Changing Kademlia Metric - Unidirectional Property Importance

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By : Kate Proykova

Date : November 27 2020, 11:01 PM

I hope this helps . You wouldn't be dealing with kademlia anymore. There are man other routing algorithms which use different distance metrics, some even non-uniform distance metrics, but they do not rely on kademlia-specific assumptions and sometimes incorporate other features to compensate for some undesirable aspect of those metrics.
Since there can be ties in the metric (two candidates for each point), lookups could no longer converge on a precise set of closest nodes.

code :

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Kademlia routing table and distance metric

By : Byung Joon Yoon

Date : March 29 2020, 07:55 AM

I hope this helps . I think I got it. The common prefix same bucket thing is indeed directly related to the xor values, so its indeed sorting them. I found those slides pretty helpful: http://heim.ifi.uio.no/michawe/teaching/p2p-ws08/p2p-5-6.pdf

Adding new nodes to Kademlia, building Kademlia routing tables

By : Hiroshi Uyama

Date : March 29 2020, 07:55 AM

it helps some times I'm assuming you've read the Kademlia paper. Here's an excerpt from my article An Introduction to Kademlia DHT & How It Works
Some background information:

code :

foreach(K-Buckets as KB)         
    1. NN generates a random NodeId `RNID` // A NodeId that will be in KB 
    2. NN sends LookupRequest(RNID) to the K-Closest nodes it knows to RNID. 
    3. The response will be K nodes closest to RNID.
    4. NN now fills KB.

Kademlia XOR metric properties purposes

By : user2395278

Date : March 29 2020, 07:55 AM

I think the issue was by ths following , I can only speak for Kademlia, maybe someone else can provide a more general answer. In the meantime...
d(x,x) = 0 d(x,y) > 0, if x != y

Better understanding Kademlia's XOR Integer Metric

By : rahul

Date : March 29 2020, 07:55 AM

Hope that helps It's not correct because
binary.Uvarint() can only decode numbers within 64 bits, and your rawBytes is 256 bits The "varint" encoding (as commented in https://golang.org/src/encoding/binary/varint.go) is basically not compatible with raw bytes.

code :

func xorDistance(node string, otherNode string) *big.Int {
    var rawBytes [32]byte
    for i := 0; i < 32; i++ {
        rawBytes[i] = node[i] ^ otherNode[i]
    }
    return big.NewInt(0).SetBytes(rawBytes[:])
}

Can XOR metric be used to implement DHT without Kademlia?

By : Jonathan Seitz

Date : March 29 2020, 07:55 AM

I wish did fix the issue. No.
Without kademlia's routing table you would have no guarantee that any node's neighbor list would actually contain contacts that are closer to the target key and thus could help your query converge towards the target.