DNSR: Domain Name Suffix-based Routing in Overlay Networks Dept. of Computer Science & Engineering. University of California - Riverside CS202 – Advanced O.S Spring ’03 DNSR: Domain Name Suffix-based Routing in Overlay Networks Demetrios Zeinalipour-Yazti

Introduction Most overlay networks don’t match the underlying topology Transcontinental connections are expensive. It would be desirable to keep the bulk of the P2P traffic within the same domain

Motivation Analyzing the Gnutella Network [D. Zeinalipour & T. Folias, cs204 Course Project] We analyzed ~300,000 IP addresses. 58.73% of Gnutella IPs belongs to only 20 ISPs. Organizing Peers into domains rather than loosely interconnecting them might be feasible

DNSR Idea DNSR:Domain-Name Suffix-based Routing Decentralized Routing Algorithm that attempts to keep P2P traffic within the same domain. DNSR defines three Level factors per peer: Sibling Factor (sfi) Parent Factor (pfi) Children Factor (cfi) DNSR also defines a similarity function -suffix

DNSR Topology Given that each node maintains the Level Factors we end up with a semi-hierarchical topology.

Joining a DNSR Topology A node obtains a random list from an out-of-band mechanism (e.g. hostcache). It probes for “best” entry point with Lookup

Searching a DNSR Topology Searching can be done with a variety of techniques (BFS, Random BFS,….) The bottom-line with all techniques is that the bulk of the traffic remains within the same domain

Experimental Setup Scenario We generate a DNSR topology and a Random Topology of 1000 nodes with following distributions We deploy the 1000 real nodes on 25 machines We run a number of queries and observe the distribution of hosts contacted in each case.

Experimental Evaluation Each node reads its settings from the filesystem All nodes are launched concurrently with ssh public/private keys making the bootstrapping easy.

Experimental Results We connect to a .rr.com host Level 0 We connect to a .rr.com host Submit 40 queries and count the number of hosts contacted C. In a random topology C matches the actual distribution of hosts In a DNSR topology most of the hosts contacted are .com hosts for level 0.

Experimental Results Level 1 For Level 1 we can see that in DNSR topology we will contact more .rr.com hosts than with a random topology. Therefore more traffic remains within same domain Sibling Factor was 66%. If it was larger then 24% would be larger

DNSR Demo Follows… Dept. of Computer Science & Engineering. University of California - Riverside DNSR Demo Follows…