In this scenario, a dock door is enabled to read tags,
tags move through the doorway and trip the sensor, and messages are
sent, received, and handled by WebSphere® Premises Server.
IBM® WebSphere Premises Server provides
example code for the following usage scenario. It also provides code
for other usage scenarios, including enhanced dock door receiving.
You can also develop your own agents or modify the example agents,
in which case, you might also need to develop other business logic
on WebSphere Premises Server or
in Data Transformation.
Note: The term, portal, here is
used to indicate a dock door and its associated I/O devices. A portal
is the physical installation that enables the reading of information
when pallets move through it. A portal consists of a reader, antennas,
sensor devices, and feedback devices, such as a light tree. In a retail
dock door receiving scenario, the portal is directly behind a dock
door of a retail store or retail distribution center.
Note: The terms edge controller, Data Capture and Delivery, remote Data Capture and Delivery, and local Data Capture and Delivery all
refer to the same functional concept, and can be used interchangeably
most of the time. These terms refer to the portion of the RFID system
that interfaces directly with the physical readers, collecting the
raw data and performing some basic processing. Starting with the WebSphere RFID Premises Server 6.0
release, this functionality can run as part of the WebSphere Premises Server (local Data Capture and Delivery), or on
a separate processor (remote Data Capture and Delivery) to distribute
load. In previous versions of WebSphere RFID Premises Server, this
functionality running on a remote processor was referred to as an
edge controller. For simplicity and compatibility with previous versions
of the product, the term edge controller is still used in the product
documentation.
The following steps describe the usage scenario:
- By default, the portal is enabled (portal.initial is
set to on in the PortalControllerAgent file).
The I/O agent publishes an event message to the messaging service.
The controller agent that is subscribed to the switch topic registers
the event and publishes a "dock door enabled message" to the messaging
service and then to WebSphere Premises Server.
Note: If
the portal property, portal.initial, is set to off in
the PortalControllerAgent file, or the switch
is ever used, then the switch is required to set the portal back on.
At that point, you would press a switch to enable the portal, and
an I/O agent connected to the switch through an I/O adapter senses
the change.
- A motion sensor is tripped by the movement of an item through
a reader portal.
- The I/O agent connected to this motion sensor notes the change
and publishes a sensor event message to the messaging service.
- The controller agent, also subscribed to the motion sensor topic,
registers the event and publishes a message to the portal reader to
begin reading tags.
- The reader agent receives the message to begin reading, starts
reading, and publishes the found tags to the messaging service.
- After a period of motion sensor inactivity, the controller agent
publishes a message to the reader to stop reading.
- The reader agent receives the tag information from the messaging
service.
- The reader agent removes duplicate reads and any non-pallet tags
from the data.
- A filtered set of tags is published to the messaging service and
then to the WebSphere Premises Server.
- The tag information is received by the Event server application
running on the WebSphere Premises Server.
- The list of tags and the tag reader from which they were retrieved
are sent to the enterprise system to be verified against an excepted
list in the warehouse management system.
- The enterprise responds with an "accept" or "reject" message for
the items in the list.
- The WebSphere Premises Server formats
the response and forwards it to the correct Data Capture and Delivery controller.
- The message is published to the messaging service and is received
by the controller agent.
- If the item was expected, a green light message is published through
the messaging service. If the item was not expected, a red light message
is published.