The domain name resolution into IP addresses can significantly delay connection establishments on the web. Moreover, the common use of recursive DNS resolvers presents a privacy risk as they can closely monitor the user's browsing activities. In this paper, we present a novel HTTP response header allowing web server to provide their clients with relevant DNS records. Our results indicate, that this resolver-less DNS mechanism allows user agents to save the DNS lookup time for subsequent connection establishments. We find, that this proposal saves at least 80ms per DNS lookup for the one percent of users having the longest round-trip times towards their recursive resolver. Furthermore, our proposal decreases the number of DNS lookups and thus improves the privacy posture of the user towards the used recursive resolver. Comparing the security guarantees of the traditional DNS to our proposal, we find that resolver-less DNS achieves at least the same security properties. In detail, it even improves the user's resilience against censorship through tampered DNS resolvers.
The DNS Anonymity Service combines a broadcast mechanism for popular DNS records with an anonymity network to conduct additional DNS lookups @cite_15 . Unlike our proposal, the DNS Anonymity Service causes additional network traffic for downloading the broadcasted DNS records and suffers additional network latency when the client resolves hostnames via the anonymity network. In total, the performance gains of this clean-slate approach are vague as they depend on the user's browsing behavior. Furthermore, this approach does not integrate well into the existing DNS and requires additional Internet infrastructure to be deployed.
@cite_15
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We propose a dedicated DNS Anonymity Service which protects users' privacy. The design consists of two building blocks: a broadcast scheme for the distribution of a "top list" of DNS hostnames, and low-latency Mixes for requesting the remaining hostnames unobservably. We show that broadcasting the 10,000 most frequently queried hostnames allows zero-latency lookups for over 80 of DNS queries at reasonable cost. We demonstrate that the performance of the previously proposed Range Queries approach severely suffers from high lookup latencies in a real-world scenario. Popular anonymous communication systems often require sending packets through a sequence of relays on dilated paths for strong anonymity protection. As a result, increased end-to-end latency renders such systems inadequate for the majority of Internet users who seek an intermediate level of anonymity protection while using latency-sensitive applications, such as Web applications. This paper serves to bridge the gap between communication systems that provide strong anonymity protection but with intolerable latency and non-anonymous communication systems by considering a new design space for the setting. More specifically, we explore how to achieve near-optimal latency while achieving an intermediate level of anonymity with a weaker yet practical adversary model (i.e., protecting an end-host's identity and location from servers) such that users can choose between the level of anonymity and usability. We propose Lightweight Anonymity and Privacy (LAP), an efficient network-based solution featuring lightweight path establishment and stateless communication, by concealing an end-host's topological location to enhance anonymity against remote tracking. To show practicality, we demonstrate that LAP can work on top of the current Internet and proposed future Internet architectures. Existing IP anonymity systems tend to sacrifice one of low latency, high bandwidth, or resistance to traffic-analysis. High-latency mix-nets like Mixminion batch messages to resist traffic-analysis at the expense of low latency. Onion routing schemes like Tor deliver low latency and high bandwidth, but are not designed to withstand traffic analysis. Designs based on DC-nets or broadcast channels resist traffic analysis and provide low latency, but are limited to low bandwidth communication. In this paper, we present the design, implementation, and evaluation of Aqua, a high-bandwidth anonymity system that resists traffic analysis. We focus on providing strong anonymity for BitTorrent, and evaluate the performance of Aqua using traces from hundreds of thousands of actual BitTorrent users. We show that Aqua achieves latency low enough for efficient bulk TCP flows, bandwidth sufficient to carry BitTorrent traffic with reasonable efficiency, and resistance to traffic analysis within anonymity sets of hundreds of clients. We conclude that Aqua represents an interesting new point in the space of anonymity network designs. Name services are critical for mapping logical resource names to physical resources in large-scale distributed systems. The Domain Name System (DNS) used on the Internet, however, is slow, vulnerable to denial of service attacks, and does not support fast updates. These problems stem fundamentally from the structure of the legacy DNS.This paper describes the design and implementation of the Cooperative Domain Name System (CoDoNS), a novel name service, which provides high lookup performance through proactive caching, resilience to denial of service attacks through automatic load-balancing, and fast propagation of updates. CoDoNS derives its scalability, decentralization, self-organization, and failure resilience from peer-to-peer overlays, while it achieves high performance using the Beehive replication framework. Cryptographic delegation, instead of host-based physical delegation, limits potential malfeasance by namespace operators and creates a competitive market for namespace management. Backwards compatibility with existing protocols and wire formats enables CoDoNS to serve as a backup for legacy DNS, as well as a complete replacement. Performance measurements from a real-life deployment of the system in PlanetLab shows that CoDoNS provides fast lookups, automatically reconfigures around faults without manual involvement and thwarts distributed denial of service attacks by promptly redistributing load across nodes.