The Internet has evolved through successive architectural abstractions that enabled unprecedented scale, interoperability, and innovation. Packet-based networking enabled the reliable transport of bits; cloud-native systems enabled the orchestration of distributed computation. Today, the emergence of autonomous, learning-based systems introduces a new architectural challenge: intelligence is increasingly embedded directly into network control, computation, and decision-making, yet the Internet lacks a structural foundation for representing and exchanging meaning. In this paper, we argue that cognition alone: pattern recognition, prediction, and optimization, is insufficient for the next generation of networked systems. As autonomous agents act across safety-critical and socio-technical domains, systems must not only compute and communicate, but also comprehend intent, context, and consequence. We introduce the concept of a Semantic Layer: a new architectural stratum that treats meaning as a first-class construct, enabling interpretive alignment, semantic accountability, and intelligible autonomous behavior. We show that this evolution leads naturally to a Syntactic-Semantic Internet. The syntactic stack continues to transport bits, packets, and workloads with speed and reliability, while a parallel semantic stack transports meaning, grounding, and consequence. We describe the structure of this semantic stack-semantic communication, a semantic substrate, and an emerging Agentic Web, and draw explicit architectural parallels to TCP/IP and the World Wide Web. Finally, we examine current industry efforts, identify critical architectural gaps, and outline the engineering challenges required to make semantic interoperability a global, interoperable infrastructure.

翻译：互联网通过连续的架构抽象实现了前所未有的规模、互操作性和创新。基于分组的网络实现了比特的可靠传输；云原生系统实现了分布式计算的编排。如今，自主的、基于学习的系统的出现带来了新的架构挑战：智能日益直接嵌入网络控制、计算和决策中，然而互联网缺乏表示和交换意义的结构性基础。本文认为，仅靠认知——模式识别、预测和优化——对于下一代网络系统是不够的。随着自主智能体在安全关键和社会技术领域行动，系统不仅需要计算和通信，还必须理解意图、上下文和后果。我们引入了语义层的概念：一个新的架构层，将意义视为一等构造，从而实现解释对齐、语义问责和可理解的自主行为。我们表明，这种演进自然地导向了句法-语义互联网。句法栈继续以速度和可靠性传输比特、分组和工作负载，而并行的语义栈则传输意义、基础事实和后果。我们描述了该语义栈的结构——语义通信、语义基板以及新兴的智能体网络，并明确地将其架构与TCP/IP和万维网进行类比。最后，我们审视了当前的行业努力，识别了关键的架构差距，并概述了实现语义互操作性成为全球性、可互操作基础设施所需的工程挑战。