can we send bitcoin to ip addresses?

i was reading satoshi nakamoto's post on p2p foundation, and i clicked bitcoin.org link in introduction and just for curiosity searched it on wayback machine to see how the website looked like in 2009,
but, after scrolling i saw this image..

"If the recipient is online, you can enter their IP address and it will connect, get a new public key and send the transaction with comments."
really... is it possible to send bitcoin on a ip address if we are online? or i am wrong? just started to learn

only one reply in 2009 by "Sepp Hasslberge"?

Sending Bitcoin to IP addresses is no longer possible.

--Knight Hider

It's removed because it is very inaccurate and insecure. Bitcoin communications are never encrypted and thus your ISP or anyone on your network could respond with their own address. Besides, there is no tangible benefits to doing so. The message part is local, just a memo for you to indicate what the transaction is for.

There are some things that are no longer possible because they were removed. The first is to be sending to IP address which people on this forum and other bitcoin users have used befor, but this is not secure like sending directly to your bitcoin address. The other one that is possible before was to send to public key, but it is not possible again. The only way you can now send bitcoin is only through the use of bitcoin address.

Quote from: _act_ on August 02, 2023, 02:14:28 PM

The other one that is possible before was to send to public key, but it is not possible again. The only way you can now send bitcoin is only through the use of bitcoin address.

IP sending could be secure, if the path that the data transfer goes through can be guaranteed to be secure. But that'll probably require some form of pre-shared key or authentication. But it isn't too useful regardless.

You can. P2PK is still standard, it's just that most wallets don't support or show their user an option to do so.

I can recall that this topic was made before even though i might have answers on that topic too. Well, here is mine, IP should be secure like there are many layers on internet and only the experienced ones or the most careful ones will use the IP in only severe conditions and if they would have used then they must have secured the connection first. As, i think it must not be a preferred way back then well that's what i assumed from this because many legendary members are so careful in such cases.

So, the best practice must be sending on Wallet address instead of IP where both parties have to be online while making the transaction.

Quote from: ranochigo on August 02, 2023, 02:31:52 PM

Quote from: _act_ on August 02, 2023, 02:14:28 PM

The other one that is possible before was to send to public key, but it is not possible again. The only way you can now send bitcoin is only through the use of bitcoin address.

You can. P2PK is still standard, it's just that most wallets don't support or show their user an option to do so.

Wow! I’ve never heard about this option. Which wallets do still support such kind of transfers? Probably, Bitcoin Core, right? And what about any other, not so ponderous? It would be very interesting to create such transaction and to look at it in a public explorer.

Quote from: internetional on August 02, 2023, 06:08:25 PM

You do not need to try anything like that, P2PK was used before bitcoin address was created which was P2PKH, which means you will pay to public key hash which is bitcoin address, instead of paying to public key directly. There are now other address types that can be used for payment which is what you should better be using.

Quote from: internetional on August 02, 2023, 06:08:25 PM

Bitcoin Core. If you're going to P2PK, then you'll have to spend with a wallet that accepts your private key as a P2PK type instead of a P2PKH type. Most of the transactions in the earlier days are P2PK, not P2PKH. Blockexplorers tend to translate them into a P2PKH type but that is incorrect.

If you want to use P2PK, then at least use compressed key. For example:

Code:

04 678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb6 49f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f //uncompressed, don't use this
03 678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb6 //compressed, use that instead

Also, instead of P2PK, you could switch to Taproot, then Schnorr signatures will be applied, and nobody will know, how many keys were aggregated.

Quote from: _act_ on August 02, 2023, 06:30:15 PM

You do not need to try anything like that, P2PK was used before bitcoin address was created which was P2PKH, which means you will pay to public key hash which is bitcoin address, instead of paying to public key directly. There are now other address types that can be used for payment which is what you should better be using.

To be clear the option to pay to address (ie. P2PKH scripts and addresses) was not something to be added later. They were available from the first release that is version 0.1.0. The only reason why P2PK is seen in all early blocks is that the P2PK outputs were the default output type that the bitcoin core miner chose.

