Data Services for RFID – Enabling Edge Managed Tag Reading from the Cloud
In April, Zebra Data Services announced the first fully cloud-based offering for fixed RFID. Along with the ability to manage readers and get tag read data to the cloud, we introduced the concept of Read Modes. This post will detail Read Modes - what they are and how and when to use them.
Read Modes can be thought of in several ways, but at heart they are designed to limit the internet traffic coming from the RFID readers to the cloud, yet still enable near-real-time RFID reading for many use cases. Normally a reader will detect a tag in the vicinity of an antenna multiple times a second. If all those tags were sent to the cloud, it would cause issues with the local network as well as the servers to handle the traffic. Read Modes are processed and handled within the OS of the readers. They allow you to filter out tag reads you don’t care about and only send notifications when you need it to. The read modes that we currently offer may not cover all use cases, but we believe they cover most. Future updates will likely include additional methods to set up read modes to meet additional specific needs.
Currently we offer 3 main read modes: Simple, Inventory, and Portal modes. You can set up different modes by reader or antenna, so a single reader can function in multiple locations and use cases. You can set blocking/allowing filters on each antenna as well so you can ignore specific types of tags. You may only want to notify the system if it detects tag with specific prefix values or with rssi values over or under specific thresholds. Once the tag events are in the cloud, there are many more filters that can be applied, and we will cover those in a later post.
Simple Mode
Simple mode is used when you want to be notified the first time a reader detects a tag, but don’t care about how long it stays in an area or if it sees it again. A good use case for this is on dock doors where you want to know when you are loading or unloading a truck. Another use case is sometimes on distribution or assembly lines to ensure the products are passing through the right places to fulfil orders. Any time a product is moving through an area and you want to detect that it has passed checkpoints without having anything trigger it.
Setting up read modes is simple. You can use the Device Management for RFID API /mode configuration. An example of a set read mode to Simple on antenna 1 with antenna power set to 10 (low):
curl -X PUT \
https://api.zebra.com/v2/devices/readers/FX7500XXXXXX/mode \
-H 'Content-Type: application/json' \
-H 'apikey: XXXXXX' \
-H 'cache-control: no-cache' \
-d '{
"antennas": [
1
],
"mode": "simple",
"transmitPower": 10
}'Inventory Mode
If you want to take inventory of a location, then you use Inventory mode. This will set up the reader to notify you of tags it’s detecting in a location on a scheduled timing. If you have product that doesn’t move around a lot, such as a warehouse, you could set the inventory to trigger once per day or per hour. It would then send a notification for each tag detected once per hour. This service is also useful for detecting presence for internal tracking use cases, such as medications moving around a hospital or employees in an office where you want to know where something is now or where it has gone. You would need to set the scheduled detection to be much shorter, which does increase the traffic through the infrastructure and services, so there is a downside to using it this way. With Inventory Mode, a tag can be detected and notifications sent multiple times. The events that are transmitted will also tell you how many times in the interval, the reader actually detected the tag.
An example of setting up an hourly inventory using the Device Management for RFID API /mode configuration. This will set antennas 2 and 3 to have maximum range and send tags it sees hourly.
curl -X PUT \
https://api.zebra.com/v2/devices/readers/FX7500XXXXXX/mode \
-H 'Content-Type: application/json' \
-H 'apikey: XXXXXX \
-H 'cache-control: no-cache' \
-d '{
"antennas": [
2,3
],
"interval": {
"unit": "minutes",
"value": 60
},
"mode": "inventory",
"transmitPower": 30
}'Portal Mode
This mode is set up to use the GPIO input on the reader to trigger taking an inventory of tags and sending notifications. A tag can be alerted on multiple times as long as it is in detectable range every time the GPI is triggered. The primary use case for this is in automatic doors that can trigger the reader so a company can detect products entering or leaving a location through the doors. This also can be used in combination with any number of environmental sensors, from temperature to light beams. There are many use cases, but one example is say a temperature sensor will trigger the port if the temperature rises above 0 in a refrigerator. The system can automatically take inventory of the effected products so they can recall/replace them due to safety factors.
The Portal mode setup is slightly more complicated as you have to tell it what port you want to have triggering the read as well as well as how long you want to read for to detect the local tags. The setup below will detect for 3 seconds after being triggered and send events for each tag it detects in that time.
curl -X PUT \
https://api.zebra.com/v2/devices/readers/FX7500XXXXXX/mode \
-H 'Content-Type: application/json' \
-H 'apikey: XXXXXX \
-H 'cache-control: no-cache' \
-d '{
"antennas": [
1
],
"mode": "portal",
"startTrigger": {
"port": 1,
"signal": "LOW"
},
"stopInterval": 3,
"transmitPower": 10
}'
You capture the notification events from these read modes using webhooks setup with the Event Subscription Service or later using the Analytics and Reporting Query. We will go into more detail on these services in future posts.
If you are interested in full demo access to Zebra Data Services for RFID or purchasing, please contact your Zebra Account Team or Purchasing Partner.
Zebra Data Services
Robin West