AT-OCS-900N
46
Topic
Enter the topic in this field.
QoS
Click this field to select the Quality of Service (QoS) value.
Configuration and Management Interfaces
Username
Enter the user name for the broker in this field.
Password
Enter the required password in this field.
Authentication
Click this checkbox to toggle between enabling and disabling authentication. If the checkbox is checked, then this
feature is enabled.
QoS Setting
Description
0
At most once
- Guarantees a best-effort delivery. It functions similar to the
UDP protocol, where there is no guarantee of delivery from the client to the
broker. The recipient does not acknowledge receipt of the message and the
message is not stored and re-transmitted by the sender.
1
At least once
- Guarantees that a message is delivered at least once to the
receiver. The sender stores the message until it receives a
PUBACK
packet from
the receiver that acknowledges receipt of the message.
2
Exactly once
- The highest level of service and guarantees that each message
is received only once by the intended recipients. The guarantee is provided by
at least two request/responses between the sender and the receiver.
The
Last Will Settings
, more commonly referred to as
Last Will and Testament (LWT)
, is provided to notify other
clients about a client that experiences an abrupt disconnection. When a client connects to a broker, it can
communication its last will message to the broker. The broker will retain this message until a client has disconnected
“ungracefully”.
Message
Enter the message in this field.
