Questions related to how Bitcoin finds other peers to communicate with.
Questions tagged [peer-discovery]
79 questions
191
votes
2 answers
How do Bitcoin clients find each other?
What protocols or algorithms are Bitcoin clients using in order to find their peers? I learnt that BitTorrent clients may rely on central computers called trackers. Do Bitcoin clients need any kind of central servers or nodes in order to operate?
Ning
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46
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3 answers
How does the bitcoin client make the initial connection to the bitcoin network?
Once the bitcoin client is connected to a machine (or multiple machines) on the bitcoin network, they can share information (e.g. the block-chain, IP addresses of other nodes, etc). I understand how this peer-to-peer architecture is robust to nodes…
Ciaran
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26
votes
4 answers
What is a DNS seed node vs a Seed Node?
I've seen references to both strewn around. Specifically, is there a bitcoin client running at the DNS seeds or seed nodes?
Shamoon
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20
votes
5 answers
Sync with bitcoin-qt very slow (0,01%)
I have the issue that my node's synchronisation is very slow. I am 14 weeks behind and it estimates to take 12 weeks to get synced. The synchronisation rate per hour is only 0,01%.
I have a fast broadband connection and no other issues with this PC.…
michL
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14
votes
4 answers
Why doesn’t Bitcoin use UDP to do Blockpropagation?
Bitcoin uses TCP for P2P but why is UDP not used? Modern day internet has relatively low packet loss rate so UDP is reliable. Even if some packets are dropped the peers can always request for the blocks. With TCP, the network is rather staticly…
user2584960
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10
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2 answers
What is the difference between the bitcoind command line options "addnode" and "connect"?
As seen here: https://en.bitcoin.it/wiki/Running_Bitcoin#Command-line_arguments
-addnode=ip Add a node to connect to and attempt to keep the connection open
-connect=ip Connect only to the specified node(s)
Both of those…
user3145
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9
votes
1 answer
How do bitcoin nodes initially find peers?
In all materials related to bitcoin, the people talk about the p2p bitcoin network.
OK, but there should be a central server that connects the peers to each one.
Like the torrent sites. The torrents are p2p but before you can start talking with the…
tonko
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8
votes
1 answer
How does one become a DNS seed for Bitcoin Core?
How does the process work? Do Core devs add a DNS seed based on reputation or what?
luisschwab
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7
votes
1 answer
Can any Bitcoin client do local peer discovery and blockchain synchronization?
Usually, when a full Bitcoin client such as bitcoind, Bitcoin-QT, or Multibit start on a fresh installation, they connect "to the network" to download the blockchain. If someone has multiple computers or devices, they could end up downloading the…
Colin Dean
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7
votes
1 answer
How peer discovery works after connecting to hardcoded nodes?
I am tinkering with the bitcoin source code and trying to understand the exact working of peer discovery mechanism in the testnet mode for which I have made the following changes:
Disabled the DNS seed discovery in order to force bitcoind to…
bawejakunal
- 507
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7
votes
2 answers
Could the BGP attack be used to split the Bitcoin network?
I just learnt about the BGP attack:
http://www.wired.com/2014/08/isp-bitcoin-theft/
http://www.secureworks.com/cyber-threat-intelligence/threats/bgp-hijacking-for-cryptocurrency-profit/
The attacker was able to redirect the miners to its own pool to…
Manish
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7
votes
1 answer
What is a block-relay-only connection? What is it used for?
Modern versions of bitcoin core establish a fixed number of outbound connections: 8 outbound-full-relay connections and 2 block-relay-only connections. What is the purpose of block-relay-only connections and how are they used?
Here are two example…
vnprc
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6
votes
2 answers
What exactly does the scary option "Allow incoming connections" do in Bitcoin Core?
Software authors seem to enjoy consciously freaking me out by having vaguely or entirely uncommented options in their software with very ominous labels.
In Bitcoin Core's settings, it says "[X] Allow incoming connections", which has an entirely…
Dujon W.
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6
votes
1 answer
How secure are the DNS servers for Bitcoin?
With the version 0.6, Bitcoin introduced the DNS servers that populate the initial peers for new clients. How secure are those servers in terms of being immune to takedown attacks, or injection of malicious data?
ThePiachu
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6
votes
1 answer
What can an attacker do if they compromise a DNS seeder?
Recently Bitcoin Core developer Luke-jr was hacked and has stated that we should consider anything owned by him to be compromised. This would include his DNS seeder at dnsseed.bitcoin.dashjr.org. If an attacker has indeed compromised this DNS…
Andrew Chow
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