What is IEEE 802.3 (Ethernet)

Cyber Physical Systems are based on a number of nodes connected through a communication network, which can interact with the environment. In this chapter, a completely open-source architecture of a cyber physical system based on off-the-shelf components will be presented. Its main characteristics are high real-time capabilities and the use of both wired and IEEE 802.11 wireless technologies for communication. The Linux operating system installed on common personal computers and communication technologies derived from the IT world make the proposed architecture highly customizable, inexpensive and performing. Moreover, the presence of a time synchronization service allows the sharing of time between nodes. Specific software and techniques, some based on synchronized nodes, are used to increase determinism and reliability in both wired and wireless extensions.