---
schema_version: "1"
id: 0721c6e41641b25186159e6002065f41f226cb8fa04a515a5fd89b3253562810
title: Server-Sent Events for Real-Time Messaging
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/service/264-0-0/miaw_sse_for_real_time_messaging.md
canonical_url: https://help.salesforce.com/s/articleView?id=service.miaw_sse_for_real_time_messaging.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: f06e7b9f716213682458181f767daebdb8aba39da20fe9d36f99aada107dc03d
description: Understand how our platform uses Server-Sent Events (SSE) to push data directly to a user's browser in real time. Learn why network security tools sometimes flag and block SSE connections.
products:
  - Service Cloud
  - Digital Engagement
release: "264"
---
# Server-Sent Events for Real-Time Messaging

Understand how our platform uses Server-Sent Events (SSE) to push data directly to a user's browser in real time. Learn why network security tools sometimes flag and block SSE connections.

### Required Editions

[View Supported Editions](https://help.salesforce.com/s/articleView?id=service.messaging_editions.htm&type=5&language=en_US)

<table class="slds-table slds-table_bordered slds-max-medium-table_stacked slds-m-bottom_small permission">
      <colgroup>
        <col style="width:50%">
        <col style="width:50%">
      </colgroup>
      <thead class="slds-text-title_caps ">
        <tr class="">
          <th scope="colgroup" class="slds-cell-wrap" colspan="2" style="text-align:center;vertical-align:top;" id="d26676e41">User Permissions</th>
        </tr>
      </thead>
      <tbody>
        <tr class="">
          <td data-label="User Permissions" class="slds-cell-wrap" style="vertical-align:top;" headers="d26676e41 ">To manage connections and handle messaging sessions:</td>

          <td class="slds-cell-wrap" style="vertical-align:top;" headers="d26676e41 ">
            <ul>
              <li>Enhaced Chat User permission set</li>

              <li>Enhanced Chat Rep user permission</li>

            </ul>
          </td>

        </tr>
        <tr class="">
          <td data-label="User Permissions" class="slds-cell-wrap" style="vertical-align:top;" headers="d26676e41 ">To reply or transfer conversations:</td>

          <td class="slds-cell-wrap" style="vertical-align:top;" headers="d26676e41 ">Access Conversation Entries permission. This permission is available via the
            Service Cloud Voice User license or the Agentforce Service Agent User license.</td>

        </tr>
      </tbody>
    </table>

Unlike traditional polling, where a browser constantly asks for updates, SSE keeps a single open line for instant delivery.

  
| Feature | polling | SSE |
| --- | --- | --- |
| Connection | Short-lived, frequent | Long-lived, single connection |
| Efficiency | Low (high overhead) | High (low overhead) |
| Latency | Delayed | Instant (real-time) |

## Why Network Security Blocks SSE

Because SSE connections stay open indefinitely, security tools designed for stop-and-start web traffic often flag them. Common failure points include:

- **SSL and TLS inspection**: Security engines sometimes buffer the stream to scan for viruses. Because the stream never ends, the data is held indefinitely and never reaches the user.
- **Proxy buffering**: Proxies waiting for a full file never see one, which causes the application to freeze.
- **Connection timeouts**: Firewalls sometimes kill the connection if they deem it idle during quiet periods.

- **[Configure Your Network for Server-Sent Events](https://help.salesforce.com/s/articleView?id=service.configure_server_sent_events.htm&release=264.0.0&type=5)**  
    Make sure that your real-time messaging services have stable connectivity by configuring your IT and network security settings.