For the past 4 years, I've been using this configuration to obfuscate my node from the network. I employ two full nodes, one of which exclusively communicates with the node connected to the internet. The rationale behind this setup is to ensure that the node hosting my wallet isn't directly accessible from the internet, significantly reducing the risk of a hack and increased privacy. My question is whether this is the optimal approach or if there's a more efficient solution that doesn't require two nodes.
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What you want is a reverse jumphost in place of PC1.
The jumphost is the internet facing system, and better it be a cheap VPS, these are good for this because it gives you an IP somewhere else.
Since it's only for connectivity it doesn't need hardly any resources, can be a few dollar a month option from a lowendbox deal.
On your actual full node system, you'll use iptables/firewall (ideally a firewall appliance infront of it too) to prevent any connectivity into this system to keep it dark.
The only rule you allow is an outbound rule to the external jumphost from PC2, can be over SSH for simplicity or wireguard if you're so inclined.
End result is your full node at your home looks like it has the VPS IP, and the only traffic that can hit it comes from the jumphost on the port specificed (bitcoin traffic port)
To go a step further, the jumphost could itself have another firewall that only allows traffic to select gossip peers or applications you might use.
Ignore anyone telling you to use Tor, they're just parroting nonsense they read somewhere else:
If you are using this scenario for onchain only, is not necessary the decoy node, is kind of useless. But yes, in some cases you can use it like that, for example running a core node alone and to that you link a neutrino client for a LN node or multiple other LN nodes as "clients".
If you are using this scenario for a LN node, then yes, could add more obfuscation 👍
I don't use this setup for LN, why do you say it's not necessary the decoy node (PC1 right?)?
PC1 full BTC core node is just a simple node that broadcast and verify txs in public blocks, will never reveal anything about your wallets connected to it.
You can connect to that node multiple wallets from many local or remote IPs without revealing anything. You do not need another node to connect to a local node.
Example: https://www.sparrowwallet.com/docs/connect-node.html
Also you can run an Electrum server / Fulcrum or Esplora server that is connected to that full node and offer SPV sync for your multiple wallets (remote or local IPs).
By storing the wallet on PC1, am I not increasing the risk of being hacked? Considering that the node broadcasting the transactions can be identified?
No, why is a risk? Is just an app that sign a tx (I suppose you are using Electrum or Sparrow).
No it can't. Is just a random node. Even if I know your public IP, I can't "hack" your wallet behind that node. I need a "door" to enter and that door is only when you open it (phishing attacks, spyware, malware scanning your keyboard). I think you watched too many "hacker movies"...
You can't know that a bitcoin node have behind 1 or 1000 other clients using its block sync.
The risk is that it will become a hot wallet. I don't use Electrum or Sparrow in this wallet.
From what I've read in the past, it's not that random. When the full node connects to peers, it connects to the closest peers and I think it has a limit (maybe configurable, but I think the normal limit is 10).
Bad.
Yes a simple node have a limit of 10 peers. You can increase that limit but that will imply also to open the port 8333 and will have huge impact on your bandwidth used, IP etc. I would not recommend doing that, only if you really want to be a REAL public seeder node.
Here is a transcript that answer your question in a more detailed way:
https://btctranscripts.com/andreas-antonopoulos/2018-08-30-andreas-antonopoulos-home-network-security
this ?
I saved you time sharing that part of the transcript.
Reading also his book "Mastering Bitcoin" could help you a lot understanding all these technical aspects.
My advice: don't complicate things too much. The biggest threat is the user's sloppiness not how many levels of security you add.
Very good question anyways!
I could be wrong, but I think running an electrum server is what you need.
Can you elaborate on that?
Yeah, so you run a bitcoin node like you're doing and the seperate electrum server queries and indexes UTXO'S that your wallet needs. It basically stops other nodes from gathering info from your Bitcoin node.
Probably someone more technical can explain it better than that.
I keep mine under a blanket so no one can see it.
But that makes it a hot wallet!
It's fine. It has a fan in it.
Why not use tor instead?
Sus much?