Clarification on Replace-By-Fee (RBF) and Child-Pays-For-Parent (CPFP).

[Ummeettaa]

During my researches to know more about Bitcoin and it's related factors, i came across some strange and new Bitcoin related terms for the first time which are Replace-by-Fee(RBF) and Child's-Pay-for-Parent(CPFP).

I made Further research about them and found out that they are both use in Bitcoin transactions, but i was having a hard time understanding a single meaning of both terms and how they work and related to Bitcoin.

So I thought to bring it up here to seek for more knowledge, understanding and explanations from you all.

What I will love to know about them are;

How the both terms are related to Bitcoin? How they are used in Bitcoin transactions? How they both works in Bitcoin transactions? Which is better to use when transacting in Bitcoin?  And the differences between both of the terms ( Package replace by fee and Child pays for parent)?

[Obim34]

I can refer you to a thread about this same topic I created some time ago.

RBF AND CPFP & What They Do

It didn't have too many discussions, but that should be a good summary, also read the comments.

[Amphenomenon]

This thread will give answer to your question https://bitcointalk.org/index.php?topic=5563629.msg65974488#msg65974488

Both helps to facilitate an ongoing or unconfirmed transactions but the difference is that RBF replaces previous view while CPFP is another transaction facilitating the earlier one(s).

Ps:
Obim34 beat me to this, we provided same link.

[Merit.s]

It's always good to use a noncustodial wallet that has RBF by default so that, you can easily bump your transaction fee if your bitcoin transaction is stucked with low fee in the mempool. RBF helps you to use a higher fee to replace the lower transaction fee simply by increasing it on the fee slide.

CPFP is similar too but you have to use a higher transaction fee for the second transaction in order to entice the miner to confirm both transactions for you including the stucked one with a low transaction fee. I prefer using wallets that has RBF by default. Electrum wallet is one of it.

[Livingleged]

Just understand it this way, that both the RBF and CPFP are all pumping mechanism that help get your transactions confirmed faster when the original fee was too low.
Here is the difference between then;
The RBF is enabled by the sender, it is just replacing the original unconfirmed transaction with another that pay a higher fee.
-The CPFP, the receiver or anyone who can spend the unconfirmed output create a child transaction with one of the output using a higher fee, encouraging the miners to include both the parent  and the child together, because the miners can’t confirm the child without confirming the parent first because the child depends on the parent.
There is more but I can see that others have drop the link to the thread  it’s being discussed already.

[Mia Chloe]

~snip

Read through the links you have been given that's more of what it's about, however I think the most important thing is being able to tell their differences. Most times RBF involves only a single transaction broadcasted CPFP on the other hand is usually more than one transaction.

RBF is broadcasting same transaction with a much higher fee CPFP is making miners confirm a transaction with low fees because it is tied to another one with a bigger fee. Besides miners prefer to confirm bigger fees first.

[coinlary]

You already gotten a perfect reference from obim34, go through it and you will understand it better.

Where did you encounter it, btw? I'm sure they would have some explanation, even if it's not explained in detail and btw, the best way to understand it is to test it and see how it works on-chain.

 It doesn't necessarily have to be on mainnet. Use testnet with some testnet coins to avoid making mistakes that could cost you money. After testing it, you'll understand it much better.

[Agbamoni]

Both are options to bump the fee in accelerating Bitcoin transactions.

However, you can accelerate a Bitcoin transaction using the following suggested tools;

1. ViaBTC
2. BitRef
3. Fujn
4. Mempool.space
5. BitAccelerate

Only ViaBTC allows speedup of bitcoin transaction for free. The rest are either paid or will scam you out of your money when you pay for a premium. Mempool.space is recommended if you need a paid service.