MQTT feature support in MQTT broker
MQTT broker currently supports the following MQTT features and control packets.
Feature or control packet | MQTT v3.1.1 | MQTT v5 |
---|---|---|
CONNECT Keep-Alive | Supported | Supported |
CONNECT Will Messages | Supported | Supported |
CONNECT Will Messages Delay | N/A | Supported |
CONNECT Will Messages Expiry Interval | N/A | Supported |
CONNECT Will Messages User Properties | N/A | Supported |
CONNECT Clean Start | Supported | Supported |
CONNECT Persistent session | Supported | Supported |
CONNECT Session Expiry Interval | N/A | Supported |
CONNECT Client Receive Maximum | N/A | Supported |
CONNECT Client Maximum Packet Size | N/A | Not Supported |
CONNECT Topic Alias Maximum | N/A | Not Supported |
CONNECT Request Response Information | N/A | Not Supported |
CONNECT User Properties | N/A | Supported |
CONNECT Authentication Data | N/A | Supported |
CONNECT Authentication Method | N/A | Supported |
CONNECT Server Generated Client ID | N/A | Supported |
CONNACK Session Present | Supported | Supported |
CONNACK Server Maximum Packet Size (Server sets maximum allowed incoming packet size based on the memory profile) |
N/A | Supported |
AUTH | N/A | Supported |
PUBLISH QoS0 Delivery | Supported | Supported |
PUBLISH QoS1 Delivery | Supported | Supported |
PUBLISH QoS2 Delivery | Not Supported | Not Supported |
PUBLISH QoS0 Offline messages for persistent sessions (QoS0 messages are dropped for offline sessions) |
Not Supported | Not Supported |
PUBLISH QoS1 Offline messages for persistent sessions | Supported | Supported |
PUBLISH QoS1 Flow control (The broker sends out as many publishes as possible without waiting up to the client's Receive Maximum) |
N/A | Supported |
PUBLISH Retain flag | Supported | Supported |
PUBLISH Correlation Data | N/A | Supported |
PUBLISH Response Topic | N/A | Supported |
PUBLISH Payload Format Indicator | N/A | Supported |
PUBLISH Message Expiry Interval | N/A | Supported |
PUBLISH Topic Alias | N/A | Not Supported |
PUBLISH User Properties | N/A | Supported |
SUBSCRIBE | Supported | Supported |
SUBSCRIBE Retain as Published | N/A | Supported |
SUBSCRIBE Retain Handling | N/A | Supported |
SUBSCRIBE Wildcards | Supported | Supported |
SUBSCRIBE No Local | N/A | Supported |
UNSUBSCRIBE | Supported | Supported |
SUBSCRIBE $SYS topics | Not Supported | Not Supported |
SUBSCRIBE Subscription Identifiers | N/A | Not Supported |
SUBSCRIBE Shared Subscriptions | Supported | Supported |
SUBSCRIBE Max subscriptions per client | Not Supported | Not Supported |
PINGREQ | Supported | Supported |
DISCONNECT | Supported | Supported |
DISCONNECT Session Expiry Interval | N/A | Supported |