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35 votes
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How can I setup Bitcoin to be anonymous with Tor?

This is not a thorough schooling on Tor and only shows how to configure it to work together with Bitcoin Core. Bitcoin Core includes Tor integration When Tor is correctly setup on your system, Bitcoin ...
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29 votes
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How are bitcoin transactions and the blockchain transferred over the internet?

The Bitcoin P2P network The Bitcoin P2P network is a randomly-wired gossip network. This means that all nodes make arbitrary connections to other peers (using various ways to discover new addresses) ...
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25 votes
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Can someone please explain FIBRE to me like I'm 5 and why is it useful?

First the "why it matters": Fibre (Fast Internet Bitcoin Relay Engine) is a protocol which attempts to deliver Bitcoin blocks around the world with delays as close to the physical limits as ...
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15 votes
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Bitcoin protocol and Wireshark

Someone wrote a Bitcoin protocol decoder for Wireshark, several years ago. I assume it was included in the Wireshark distribution. Wireshark simply knows about the Bitcoin protocol. There is no magic ...
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12 votes
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What are the benefits of Invertible Bloom Lookup Tables for Bitcoin?

Invertible Bloom lookup tables can be used in many different ways, but the first paper you linked to explicitly proposes to use them to find differences between two data sets stored on different hosts ...
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12 votes
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Are there any Bitcoin wallets with native I2P integration?

C++ may be viewed by some as more suitable for Bitcoin use than Java which I2P currently heavily relies upon https://github.com/monero-project/kovri Kovri: To cover, veil, wrap (Esperanto). A ...
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11 votes

What's the status of alternative full node implementations?

Update: Coin Dance has an excellent table of node implementations with descriptions and links at the bottom of their Bitcoin Nodes Summary page. Below are the implementations I've found. I'm not sure ...
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9 votes
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What is the P2P technology/protocol used by Bitcoin to find nodes and distribute messages across them?

Bitcoin has its own custom wire protocol using TCP. Peer discovery is by address rumoring, where connected nodes gossip about other potential available peers. When a node is new and has nobody to ...
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9 votes
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Improvements that could be made to how bitcoin propagates its transactions and blocks?

The answer partially depends on on what you mean by "how bitcoin propagates" and "improvements"-- Fibre transmits blocks vanishingly close to the lowest latency possible, but at the expense of using ...
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9 votes
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How are transactions propagated through the bitcoin network? (In-depth)

I read briefly in a paper that there is some sort of transaction queue that the node keeps for each neighbor and that they will only select a random (?) amount of those transactions and send in an INV ...
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8 votes
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How to store data on the blockchain?

then you have 25 letters in base58, and that's like 17 bytes. 20, actually. So, you have to pay like 0.0001 BTC for the transaction fee, and after that you can add data to that transaction at a ...
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8 votes
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How many peers do you need to securely synchronize with the blockchain?

One! Your full node will check every transaction and every block for validity while synchronizing. You therefore can be sure that whatever blockchain data your node accepts follows all rules of ...
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7 votes
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If bitcoin is decentralized then who keeps track of computers in network

Nobody keeps track of all the computers in the network, or at least not as part of core network functionality. There are sites that attempt to track nodes (such as https://bitnodes.21.co/), but they ...
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7 votes

What is a Feeler Connection? When is it used?

A feeler connection is a short-lived outbound connection that only starts up after your node has established the required 8 outbound connections and 2 block-relay-only outbound connections. The ...
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  • 231
6 votes
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Can an attacker create many nodes that approve blocks without work?

You're essentially talking about a "fork" - or a separate chain. It wouldn't and couldn't interface with bitcoin - merely work (at best) alongside it. Exchanges, merchants, and official bitcoin ...
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  • 96
6 votes
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What is the benefit of opening port 8333 to a client?

If you don't want to, you don't have to open ports at all. You'll still have a full node, it will just have fewer connections. Full nodes usually make 8 outgoing connections and can have many more ...
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  • 6,169
6 votes

How to confirm how many peers a node has?

When a node requests one of it's neighbours for a list of it's peers, that node responds with a list of all of it's neighbours. No it doesn't. It responds with list of nodes that its aware of being ...
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6 votes
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What is the oldest Bitcoin Core Client that can in theory sync to the chain tip?

The oldest version that can sync is 0.8.6. This is the version that first used LevelDB instead of BDB. Both the IRC node discovery and the protocol message changes occurred several versions prior.
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6 votes
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How do network nodes "connect" - amateur level

I have no idea what a "network" really is. I googled and read about LAN/WAN. Are these the types of network we're talking about? No. A network is really just "a group of connected ...
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6 votes
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To run a full node, should I get a static IP address from my ISP?

To run a Bitcoin full node you don't need to have a static IP address as when your IP address changes you should still be able to find peers and connect to them. However, if you want to maintain the ...
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6 votes

Can "Block" Message send multiple blocks?

It sends exactly one block. If you want to send multiple blocks, you need multiple messages.
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6 votes
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What is the maximum, realistic P2P message payload size?

Since Bitcoin Core pull request 5843, incoming messages larger than MAX_PROTOCOL_MESSAGE_LENGTH are rejected. This constant was initially set to 2 MiB, but later (as part of the segwit changes) ...
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5 votes
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Is Bitcoin a fully decentralized network, or how do clients connect to the network?

The various approaches the core client takes are described in some detail on the Bitcoin wiki. Once you're connected to the network, your peers can tell you about more peers, so the big question is, ...
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  • 4,327
5 votes

How to store data on the blockchain?

It's been done. It's lame. It's spam. You're incurring cost on the whole network for perpetuity (and no, the fee doesn't pay for that). If you really can't stop yourself look at OP_RETURN as that's ...
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  • 6,169
5 votes
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Is it possible to use bitcoin core on Mac OS Sierra saving the data on the network drive?

Core (more specific levelDB, the database library used) does not support network drives. Also, the UTXO access (chainstate) must be as fast as possible and should run on an internal drive, ideally an ...
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5 votes

Can't specify rpcport for testnet

For any of addnode, connect, port, bind, rpcport, rpcbind, and wallet you should move them into the [test] and/or [main] sections of your bitcoin.conf. You can also move any other setting that you ...
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5 votes

Does a Node connect to all the peers?

A node is only called a peer if you're connected to it. So by definition you are always connected to all your peers. I assume you're asking whether you're connected to every node in the network. The ...
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5 votes
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Malicious full nodes causing denial of service attacks

There are significantly more than 10k full nodes on the network. The 10k figure is simply the number of reachable nodes which listen publicly for new connections. There are many more times that amount ...
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  • 3,190
5 votes

With peerblockfilters=1 hundreds of "btcwire 0.5.0/neutrino" connections are downloading TB from my Bitcoin node

It appears that btcwire is the Bitcoin p2p module of btcd and neutrino is Lightning Labs's implementation of BIP157/158 (compact client-side block filters (CBF)). I suspect that the agent identifier ...
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  • 62.4k

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