Remove lines 430-431 in Chapter 2 , which deal with protocol violations. Add terminology definitions; Protocol Violation: A Control Packet that is not constructed or flowed in a way which conforms to this specification. Transient Error: A transient error is an error which may not re occur if the action that caused it is repeated. Non Normative comment. For example, an authorization failure of a PUBLISH Packet might not re occur the next time a similar PUBLISH Packet is received, if the administrator has authorized the client to make the publication in the mean time. Rewrite Section 4.8 line 1557 on as follows: 4.8 Handling errors. Unless stated otherwise, if either the Server or Client encounters a Protocol Violation, it MUST close the Network Connection on which it received that Control Packet which caused the Protocol Violation. [MQTT-4.8.0-1] . If the Client or Server encounters a Transient Error while processing an inbound Control Packet it MUST close the Network Connection on which it received that Control Packet [MQTT-4.8.0-2] . If a Server detects a transient error it SHOULD NOT disconnect or have any other affect on its interactions with any other Client.