Clarify that network.protocol.version represents negotiated version

.chloggen/817.yaml

@@ -0,0 +1,4 @@
+change_type: bug_fix
+component: network
+note: Clarifies that network.protocol.version represents negotiated version
+issues: [ 686 ]

docs/attributes-registry/network.md

@@ -22,13 +22,13 @@ These attributes may be used for any network related operation.
 | `network.peer.address` | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>Peer address of the network connection - IP address or Unix domain socket name. | `10.1.2.80`; `/tmp/my.sock` |
 | `network.peer.port` | int | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>Peer port number of the network connection. | `65123` |
 | `network.protocol.name` | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>[OSI application layer](https://osi-model.com/application-layer/) or non-OSI equivalent. [1] | `amqp`; `http`; `mqtt` |
-| `network.protocol.version` | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>Version of the protocol specified in `network.protocol.name`. [2] | `3.1.1` |
+| `network.protocol.version` | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>The actual version of the protocol used for network communication. [2] | `1.1`; `2` |
 | `network.transport` | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>[OSI transport layer](https://osi-model.com/transport-layer/) or [inter-process communication method](https://wikipedia.org/wiki/Inter-process_communication). [3] | `tcp`; `udp` |
 | `network.type` | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>[OSI network layer](https://osi-model.com/network-layer/) or non-OSI equivalent. [4] | `ipv4`; `ipv6` |
 
 **[1]:** The value SHOULD be normalized to lowercase.
 
-**[2]:** `network.protocol.version` refers to the version of the protocol used and might be different from the protocol client's version. If the HTTP client has a version of `0.27.2`, but sends HTTP version `1.1`, this attribute should be set to `1.1`.
+**[2]:** If protocol version is subject to negotiation (for example using [ALPN](https://www.rfc-editor.org/rfc/rfc7301.html)), this attribute SHOULD be set to the negotiated version. If the actual protocol version is not known, this attribute SHOULD NOT be set.
 
 **[3]:** The value SHOULD be normalized to lowercase.
 

docs/dotnet/dotnet-http-metrics.md

@@ -54,7 +54,7 @@ Notes:
 |---|---|---|---|---|
 | `http.connection.state` | string | State of the HTTP connection in the HTTP connection pool. | `active`; `idle` | Required |
 | [`network.peer.address`](../attributes-registry/network.md) | string | Remote IP address of the socket connection. | `10.1.2.80` | Recommended |
-| [`network.protocol.version`](../attributes-registry/network.md) | string | HTTP protocol version of the connection in the connection pool. [1] | `1.1`; `2`; `3` | Recommended |
+| [`network.protocol.version`](../attributes-registry/network.md) | string | The negotiated version of the protocol associated with connection in the connection pool. [1] | `1.1`; `2`; `3` | Recommended |
 | [`server.address`](../attributes-registry/server.md) | string | Host identifier of the ["URI origin"](https://www.rfc-editor.org/rfc/rfc9110.html#name-uri-origin) HTTP request is sent to. [2] | `example.com`; `10.1.2.80`; `/tmp/my.sock` | Required |
 | [`server.port`](../attributes-registry/server.md) | int | Port identifier of the ["URI origin"](https://www.rfc-editor.org/rfc/rfc9110.html#name-uri-origin) HTTP request is sent to. [3] | `80`; `8080`; `443` | Conditionally Required: [4] |
 | [`url.scheme`](../attributes-registry/url.md) | string | The [URI scheme](https://www.rfc-editor.org/rfc/rfc3986#section-3.1) component identifying the used protocol. | `http`; `https`; `ftp` | Recommended |
@@ -90,7 +90,7 @@ of `[ 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30, 60, 120, 300 ]`.
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
 | [`network.peer.address`](../attributes-registry/network.md) | string | Peer address of the network connection - IP address or Unix domain socket name. | `10.1.2.80`; `/tmp/my.sock` | Recommended |
-| [`network.protocol.version`](../attributes-registry/network.md) | string | HTTP protocol version of the connection in the connection pool. [1] | `1.1`; `2`; `3` | Recommended |
+| [`network.protocol.version`](../attributes-registry/network.md) | string | The negotiated version of the protocol associated with connection in the connection pool. [1] | `1.1`; `2`; `3` | Recommended |
 | [`server.address`](../attributes-registry/server.md) | string | Host identifier of the ["URI origin"](https://www.rfc-editor.org/rfc/rfc9110.html#name-uri-origin) HTTP request is sent to. [2] | `example.com`; `10.1.2.80`; `/tmp/my.sock` | Required |
 | [`server.port`](../attributes-registry/server.md) | int | Port identifier of the ["URI origin"](https://www.rfc-editor.org/rfc/rfc9110.html#name-uri-origin) HTTP request is sent to. [3] | `80`; `8080`; `443` | Conditionally Required: [4] |
 | [`url.scheme`](../attributes-registry/url.md) | string | The [URI scheme](https://www.rfc-editor.org/rfc/rfc3986#section-3.1) component identifying the used protocol. | `http`; `https`; `ftp` | Recommended |
@@ -119,7 +119,7 @@ of `[ 0.005, 0.01, 0.025, 0.05, 0.075, 0.1, 0.25, 0.5, 0.75, 1, 2.5, 5, 7.5, 10
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
 | [`http.request.method`](../attributes-registry/http.md) | string | HTTP request method. [1] | `GET`; `POST`; `HEAD` | Recommended |
-| [`network.protocol.version`](../attributes-registry/network.md) | string | HTTP protocol version of the connection in the connection pool. [2] | `1.1`; `2`; `3` | Recommended |
+| [`network.protocol.version`](../attributes-registry/network.md) | string | The negotiated version of the protocol associated with connection in the connection pool. [2] | `1.1`; `2`; `3` | Recommended |
 | [`server.address`](../attributes-registry/server.md) | string | Host identifier of the ["URI origin"](https://www.rfc-editor.org/rfc/rfc9110.html#name-uri-origin) HTTP request is sent to. [3] | `example.com`; `10.1.2.80`; `/tmp/my.sock` | Required |
 | [`server.port`](../attributes-registry/server.md) | int | Port identifier of the ["URI origin"](https://www.rfc-editor.org/rfc/rfc9110.html#name-uri-origin) HTTP request is sent to. [4] | `80`; `8080`; `443` | Conditionally Required: [5] |
 | [`url.scheme`](../attributes-registry/url.md) | string | The [URI scheme](https://www.rfc-editor.org/rfc/rfc3986#section-3.1) component identifying the used protocol. | `http`; `https`; `ftp` | Recommended |

