Despite the Internet's continued growth, it increasingly depends on a small set of service providers to support Domain Name System (DNS) and web content hosting. This trend poses many potential threats including susceptibility to outages, failures, and potential censorship by providers. This paper aims to quantify consolidation in terms of popular domains' reliance on a small set of organizations for both DNS and web hosting. We highlight the extent to which a set of relatively few platforms host the authoritative name servers and web content for the top million websites. Our results show that both DNS and web hosting are concentrated, with Cloudflare and Amazon hosting over $30\%$ of the domains for both services. With the addition of Akamai, Fastly, and Google, these five organizations host $60\%$ of index pages in the Tranco top 10K, as well as the majority of external page resources. These trends are consistent across six different global vantage points, indicating that consolidation is happening globally and popular organizations can influence users' online experience across the world.

翻译：尽管互联网持续增长，但其对域名系统（DNS）和Web内容托管的依赖日益集中于少数服务提供商。这种趋势带来了诸多潜在威胁，包括容易遭受服务中断、故障以及服务商可能实施的审查。本文旨在量化这种集中化趋势，通过分析热门域名对少数组织在DNS和Web托管方面的依赖程度。我们揭示了前100万网站中，授权域名服务器和Web内容托管由相对少数平台主导的现象。研究结果表明，DNS和Web托管均呈现高度集中态势，Cloudflare和Amazon承载了超过30%的域名对应上述两种服务。若加上Akamai、Fastly和Google，这五家组织在Tranco前1万排名中托管了60%的索引页面及大部分外部页面资源。这些趋势在六个全球不同观测点具有一致性，表明集中化正在全球范围内发生，且热门组织能够影响世界各地用户的线上体验。