Quote from: ranochigo on August 03, 2023, 02:42:05 AM

Quote from: internetional on August 02, 2023, 06:08:25 PM

Thank you very much. I have looked for old transactions and found such type of address. E.g. Hal’s one: 0411db93e1dcdb8a016b49840f8c53bc1eb68a382e97b1482ecad7b148a6909a5cb2e0eaddfb84c cf9744464f82e160bfa9b8b64f9d4c03f999b8643f656b412a3

Mempool.space still considers these symbols as a legitimate Bitcoin address.

Quote from: internetional on August 03, 2023, 07:06:24 PM

Mempool.space still considers these symbols as a legitimate Bitcoin address.

No, it doesn't. Transaction - f5e26c8b82401c585235c572ba8265f16f7d9304ed8e31c198eab571754f5331 - is paying the coinbase reward of block 30 to a P2PK output. It rightly notes that it's a P2PK (not an address), and it shows the uncompressed public key below.

Quote from: internetional on August 03, 2023, 07:06:24 PM

P2PK is still standard and block explorers should still identify them as such. Some of the block explorers erroneously identify them as a P2PKH address type instead which is wrong. Interestingly, Bitcoin addresses were used for receiving payments from the start but Pay-To-IP feature and mining both uses P2PK instead. Hence, Hal Finney transaction could just be using Pay-To-IP.

Quote from: ranochigo on August 04, 2023, 03:10:02 AM

Hence, Hal Finney transaction could just be using Pay-To-IP.

It appears to have been working for a while, as it was removed from Bitcoin Core v0.8.0 Bitcointalk pull request Github https://github.com/bitcoin/bitcoin/pull/1904

After a little research, they even tried to add the IP address next to the Bitcoin address, or domain name and SSL cert. I don't know if these ideas were applied, but their idea is more like routers between IPV4 and IPV6.

urn:bitcoin.org:19vcWM6EEbQHVdN2W8NXv9ySgsPjbZ6gU3@12.34.56.78

https://bitcointalk.org/index.php?topic=158.msg1322#msg1322

Based on some comments, it seems that this feature was used, but I don't know if it was with the domain name and bitcoin address or just for the IP address.

Quote from: BlackHatCoiner on August 03, 2023, 07:12:37 PM

Quote from: internetional on August 03, 2023, 07:06:24 PM

Mempool.space still considers these symbols as a legitimate Bitcoin address.

Hmm... When I type this public key in their search field, they find it as an address.

Quote from: internetional on August 04, 2023, 05:14:20 PM

Hmm... When I type this public key in their search field, they find it as an address.

Technically they shouldn't show you anything because public key is not a P2PK (nor is it P2PKH or any other address type). When we say P2PK we are talking about a specific script that contains the public key (pushdata + OP_CheckSig).

Quote from: internetional on August 04, 2023, 05:14:20 PM

Hmm... When I type this public key in their search field, they find it as an address.

The search bar part, yeah, incorrect, but they've indeed distinguished it from other standard outputs like P2PKH, which is enough for me.

Quote from: pooya87 on August 05, 2023, 05:06:00 AM

Well, yes, but why not showing you the balance of that particular public key? You can argue the same for P2PKH, that we're talking about a specific script that contains the RIPEMD-160 hash.

I didn't know it was possible to send Bitcoin using an IP address. Glad to know that it was stopped.
I believe this is an insecure method to send Bitcoin as there might be several wallets in the same IP.
Moreover, the Ip address reveals their location.

Quote from: BlackHatCoiner on August 05, 2023, 07:53:18 AM

Well, yes, but why not showing you the balance of that particular public key? You can argue the same for P2PKH, that we're talking about a specific script that contains the RIPEMD-160 hash.

It is entirely possible that it's just buggy and they're too lazy to fix it.
It could be that based on their search request history they came to the conclusion that some users are indeed using their public key to check their balance. But considering that in today's available wallet softwares addresses are used not P2PK, they convert that pubkey to different address types and the website is redirected to the first one that has been used otherwise show the default one which is P2PKH.
The bug is where their indexed database counts balance in P2PK outputs as the P2PKH balance.