A comparative study of the DNS design with DHT-based alternatives (original) (raw)

"A Comparative Study of Current DNS with DHT-Based Alternatives"

The current Domain Name System (DNS) follows a hierarchical tree structure. Several recent efforts proposed to re-implement DNS as a peer-to-peer network with a flat structure that uses Distributed Hash Tables (DHT) to improve the system availability. In this paper we compare the performance and availability of these two designs, enabled by caching and redundancy in both cases. We show that the caching and redundancy mechanisms in each design are closely bound to its system structure. We further demonstrate that each of the two system structures provides unique advantages over the other, while each has its own shortcomings. Using analysis and tracedriven simulations, we show that hierarchical structure enables high performance caching and that DHT structures provide high degree of robustness against targeted attacks. We further show that the current DNS design offers engineering flexibilities which have been utilized to optimize system performance under typical Internet failures and traffic loads, and which can be further extended to overcome DNS weaknesses against the aforementioned attacks.

An IP address based caching scheme for peer-to-peer networks

GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489), 2003

Distributed hash tables (DHTs), used in a number of current peer-to-peer systems, provide efficient mechanisms for resource location. Systems such as Chord, Pastry, CAN, and Tapestry provide strong guarantees that queries in the overlay network can be resolved in a bounded number of overlay hops, while preserving load balance among the peers. A key distinction in these systems is the way they handle locality in the underlying network. Topology-based node identifier assignment, proximity routing, and proximity neighbor selection are examples of heuristics used to minimize message delays in the underlying network. In this paper, we investigate the use of source IP addresses to enhance locality in overlay networks based on DHTs. We first show that a naive use of source IP address potentially leads to severe resource imbalance due to nonuniformity of peers over the IP space. We then present an effective caching scheme that combines a segment of the source IP with the queried hash-code to effectively localize access and affect replication. Using detailed experiments, we show that this scheme achieves performance gains of up to 41%, when compared to Pastry in combination with the proximity neighbor selection heuristic.

A random structure for optimum cache size distributed hash table (DHT) peer-to-peer design

2002

We propose a new and easily-realizable distributed hash table (DHT) peer-to-peer structure, incorporating a random caching strategy that allows for polylogarithmic search time while having only a constant cache size. We also show that a very large class of deterministic caching strategies, which covers almost all previously proposed DHT systems, can not achieve polylog search time with constant cache size. In general, the new scheme is the first known DHT structure with the following highly-desired properties: (a) Random caching strategy with constant cache size; (b) Average search time of O(log 2 (N )); (c) Guaranteed search time of O(log 3 (N )); (d) Truly local cache dynamics with constant overhead for node deletions and additions; (e) Self-organization from any initial network state towards the desired structure; and (f) Allows a seamless means for various trade-offs, e.g., search speed or anonymity at the expense of larger cache size.

An effective single-hop distributed hash table with high lookup performance and low traffic overhead

Concurrency and Computation: Practice and Experience, 2014

Distributed Hash Tables (DHTs) have been used in several applications, but most DHTs have opted to solve lookups with multiple hops, to minimize bandwidth costs while sacrificing lookup latency. This paper presents D1HT, an original DHT which has a peer-to-peer and self-organizing architecture and maximizes lookup performance with reasonable maintenance traffic, and a Quarantine mechanism to reduce overheads caused by volatile peers. We implemented both D1HT and a prominent single-hop DHT, and we performed an extensive and highly representative DHT experimental comparison, followed by complementary analytical studies. In comparison with current single-hop DHTs, our results showed that D1HT consistently had the lowest bandwidth requirements, with typical reductions of up to one order of magnitude, and that D1HT could be used even in popular Internet applications with millions of users. In addition, we ran the first latency experiments comparing DHTs to directory servers, which revealed that D1HT can achieve latencies equivalent to or better than a directory server, and confirmed its greater scalability properties. Overall, our extensive set of results allowed us to conclude that D1HT can provide a very effective solution for a broad range of environments, from large-scale corporate datacenters to widely deployed Internet applications 1,2 .

