Huawei Huawei Huawei China Mobile This document specifies a topological addressing scheme, Path-Aware Semantic Addressing (PASA), that enables IP packet stateless forwarding. The forwarding decision is based solely on the destination address structure. This document focuses on carrying IP packets across an LLN (Low power and Lossy Network), in which the topology is quite static, the location of the nodes is fixed for long period of time, and the connection between the nodes is also rather stable. These specifications describe the PASA architecture, along with PASA address allocation, forwarding mechanism, routing header format, and IPv6 interconnection support.