1. MQTT JIRA – 324 Consolidate list of optional server capabilities and review how they are signaled to the client
Rahul Gupta

2. List of optional capabilities in CONNECT Control Packet
Session Expiry Interval
Will Delay Interval
Receive Maximum
Topic Alias Maximum
Maximum Packet Size
Request Reply Info
Request Problem Info
User Property
Auth Method
Auth Data

3. List of optional capabilities in CONNACK Control Packet
Session Present
Receive Maximum
Maximum Packet Size
Maximum QoS
Retain unavailable
Assigned Client Identifier
Topic Alias Maximum
Server Keep Alive
Reply Info
Server Reference
Auth Method
Auth Data
Reason String

4. List of optional capabilities in PUBLISH Control Packet
Payload format indicator
Publication expiry interval
Topic Alias
Reply Topic
Correlation Data
Subscription Identifier
User Property
Reason String

5. List of optional capabilities in SUBSCRIBE Control Packet
Subscription Identifier
Subscription Option – No Local
Subscription Option – Retain Handling
Subscription Option – Retain as Published

6. List of optional capabilities in PUBACK, PUBREC, PUBREL, PUBCOMP, SUBACK and UNSUBACK Control Packet
Reason String

7. List of optional capabilities in DISCONNECT Control Packet
Session Expiry Interval
Server Reference
Reason String

8. Optional Capability Map

9. Optional Capabilities between Server and Client