Negotiated options between the client and broker.
UInt16 ClientKeepAlive: Client set keep-alive time in seconds.
UInt32 ClientMaximumPacketSize: Maximum Packet Size the Client is willing to accept
UInt16 ClientReceiveMaximum: The Client uses this value to limit the number of QoS 1 and QoS 2 publications that it is willing to process concurrently. There is no mechanism to limit the QoS 0 publications that the Server might try to send. The value of Receive Maximum applies only to the current Network Connection. If the Receive Maximum value is absent then its value defaults to 65,535.
ServerOptions: It’s available only after the State is changed to Connected!