---
schema_version: "1"
id: 903e1f02bdc4e7e247cce9c4bcc4ecb696b27dae87b7f4cf195175129f469588
title: HTTP/2 Support
collection: mulesoft
version: current
locale: en-us
portal_url: https://docs.salesforce.com/mulesoft/current/en-us/http-connector/latest/http-2-support.md
canonical_url: https://docs.mulesoft.com/http-connector/latest/http-2-support
source_site: docs.mulesoft.com
content_type: documentation
content_hash: 9d58be50f1892d8f4ff02318ebbafd7e0be8ce7518154df0ffae487da97eda1f
description: MuleSoft Documentation Site
release: "1.12"
latest: true
---
---
product: HTTP Connector
version: 1.12
is-latest-version: true
---

# HTTP/2 Support

> For the full documentation index, see: https://docs.mulesoft.com/llms.txt

Get faster, more efficient, and secure communication in Mule apps with HTTP/2 support in HTTP
Connector.

HTTP/2 is the second major version of the Hypertext Transfer Protocol, the foundation of
communication for the World Wide Web. Published as RFC 7540, HTTP/2 addresses the performance
limitations of HTTP/1.1 by improving speed, efficiency, and security.

> [!NOTE] HTTP/2 features in Mule runtime 4.10.0 and later are in early availability and subject to
> change.

## Before You Begin

To use this feature, you must have:

- Mule runtime 4.10.0 or later

- HTTP Connector version 1.11.0 or later

- The `mule.http.service.implementation=NETTY` system property set

- Runtime Fabric or a Hybrid Standalone environment

> [!IMPORTANT] HTTP/2 support is available only on Anypoint Runtime Fabric and Hybrid Standalone
> environments.

## Key Features

HTTP/2 support improves performance with these capabilities:

- **Multiplexing**

  Sends multiple requests and responses over a single TCP connection at the same time, avoiding
  HTTP/1.1 head-of-line blocking and reducing latency.

- **Header Compression (HPACK)**

  Compresses request and response headers to reduce data transfer size and speed up load times.

- **Binary Protocol**

  Uses binary framing instead of text representation for more efficient communication.

## Backward Compatibility

- Apps that work with HTTP/1 continue to work without changes. If you don’t modify the connector
  configuration, HTTP/1.1 remains the default protocol.

- Autogenerated API proxies continue to use HTTP/1.1 unless you customize the proxy configuration to
  enable HTTP/2.

## Wire Logging

Wire logging uses the same configuration as HTTP/1.1. Because HTTP/2 is a binary protocol, log
output looks different:

```xml
<AsyncLogger name="org.mule.service.http.impl.service.HttpMessageLogger" level="DEBUG" />
```

### Example: HTTP/2 Wire Logging Output

When HTTP/2 wire logging is enabled, Mule logs both the binary frames exchanged between the client
and server and the decoded data for readability. Because HTTP/2 is a binary protocol, the output
includes hexadecimal representations of each frame.

```log
DEBUG [http.listener.08] org.mule.service.http.impl.service.HttpMessageLogger.h2ListenerConfig: [6b24f7f9, L:/127.0.0.1:8081 - R:/127.0.0.1:57672] READ: 117B
         +-------------------------------------------------+
|00000000| 50 52 49 20 2a 20 48 54 54 50 2f 32 2e 30 0d 0a |PRI * HTTP/2.0..|
|00000010| 0d 0a 53 4d 0d 0a 0d 0a ...                     |..SM...          |
DEBUG [http.listener.08] org.mule.service.http.impl.service.HttpMessageLogger.h2ListenerConfig: WRITE: 36B
|00000000| 52 65 71 75 65 73 74 20 70 72 6f 74 6f 63 6f 6c |Request protocol|
|00000010| 20 76 65 72 73 69 6f 6e 20 77 61 73 3a 20 48 54 | version was: HT|
|00000020| 54 50 2f 32                                     |TP/2            |
```

The log shows these details:

- The `PRI * HTTP/2.0` connection preface sent by the client.

- Binary frame content in hexadecimal form.

- Mule’s decoded payload returned to the client (`Request protocol version was: HTTP/2`).

- `READ` entries correspond to inbound frames, and `WRITE` entries are outbound frames.

## Configuration Structure

Enable HTTP/2 support by adding the `<http:protocol-support>` element to your connection
configuration. You can enable or disable HTTP/1.1 and HTTP/2 independently with this element.

