---
title: AggregateEvent
slug: jetstream-v3/aggregateevent
docTags:
createdAt: 2024-01-23T15:46:48.708Z
---
## About
AggregateEvent is used to indicate a change in the tag population of a device's read zone. For example, if a tag is removed from a device's read zone, an AggregateEvent message is published with the missing Tag EPCs listed as "Removes". If a tag is added to a device's read zone, an AggregateEvent message is published with the new Tag EPCs listed as "Adds". A single AggregateEvent can include multiple Adds and Removes.
## Fields
| **Property** | **Details** |
| ----------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Type**
string | The type of Jetstream event. |
| **EventId**
string
Unique | The ID assigned to the event. |
| **EventTime**
string | The time that the event occurred.
The value is expressed in UTC.
This value is expressed in the following format: yyyy-MM-ddTHH\:mm\:ssZ |
| **Version**
int | The Jetstream version of the event. |
| **Device**
string | The name of the device. |
| **ReceivedTime**
string | The time that the event was received from the device.
The value is expressed in UTC.
This value is expressed in the following format: yyyy-MM-ddTHH\:mm\:ssZ |
| **Adds**
array(string) | The RFID tag EPC numbers newly introduced to the device's read zone. |
| **Removes**
array(string) | The RFID tag EPC numbers no longer found in the device's read zone. |
| **PassRfid**
string | For secured [RFID Enclosures (Cabinets, Fridges, Freezers)](docId\:uXZf6DdOf1T2zGZzjH9M6), the credential used to open the door.
For devices without secured access, this parameter will be an empty string. |
## Example
### Published AggregateEvent (14 RFID Tag EPCs added, 9 RFID Tag EPCs removed)
:::BlockQuote
\{
"PassRfid": "MyPassNumberOrMyAccessToken",
"Adds": \[
"AD4424044148C57A5C0000B0",
"AD4424044149857D5B0000C4",
"AD4424044148ED765B0000B4",
"AD4424044148E3745C0000B3",
"AD4424044149AF7A5C0000C8",
"AD44240441498F755B0000C5",
"AD44240441497D725A0000C3",
"AD4424044149B9775C0000C9",
"AD442404414973765D0000C2",
"AD442404414973775C0000C1",
"AD4424044149A3795C0000C7",
"AD4424044148D9795C0000B2",
"AD4424044148CD775C0000B1",
"AD4424044149C3765C0000CA"
],
"Removes": \[
"AD4424044149F1765B0000CF",
"AD4424044149FB7B5C0000D0",
"AD4424044149E97A5C0000CE",
"AD442404414A0F7B5C0000D2",
"AD4424044149D57A5C0000CC",
"AD4424044149DF795C0000CD",
"AD442404414A057B5C0000D1",
"AD4424044149CB775C0000CB",
"AD442404414A19765C0000D3"
],
"Device": "MyDeviceName",
"ReceivedTime": "2018-05-19T13:23:44Z",
"Type": "AggregateEvent",
"EventId": "a85745f7-a348-4454-8a97-8eee2aeef853",
"EventTime": "2018-05-19T13:23:36Z",
"Version":2
}
:::
## Version Changes
Addition of the Version property