docs/dotnet/dotnet-kestrel-metrics.md

@@ -96,7 +96,7 @@ of `[ 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30, 60, 120, 300 ]`.
 |---|---|---|---|---|
 | [`error.type`](../attributes-registry/error.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>The full name of exception type. [1] | `System.OperationCanceledException`; `Contoso.MyException` | Conditionally Required: if and only if an error has occurred. |
 | [`network.protocol.name`](../attributes-registry/network.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>[OSI application layer](https://osi-model.com/application-layer/) or non-OSI equivalent. [2] | `http`; `web_sockets` | Recommended |
-| [`network.protocol.version`](../attributes-registry/network.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>Version of the protocol specified in `network.protocol.name`. [3] | `1.1`; `2` | Recommended |
+| [`network.protocol.version`](../attributes-registry/network.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>The actual version of the protocol used for network communication. [3] | `1.1`; `2` | Recommended |
 | [`network.transport`](../attributes-registry/network.md) | string | [OSI transport layer](https://osi-model.com/transport-layer/) or [inter-process communication method](https://wikipedia.org/wiki/Inter-process_communication). [4] | `tcp`; `unix` | Recommended |
 | [`network.type`](../attributes-registry/network.md) | string | [OSI network layer](https://osi-model.com/network-layer/) or non-OSI equivalent. [5] | `ipv4`; `ipv6` | Recommended: if the transport is `tcp` or `udp` |
 | [`server.address`](../attributes-registry/server.md) | string | Server domain name if available without reverse DNS lookup; otherwise, IP address or Unix domain socket name. [6] | `example.com`; `10.1.2.80`; `/tmp/my.sock` | Recommended |
@@ -107,7 +107,7 @@ of `[ 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 30, 60, 120, 300 ]`.
 
 **[2]:** The value SHOULD be normalized to lowercase.
 
-**[3]:** `network.protocol.version` refers to the version of the protocol used and might be different from the protocol client's version. If the HTTP client has a version of `0.27.2`, but sends HTTP version `1.1`, this attribute should be set to `1.1`.
+**[3]:** If protocol version is subject to negotiation (for example using [ALPN](https://www.rfc-editor.org/rfc/rfc7301.html)), this attribute SHOULD be set to the negotiated version. If the actual protocol version is not known, this attribute SHOULD NOT be set.
 
