Update to use cashu NUT-24

buds/07.md

@@ -10,12 +10,15 @@ Payment requirements for blob storage.
 
 ## Payment Required
 
-Some servers MAY require payment for file storage. In such cases, these endpoints MUST return a **402 Payment Required** status code:
+Some servers MAY require payment for uploads, downloads, or any other endpoint. In such cases, these endpoints MUST return a **402 Payment Required** status code.
 
-- [HEAD /upload](./01.md#head-sha256---has-blob) (Optional, if [BUD-06](./06.md) is implemented)
-- [PUT /upload](./02.md#put-upload---upload-blob)
-- [HEAD /<sha256>](./01.md#head-sha256---has-blob)
-- [GET /<sha256>](./01.md#get-sha256---get-blob)
+Some endpoints a server may require payment for:
+
+- [`HEAD /upload`](./06.md) to signal that payment is required for the `PUT` request ( if [BUD-06](./06.md) is supported )
+- [`PUT /upload`](./02.md#put-upload---upload-blob) to require payment for uploads
+- [`HEAD /<sha256>`](./01.md#head-sha256---has-blob) to signal that payment is required for the `GET` request
+- [`GET /<sha256>`](./01.md#get-sha256---get-blob) to require payment for downloads ( maybe charge by MB downloaded? )
+- [`HEAD /media`](./05.md) and [`PUT /upload`](./05.md) to require payment for media optimizations ( if [BUD-06](./06.md) is supported )
 
 When payment is required, the server MUST include one or more `X-{payment_method}` header(s), each corresponding to a supported payment method.
 
@@ -25,7 +28,7 @@ The 402 status code and `X-{payment_method}` header is used by the server to inf
 
 Supported payment methods:
 
-- `X-Cashu`: Payment details for the cashu payment method, adhering to the [NUT-18](https://github.com/cashubtc/nuts/blob/main/18.md) standard.
+- `X-Cashu`: Payment details for the cashu payment method, adhering to the [NUT-24](https://github.com/cashubtc/nuts/blob/main/24.md) standard.
 - `X-Lightning`: Payment details for the lightning payment method, adhering to the [BOLT-11](https://github.com/lightning/bolts/blob/master/11-payment-encoding.md) standard.
 
 If a server supports multiple payment methods, it MAY send multiple `X-{payment_method}` headers in the same response.
@@ -39,7 +42,7 @@ X-{payment_method}: "<encoded_payload_according_to_{payment_method}_spec>"
 
 ### `X-Cashu` Header
 
-When using the X-Cashu header, the server MUST adhere to the [NUT-23](https://github.com/cashubtc/nuts/pull/239) standard.
+When using the X-Cashu header, the server MUST adhere to the [NUT-24](https://github.com/cashubtc/nuts/blob/main/24.md) standard.
 
 Example for cashu:
 
@@ -64,7 +67,7 @@ Clients MUST parse and validate the `X-{payment_method}` header received from th
 
 The client MUST provide the payment proof when re-trying the request using the same `X-{payment_method}` header that was chosen. The payment proof MUST align with the payment method specification:
 
-- For cashu the payment proof should be a serialized cashu token according to [NUT-00](https://github.com/cashubtc/nuts/blob/main/00.md#v4-tokens).
+- For cashu the payment proof should be a serialized `cashuB` token in the `X-Cashu` header according to [NUT-24](https://github.com/cashubtc/nuts/blob/main/24.md#client-payment).
 - For lightning the payment proof should be the preimage of the payment request according to [BOLT-11](https://github.com/lightning/bolts/blob/master/11-payment-encoding.md).
 
 Schema:
@@ -82,7 +85,7 @@ X-Cashu: cashuBo2F0gqJhaUgA_9SLj17PgGFwgaNhYQFhc3hAYWNjMTI0MzVlN2I4NDg0YzNjZjE4N
 Example for Lightning:
 
 ```http
-X-Lightning: "966fcb8f153339372f9a187f725384ff4ceae0047c25b9ce607488d7c7e93bba"
+X-Lightning: 966fcb8f153339372f9a187f725384ff4ceae0047c25b9ce607488d7c7e93bba
 ```
 
 **Special Note on HEAD Requests**
@@ -99,4 +102,4 @@ To support future payment methods (e.g., other Layer 2 solutions), the specifica
 
 New methods MUST use a unique `X-{payment_method}` header containing the specific payment details.
 
-New methods MUST adhere their own specification, which MUST be publicly available and linked in the header.
+New methods MUST adhere their own specification, which MUST be publicly available and linked in the header.