[AMQ-6345] [MQTT] ping response without CONNECT

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 5.13.3
• Fix Version/s: 5.13.4, 5.14.0
• Component/s: MQTT

Environment

Ubuntu Linux 14.04

• Assignee: Christopher L. Shannon
• Reporter: Martin Tappler
• Created: 04/Jul/16 14:07
• Updated: 07/Jul/16 18:26
• Resolved: 06/Jul/16 16:03

Description

I am currently investigating the behavior of several MQTT brokers and noticed that the ActiveMQ broker responds to PINGREQ packets with PINGRESP packets even if no CONNECT packet has been sent before.

This would be a violation of MQTT-3.1.0-1 and MQTT-4.8.0-1 of MQTT v3.1.1 while MQTT v3.1 is not that strict about this issue, but does also state "When a TCP/IP socket connection is established from a client to a server, a protocol level session must be created using a CONNECT flow." (http://public.dhe.ibm.com/software/dw/webservices/ws-mqtt/mqtt-v3r1.html#connect)

Since ActiveMQ supports MQTT v3.1 according to http://activemq.apache.org/,
but also MQTT v3.1.1 according to Issue AMQ-4990, I am not sure whether this should actually be considered a bug.