Proposal for issue MQTT-585 - Session Present Indicator on CONNACK

[Simon Johnson <simon.johnson@u-blox.com>]

Hi all,

Further to request submitted by Patrick Van Bennekom, I have drafted a proposal to include a sessionPresent indicator on a new flags field located at Byte 4 on the CONNACK packet. 

See ticket for full proposal, in summary: A new field with 7 reserved bits for future use and Bit 0 specified as the session present bit. This field will be used by the gateway to indicate whether an existing session was held on the gateway for the given clientId.

I can envisage there being a need for further indicator flags on session behaviour; so this felt like the most future proof approach.

https://issues.oasis-open.org/browse/MQTT-585?filter=16076

Please feel free to feedback and comment on this proposal. If this received no objections at the next meeting, I will endeavour to get this into the work draft ASAP.

Best,

Simon.