### Basic Configuration Example

Use this configuration to enable both HTTP/1.1 and HTTP/2 support on the same listener connection.

```xml
<http:listener-config name="http2Config">
    <http:listener-connection host="0.0.0.0" port="8081" protocol="HTTPS">
        <tls:context>
            <!-- TLS configuration -->
        </tls:context>
        <http:protocol-support>
            <http:http1-support enable="true" />
            <http:http2-support enable="true" />
        </http:protocol-support>
    </http:listener-connection>
</http:listener-config>
```

### HTTP/2 Configuration Parameters

The `<http:http2-support>` element supports these parameters:

<table><colgroup><col> <col> <col> <col> <col></colgroup><thead><tr><th>Parameter</th><th>Type</th><th>Default</th><th>Range</th><th>Description</th></tr></thead><tbody><tr><td><p><code>enable</code></p></td><td><p>Boolean</p></td><td><p><code>true</code></p></td><td><p>-</p></td><td><p>Enables or disables HTTP/2 support.</p></td></tr><tr><td><p><code>headerTableSize</code></p></td><td><p>Long</p></td><td><p>4096</p></td><td><p>0 - 4,294,967,295</p></td><td><p>Maximum size of header compression table in octets.</p></td></tr><tr><td><p><code>maxConcurrentStreams</code></p></td><td><p>Long</p></td><td><p>No limit</p></td><td><p>100 - 4,294,967,295</p></td><td><p>Maximum number of concurrent streams.</p></td></tr><tr><td><p><code>initialWindowSize</code></p></td><td><p>Integer</p></td><td><p>65535</p></td><td><p>0 - 2,147,483,647</p></td><td><p>Initial flow-control window size in octets.</p></td></tr><tr><td><p><code>maxFrameSize</code></p></td><td><p>Integer</p></td><td><p>16384</p></td><td><p>16,384 - 16,777,215</p></td><td><p>Maximum frame payload size in octets.</p></td></tr><tr><td><p><code>maxHeaderListSize</code></p></td><td><p>Long</p></td><td><p>8192</p></td><td><p>0 - 4,294,967,295</p></td><td><p>Maximum header list size in octets.</p></td></tr></tbody></table>

### Configuration Examples

These examples show how to enable and configure HTTP/2 support in different scenarios.

#### Basic HTTP/2 with SSL (Recommended)

Use this configuration to enable HTTP/2 over HTTPS with TLS for secure communication.

```xml
<http:listener-config name="h2ListenerConfig">
    <http:listener-connection host="0.0.0.0" port="8443" protocol="HTTPS">
        <tls:context>
            <tls:trust-store path="cacerts.jks" password="changeit" type="JKS"/>
            <tls:key-store path="keystore.jks" keyPassword="changeit" password="changeit" type="JKS"/>
        </tls:context>
        <http:protocol-support>
            <http:http1-support />
            <http:http2-support />
        </http:protocol-support>
    </http:listener-connection>
</http:listener-config>

<http:request-config name="h2RequestConfig">
    <http:request-connection host="localhost" port="8443" protocol="HTTPS">
        <tls:context>
            <tls:trust-store path="cacerts.jks" password="changeit" type="JKS"/>
            <tls:key-store path="keystore.jks" keyPassword="changeit" password="changeit" type="JKS"/>
        </tls:context>
        <http:protocol-support>
            <http:http2-support />
        </http:protocol-support>
    </http:request-connection>
</http:request-config>
```

When using SSL, TLS negotiates which HTTP version to use through the
[ALPN extension](https://datatracker.ietf.org/doc/html/rfc7301#section-3).

#### HTTP/2 Cleartext (H2C) with Upgrade

Use this configuration to enable HTTP/2 support with cleartext on the listener connection.

```xml
<http:listener-config name="h2cListenerConfig">
    <http:listener-connection host="0.0.0.0" port="8080" protocol="HTTP">
        <http:protocol-support>
            <http:http1-support />
            <http:http2-support />
        </http:protocol-support>
    </http:listener-connection>
</http:listener-config>

<http:request-config name="h2cRequestConfig">
    <http:request-connection host="localhost" port="8080">
        <http:protocol-support>
            <http:http1-support />
            <http:http2-support />
        </http:protocol-support>
    </http:request-connection>
</http:request-config>
```

