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I'm currently learning more and more about the Bitcoin protocol and I`m wondering if using an IRC channel as the source to find your Bitcoin peers is a potential weak link of the Bitcoin network?

From what I understand the channel is hosted on irc.lfnet.org , so if that website was brought down normal clients would be unable to find peers?

ThePiachu
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2 Answers2

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They'd have no problem finding peers for several reasons:

  1. Once the client finds a single peer, it can get a list of peers from that peer.

  2. The client has a built-in list of about 500 peer IP addresses known to be stable.

  3. The client knows several DNS names (such as bitseed.xf2.org and dnsseed.bluematt.me) that resolve to lists of Bitcoin peers.

  4. The client stores peer addresses in a local database.

In fact, IRC has been removed from the Bitcoin client since 2013.

Nick ODell
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David Schwartz
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New clients that do not yet have addresses stored in the addr.dat will use irc as a bootstrapping mechanism. Even with this limited role, using IRC exposes a weakness: https://en.bitcoin.it/wiki/Weaknesses#Cancer_nodes

The IRC bootstrapping will be going away in the future [Edit: as David write, it is deprecated in the latest version], in favor of the dnsseed method: - http://bitcointalk.org/index.php?topic=24457.msg305424#msg305424 - http://en.bitcoin.it/wiki/Network#IRC

Stephen Gornick
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