Payment Protocol

The five-minute read

One action, walked through

1. Open BIP 70 and read the status line before the examples.
2. Write down the rule in one sentence. A fair version of that sentence is: A protocol for communication between a merchant and their customer, enabling both a better customer experience and better security against man-in-the-middle attacks on the payment process.
3. Name the object that changes: Payment Protocol.
4. Ask what an old client, an old contract, or an offline counterparty does. If the document is silent, the silence is part of the design.

The argument, unpacked

What has to be true

• You are implementing BIP 70 at the status the text itself states: Deployed.
• The object that has to change is Payment Protocol. A neighbouring document with a similar name is not this one.
• Measurements of delay in one year do not travel with the specification.

What happened after the paper

The source marks this deployed. That is a statement about the text, not a promise that every wallet or node has shipped it. Later documents can narrow, replace, or ignore this one. Cite the number you mean.

What to check before you use the idea

• Which message does Payment Protocol add, and which old peer must still be answered?
• What does a node do when the short form fails and the full object is required?
• Which names are normative: Payment Protocol?

Terms

BIP 70

The public text titled Payment Protocol.

Deployed

The document's own label for how finished the text is. It is not a market fact.

The problem the paper names

A node that cannot fetch, filter, or relay the data it is supposed to validate is not a peer of the network the paper describes.

What the design proposes

• A protocol for communication between a merchant and their customer, enabling both a better customer experience and better security against man-in-the-middle attacks on the payment process.
• The current, minimal Bitcoin payment protocol operates as follows: # Customer adds items to an online shopping basket, and decides to pay using Bitcoin.
• # Merchant generates a unique payment address, associates it with the customer's order, and asks the customer to pay.

How the mechanism is specified

• Taken from the specification, the next constraint is: The current, minimal Bitcoin payment protocol operates as follows: # Customer adds items to an online shopping basket, and decides to pay using Bitcoin.
• Locate Payment Protocol in BIP 70 and apply it to one transaction or call.
• Then check the failure the class of rule always has: a node that did not upgrade, a reverted call, a replayed signature, or a peer that does not speak the message.

What this page does not treat as proven

• A peer protocol is not a consensus rule. A peer can disconnect. A block is still valid or not on its own.
• Measurements of delay in one year do not travel with the specification.
• The source marks this deployed. That is a statement about the text, not a promise that every wallet or node has shipped it.

Why a venture studio still reads it

Use BIP 70 when a pitch says 'Payment Protocol' without saying whether the rule is consensus, policy, or an interface. The number is the citation. The pitch is not.