#### HTTP/2 Cleartext with Prior Knowledge (H2C Prior Knowledge)

This configuration shows how to enable HTTP/2 on a server without HTTP/1 support, allowing HTTP
clients to use HTTP/2 with prior knowledge.

```xml
<http:listener-config name="h2cPKListenerConfig">
    <http:listener-connection host="0.0.0.0" port="8080" protocol="HTTP">
        <http:protocol-support>
            <http:http1-support enable="false" />
            <http:http2-support />
        </http:protocol-support>
    </http:listener-connection>
</http:listener-config>

<http:request-config name="h2cPKRequestConfig">
    <http:request-connection host="localhost" port="8080">
        <http:protocol-support>
            <http:http1-support enable="false" />
            <http:http2-support />
        </http:protocol-support>
    </http:request-connection>
</http:request-config>
```

When you enable only HTTP/2 on the server, HTTP clients can send only HTTP/2 requests with prior
knowledge. An HTTP/1 request with “Upgrade: h2c” header is rejected by that server.

#### Fully Parameterized HTTP/2 Configuration

This example shows all configurable HTTP/2 parameters, including recommended values from the HTTP/2
specification.

```xml
<http:listener-config name="h2AllParamsListenerConfig">
    <http:listener-connection host="0.0.0.0" port="8443" protocol="HTTPS">
        <tls:context>
            <tls:trust-store path="cacerts.jks" password="changeit" type="JKS"/>
            <tls:key-store path="keystore.jks" keyPassword="changeit"
                           password="changeit" type="JKS"/>
        </tls:context>
        <http:protocol-support>
            <http:http1-support enable="true" />
            <http:http2-support enable="true"
                                headerTableSize="8192"
                                maxConcurrentStreams="100"
                                initialWindowSize="65535"
                                maxFrameSize="17000"
                                maxHeaderListSize="8192" />
        </http:protocol-support>
    </http:listener-connection>
</http:listener-config>
```

These parameters configure HTTP/2 support and use recommended values from the
[HTTP/2 Settings](https://datatracker.ietf.org/doc/html/rfc9113#SETTINGS).

### Protocol Detection in Flows

You can detect which HTTP version a request used by checking `attributes.version`:

```xml
<flow name="protocolDetectionFlow">
    <http:listener path="/*" config-ref="h2ListenerConfig"/>
    <set-payload value="#['Request protocol version was: ' ++ attributes.version]" />
</flow>
```

This flow can return:

- `Request protocol version was: HTTP/2`

- `Request protocol version was: HTTP/1.1`

## Configuration Guidelines

These guidelines help you configure HTTP/2 settings for compatibility, security, and performance.

### Protocol Compatibility

Use HTTP/2 with SSL whenever possible. The server negotiates the protocol using ALPN (H2 or
HTTP/1.1).

### Parameter Tuning

HTTP/2 settings are recommendations to the implementation and aren’t guaranteed to be honored.

### Security

Use SSL to secure communications.

### Validation Rules

The connector validates HTTP/2 parameters according to RFC 7540:

- `headerTableSize`: 0 - 4,294,967,295

- `maxConcurrentStreams`: 100 - 4,294,967,295 (minimum recommended: 100)

- `initialWindowSize`: 0 - 2,147,483,647

- `maxFrameSize`: 16,384 - 16,777,215

- `maxHeaderListSize`: 0 - 4,294,967,295

## Troubleshooting

Common issues and solutions:

- HTTP/2 not working

  Confirm Mule runtime 4.10.0+ and HTTP Connector 1.11.0+ are installed.

- Connection failures

  Verify TLS configuration for HTTPS connections.

- Parameter validation errors

  Ensure parameter values are within the supported ranges.

- Protocol negotiation failures

  Make sure the client and server both support the same protocols.

### Testing HTTP/2 Configuration

Use this MUnit test to confirm HTTP/2 is working:

```xml
<munit:test name="http2VerificationTest">
    <munit:execution>
        <http:request config-ref="h2RequestConfig" path="/test" />
    </munit:execution>
    <munit:validation>
        <munit-tools:assert-that expression="#[payload]"
            is="#[MunitTools::containsString('HTTP/2')]" />
    </munit:validation>
</munit:test>
```

## See Also

- [Introduction to Anypoint Connectors](https://docs.mulesoft.com/connectors/introduction/introduction-to-anypoint-connectors)

- [HTTP Connector Reference](https://docs.mulesoft.com/http-connector/latest/http-documentation)

- [Salesforce Help](https://help.salesforce.com)