The most important protocols of the Network Configuration Management are those that ensure interoperability and the smooth operation between different subnets. These include the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP) and the Internet Protocol (IP). The first transmission control functionality, the second forwarding, the third has addressing / routing features in the internal switching nodes.
As mentioned, the communication structure is in layers (similar to the architecture model ISO-OSI) protocol stack or 5 levels from the physical layer to the application layer: According to this structure, the TCP or UDP occupies the upper level ( transport level) than IP (network layer).
Above these are the type of application protocols related to the particular service to be performed. Below there are transport protocols typical of local, metropolitan and wide area to be interconnected, links of connection (backhaul) and dorsal (backbone), and others placed at the same level.
Basically an initial data packet (payload) starts at the application level from a host through vertically from top to bottom all the various protocol layers that add to the package itself, in a procedure called the enveloping.
Gradually additional information (headers) are laid in a structure of service information (overhead), when the total package thus obtained, once transmitted to the physical layer on the transmission medium, reaches the destination, takes one unpacking backwards from bottom to top and each level law and processes the information of the respective header.
The logical structure of the service is based on Internet standards developed by the Internet Engineering Task Force (IETF) with strictly approved documents known as Request for Comments (“Request for Comments”, RFC), and application-level protocols of the World Wide Web Consortium (W3C).
In particular, from the point of view of the use of services of the application layer, the logical architecture of the Internet can be either client-server or peer-to-peer networks. Each terminal host or network, because of its accessibility, is also identified by an static or dynamic IP address (ie manually assigned by the network or DHCP). While the resources to benefit are typically present on the server, reachable from the client under the mnemonic indication provided by the so-called URL, thanks to the use of a web browser.
The conversion from mnemonic address URL to IP address, required for routing effective in switching nodes in the network management software, is provided by the DNS, while the communication between client and server is established following the definition of the socket in which in addition to the addresses IP client and server are also known as ports involved in the communication service to be performed.