Simple Module Kademlia

File: Overlay/Kademlia/Kademlia.ned

C++ definition: click here

The main module of the Kademlia implementation

Author: Sebastian Mies

Usage diagram:

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KademliaModules

Implementation of the Kademlia DHT overlay as described in "Kademlia: A peer-to-peer information system based on the XOR metric" by P. Maymounkov and D. Mazieres, published in "In Proceedings of IPTPS02"

Parameters:

Name Type Description
localPort numeric

base overlay parameters

debugOutput bool

enable debug output

keyLength numeric

overlay key length in bits

drawOverlayTopology bool

draw arrow to successor node?

hopCountMax numeric

maximum number of overlay hops

joinOnApplicationRequest bool

only join the overlay on application request

useCommonAPIforward bool

enable CommonAPI forward() calls

routeMsgAcks bool

use RPCs for route messages

recNumRedundantNodes numeric

numRedundantNodes for recursive routing

lookupRedundantNodes numeric

lookup parameters

lookupParallelPaths numeric

number of parallel paths

lookupParallelRpcs numeric

number of nodes to ask in parallel

lookupSecure bool

true, if all nodes should be identified with a ping

lookupMerge bool

true, if parallel Rpc results should be merged

lookupStrictParallelRpcs bool

limited the number of concurrent rpcs to parameter parallelRpcs

lookupUseAllParallelResponses bool

merge all parallel responses from earlier steps

lookupNewRpcOnEveryTimeout bool

send a new RPC immediately after an RPC timeouts

lookupNewRpcOnEveryResponse bool

send a new RPC after every response, even if there was no progress

lookupFinishOnFirstUnchanged bool

finish lookup, if the last pending RPC returned without progress

lookupFailedNodeRpcs bool

communicate failed nodes lookups

routingType string

default routing mode (iterative, semi-recursive,...)

collectPerHopDelay bool

delay statistics for single hops

minSiblingTableRefreshInterval numeric

kademlia parameters

minBucketRefreshInterval numeric

bucket refresh delay

maxStaleCount numeric

number of timeouts before node removal

k numeric

number of paths (size of k-bucket)

b numeric

network diameter O(log_{2^(b)})

s numeric

number of siblings

pingNewSiblings bool

ping new unknown siblings?

activePing bool

ping new neighbors?

Gates:

Name Direction Description
from_udp [ ] input

gate from the UDP layer

to_udp [ ] output

gate to the UDP layer

from_app input

gate from the application

to_app output

gate to the application

direct_in input

gate for sendDirect

Source code:

simple Kademlia
    parameters:
        // base overlay parameters
        localPort : numeric,             // UDP port for Kademlia messages
        debugOutput : bool,              // enable debug output
        keyLength : numeric,             // overlay key length in bits
        drawOverlayTopology : bool,      // draw arrow to successor node?
        hopCountMax : numeric,           // maximum number of overlay hops
        joinOnApplicationRequest : bool ,// only join the overlay on application
                                         // request
        useCommonAPIforward : bool,      // enable CommonAPI forward() calls
        routeMsgAcks : bool,            // use RPCs for route messages
        recNumRedundantNodes : numeric, // numRedundantNodes for recursive routing

        // lookup parameters
        lookupRedundantNodes : numeric,  // number of next hops in each step
        lookupParallelPaths : numeric,   // number of parallel paths
        lookupParallelRpcs : numeric,    // number of nodes to ask in parallel
        lookupSecure : bool,             // true, if all nodes should be
                                         // identified with a ping
        lookupMerge : bool,              // true, if parallel Rpc results should
                                         // be merged
        lookupStrictParallelRpcs: bool, // limited the number of concurrent rpcs to parameter parallelRpcs
        lookupUseAllParallelResponses: bool, // merge all parallel responses from earlier steps
        lookupNewRpcOnEveryTimeout: bool, // send a new RPC immediately after an RPC timeouts
        lookupNewRpcOnEveryResponse: bool, // send a new RPC after every response, even if there was no progress
        lookupFinishOnFirstUnchanged: bool, // finish lookup, if the last pending RPC returned without progress                                        
        lookupFailedNodeRpcs : bool,     // communicate failed nodes lookups
        routingType : string, // default routing mode (iterative, semi-recursive,...)
        collectPerHopDelay : bool,       // delay statistics for single hops

        // kademlia parameters
        minSiblingTableRefreshInterval : numeric, // siblingTable refresh delay
        minBucketRefreshInterval : numeric,       // bucket refresh delay
        maxStaleCount : numeric,                  // number of timeouts before
                                                  // node removal

        k : numeric,                     // number of paths (size of k-bucket)
        b : numeric,                     // network diameter O(log_{2^(b)})
        s : numeric,                     // number of siblings

        pingNewSiblings : bool,           // ping new unknown siblings?
        activePing : bool;                // ping new neighbors?

    gates:
        in: from_udp[];                  // gate from the UDP layer
        out: to_udp[];                   // gate to the UDP layer
        in: from_app;                    // gate from the application
        out: to_app;                     // gate to the application
        in: direct_in;                   // gate for sendDirect
endsimple