Performance Management of Peer-to-Peer Distributed Hash Tables

IFIP International Federation for Information Processing, 2006

P2P networking is a distributed model where entities play both the client and server role. One major problem addressed in this model is the discove~y, searching and routing in a dynamic distributed environment. Among the different envisaged solutions, Distributed Hash Tables (DHT) are very promising. They allow the build of robust content addressable networks. Despite good theoretical performance properties, infrastructures which implement the model need a performance management framework able to monitor them in case of a concrete deployment. In this article we propose a generic performance management information model for DHTs. Our contribution uses a standard management approach based on the Common Information Model (CIM) Metric model.

The case for pushing DNS

2005

We present the case for using a peer-to-peer infrastructure to push DNS name server records to thousands of name servers world wide. We show that such an infrastructure increases the robustness of the DNS in an increasingly hostile Internet. We further show that the overheads of a peer-to-peer DNS infrastructure are both manageable and scalable.

SOLD: Self-Organizing Lookups in DHTs for better Performance over Unstable P2P Overlay Links

The quality of service (QoS) of a distributed hash table (DHT) lookup is gaining importance with the growing number of services adopting the P2P paradigm. Examples of applications that could largely benefit from an improved timeliness and reliability of message exchange in DHTs are Domain Name System (DNS), or even newer types of distributed location-based services in a mobile environment. The bursty effects of Internet traffic on latency, congestion, and loss can change the short term state of the overlay links in the DHT. The quick changes to overlay link/node states cannot be taken into account while structuring long term P2P routes. This paper proposes self-organizing mechanisms to improve the QoS for DHT lookups, without changing the structure of the DHT network. Different kinds of lookup replication techniques are implemented on top of the DHT to restrict the influence of the heterogeneous capabilities of the overlay routes while offering self-adaptive and robust high performance lookups.

Peer-to-Peer Single Hop Distributed Hash Tables

GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference, 2009

Efficiently locating information in large-scale distributed systems is a challenging problem to which Peer-to-Peer (P2P) Distributed Hash Tables (DHTs) can provide a highly scalable and cost-effective solution. However, there is very little experience on using DHTs in performance sensitive environments such as High Performance Computing (HPC) datacenters, and there is no published experimental comparison among lowlatency DHTs. To fill this gap, we conducted an in-depth performance comparison of three proposed low-latency singlehop DHTs namely 1h-Calot, D1HT, and OneHop. Specifically, we compared experimentally the lookup latency and CPU use of D1HT with those of 1h-Calot by running each of them concurrently with the normal workload production for a subset of 1,800 nodes of a heavy-loaded HPC datacenter. In addition, we carried out an analytical performance comparison among the three single-hop DHTs for system sizes of up to 10 million nodes. The results showed that D1HT consistently had the smallest overhead and in most cases it required one order of magnitude less bandwidth than 1h-Calot and OneHop. Overall, the combination of our experimental and analytical results suggests that D1HT can provide a very effective solution for a broad range of environments, from large-scale HPC datacenters to widely deployed Internet P2P applications such as BitTorrent with up to one million peers. This ability to support such a wide range of environments may allow D1HT to be used as an inexpensive and scalable commodity software substrate for largescale distributed applications 1 .

A Case for Unstructured Distributed Hash Tables

2007 IEEE Global Internet Symposium, 2007

Structured peer-to-peer overlays support compelling applications such as large-scale file systems and distributed backup using the distributed hash table (DHT) interface. While unstructured file-sharing systems continue to flourish, wide adoption of structured applications has been elusive. We explore an alternative path to deployment of these applications by asking the question, can structured applications be run on top of unstructured overlays? We build an unstructured distributed hash table (UDHT) on top of state of the art search and topology management mechanisms, and evaluate whether it can sufficiently emulate properties of DHTs to support structured applications.