is heading the data) which includes the address infor- mation of the sending and/or receiving end and certain control information regarding the given type of information carried in the packet, called a payload. This technology was packet-switching and there were two main competitors for it in the 1990s: the European-based ATM (asynchronous transfer mode) and the US-based Internet. The ATM was mainly based on the philosophy of traditional telecommunications where all intelligence was placed in the network nodes on the side of the telecom operators while the users had simpler equipment (such as telephone devices). The virtual circuits (introduced by the ATM) are established on signaling messages between the end nodes (which is similar to establishing a telephone call in a telephone network). Meanwhile, the Internet was created on several principles that made it a global success, from which the following ones can be considered as the most important: There is separation of applications and services from the underlying transport tech- nologies (e.g. mobile or fixed access networks, transport networks). All network nodes and user terminals have the main IP stack based on transport layer protocols, which are primarily UDP (user datagram protocol) [4] and TCP (transmis- sion control protocol) [5], over the IP in its two existing versions, IP version 4 [6] and IP version 6 [7]. The traditional telecommunications layering protocol and the IP model are compared in Figure 1.2. Initially, in the early days (the 1970s) the IP model was based on three layers: the Interface layer at the bottom, network control program (NCP) in the middle, and the application layer on the top. In 1981 the NCP split into TCP (or UDP) over IP, SO they became four protocol layers as the native Internet model from the 1980s. However, the network interface layer is typically split into the physical layer and data-link layer by all standard development organizations (SDOs), SO with such classification the basic IP layering model has five layers. The ne