A network graph visualization demonstrates a proxy chain architecture using D3 v6 with SVG rendering. The diagram shows main, sub, proxy, and agent nodes connected by HTTPS, callback, tunnel, and reverse links, with each node displaying a Font Awesome icon. The code uses `d3.linkHorizontal` for curved link paths, `d3.zoom` for pan and zoom interactions, and predefined fixed node coordinates positioned as percentages of the SVG dimensions. Node and link styling is applied through D3 selections with custom CSS classes.