Coalescing Connections to Improve Network Privacy and Performance

Web pages often contain numerous embedded subresources, such as JavaScript, CSS, and image files, which can significantly impact page load times due to additional DNS lookups, TCP connections, and TLS handshakes. Connection Coalescing, or Connection Reuse, is a technique that allows reusing a TLS connection across different domains, potentially improving users' experience by reducing extraneous requests on page loads and optimizing resource utilization. This study investigated the feasibility of Connection Coalescing in real-world traffic, focusing on privacy and performance benefits. Results showed that approximately 50% of requests to cdnjs from experiment group sites were coalesced, with Chrome creating about 78% fewer TLS connections compared to the control group. Firefox created roughly 22% fewer connections. Overall, connection coalescing demonstrated potential privacy and performance benefits without causing harm to users' experience on the Internet. Future directions include exploring more aggressive connection reuse methods and evaluating support among different browser vendors.