanisms used to transfer information between nodes on a local network. Well-known examples include Ethernet (both wired and wireless) and Point-to-Point Protocol (PPP).

Internet layer (layer 2)

This layer provides the mechanisms for addressing network nodes. Unlike in layer 1, the nodes don’t have to be located on the local network. This level contains the IP; on modern networks, the actual protocol used could be either version 4 (IPv4) or version 6 (IPv6).

Transport layer (layer 3)

This layer is responsible for connections between clients and servers, sometimes ensuring the correct order of packets and providing service multiplexing. Service multiplexing allows a single node to support multiple different services by assigning a different number for each service; this number is called a port. TCP and the User Datagram Protocol (UDP) operate on this layer.

Application layer (layer 4)

This layer contains network protocols, such as the HyperText Transport Protocol (HTTP), which transfers web page con-tents; the Simple Mail Transport Protocol (SMTP), which transfers email; and the Domain Name System (DNS) protocol, which converts a name to an address of a node on the network. Throughout this book, we’ll focus primarily on this layer.