 **[4]:** The value SHOULD be normalized to lowercase.
 
@@ -253,15 +253,15 @@ different processes could be listening on TCP port 12345 and UDP port 12345.
 | Attribute  | Type | Description  | Examples  | Requirement Level |
 |---|---|---|---|---|
 | [`network.protocol.name`](../attributes-registry/network.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>[OSI application layer](https://osi-model.com/application-layer/) or non-OSI equivalent. [1] | `http`; `web_sockets` | Recommended |
-| [`network.protocol.version`](../attributes-registry/network.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>Version of the protocol specified in `network.protocol.name`. [2] | `1.1`; `2` | Recommended |
+| [`network.protocol.version`](../attributes-registry/network.md) | string | ![Stable](https://img.shields.io/badge/-stable-lightgreen)<br>The actual version of the protocol used for network communication. [2] | `1.1`; `2` | Recommended |
 | [`network.transport`](../attributes-registry/network.md) | string | [OSI transport layer](https://osi-model.com/transport-layer/) or [inter-process communication method](https://wikipedia.org/wiki/Inter-process_communication). [3] | `tcp`; `unix` | Recommended |
 | [`network.type`](../attributes-registry/network.md) | string | [OSI network layer](https://osi-model.com/network-layer/) or non-OSI equivalent. [4] | `ipv4`; `ipv6` | Recommended: if the transport is `tcp` or `udp` |
 | [`server.address`](../attributes-registry/server.md) | string | Server domain name if available without reverse DNS lookup; otherwise, IP address or Unix domain socket name. [5] | `example.com`; `10.1.2.80`; `/tmp/my.sock` | Recommended |
 | [`server.port`](../attributes-registry/server.md) | int | Server port number. [6] | `80`; `8080`; `443` | Recommended |
 
 **[1]:** The value SHOULD be normalized to lowercase.
 
-**[2]:** `network.protocol.version` refers to the version of the protocol used and might be different from the protocol client's version. If the HTTP client has a version of `0.27.2`, but sends HTTP version `1.1`, this attribute should be set to `1.1`.
+**[2]:** If protocol version is subject to negotiation (for example using [ALPN](https://www.rfc-editor.org/rfc/rfc7301.html)), this attribute SHOULD be set to the negotiated version. If the actual protocol version is not known, this attribute SHOULD NOT be set.
 
 **[3]:** The value SHOULD be normalized to lowercase.
 

docs/general/attributes.md

@@ -164,13 +164,13 @@ if they do not cause breaking changes to HTTP semantic conventions.
 | [`network.peer.address`](../attributes-registry/network.md) | string | Peer address of the network connection - IP address or Unix domain socket name. | `10.1.2.80`; `/tmp/my.sock` | Recommended |
 | [`network.peer.port`](../attributes-registry/network.md) | int | Peer port number of the network connection. | `65123` | Recommended |
 | [`network.protocol.name`](../attributes-registry/network.md) | string | [OSI application layer](https://osi-model.com/application-layer/) or non-OSI equivalent. [1] | `amqp`; `http`; `mqtt` | Recommended |
-| [`network.protocol.version`](../attributes-registry/network.md) | string | Version of the protocol specified in `network.protocol.name`. [2] | `3.1.1` | Recommended |
+| [`network.protocol.version`](../attributes-registry/network.md) | string | The actual version of the protocol used for network communication. [2] | `1.1`; `2` | Recommended |
 | [`network.transport`](../attributes-registry/network.md) | string | [OSI transport layer](https://osi-model.com/transport-layer/) or [inter-process communication method](https://wikipedia.org/wiki/Inter-process_communication). [3] | `tcp`; `udp` | Recommended |
 | [`network.type`](../attributes-registry/network.md) | string | [OSI network layer](https://osi-model.com/network-layer/) or non-OSI equivalent. [4] | `ipv4`; `ipv6` | Recommended |
 
 **[1]:** The value SHOULD be normalized to lowercase.
 
-**[2]:** `network.protocol.version` refers to the version of the protocol used and might be different from the protocol client's version. If the HTTP client has a version of `0.27.2`, but sends HTTP version `1.1`, this attribute should be set to `1.1`.
+**[2]:** If protocol version is subject to negotiation (for example using [ALPN](https://www.rfc-editor.org/rfc/rfc7301.html)), this attribute SHOULD be set to the negotiated version. If the actual protocol version is not known, this attribute SHOULD NOT be set.
 
 **[3]:** The value SHOULD be normalized to lowercase.