This paper deals with embedded system networking support, which is aimed at applications based on distributed components interconnected by wired Internet and wireless sensor networks. It presents a safety and security-driven approach to embedded system networking that offers reusable patterns for designs aiming at various application domains. After introducing terminology dealing with functionality and dependability, the article copes with industrial, sensor network and Internet based architectures. It discusses an integrated networking framework stemming from the IEEE 1451.1 smart transducer interface standard, which is an object-based networking model supporting client-server and publish-subscribe communication patterns in group messaging, and from the IP multicast communication, mediating safe and secure access to wireless sensor networks through Internet. The case study demonstrates how clients can access groups of wireless smart pressure and temperature sensors and valves, which monitor and control gas pipelines effectively through Internet using developed networking architecture that respects prescribed requirements for application dependent safety and security.