Enable the WebSocket feature in DCDN so that your origin server can handle ws:// or wss:// requests for real-time data transmission and updates.
Background
WebSocket is a TCP-based protocol that provides persistent, full-duplex communication between a client and a server, allowing the server to push data to the client at any time. Before WebSocket, two-way communication required continuous HTTP polling, which was inefficient and resource-intensive. With WebSocket, a single handshake establishes a persistent connection for bidirectional data transfer, saving server resources and bandwidth.
Use cases
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Scenario |
Description |
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Bullet comments |
When a user sends a bullet comment, the server displays it on their screen along with comments from other users in real time. |
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Online education |
In a one-to-many online class, the teacher's notes and outlines are pushed to multiple students' clients in real time. |
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Real-time quotes for financial products |
Prices for stocks, gold, and other assets change rapidly. WebSocket pushes these updates to clients worldwide in real time, helping traders make quick decisions. |
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Live sports updates |
Millions of fans follow live sports events. WebSocket delivers real-time score and event updates for a smooth viewing experience. |
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Video conferencing and chat |
Video conferencing and chat applications require real-time data exchange between participants. WebSocket enables this continuous communication. |
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Location-based applications |
Many applications use mobile GPS capabilities. If your app tracks a user's location continuously, for example, to record a running route, WebSocket lets you collect detailed position data in real time. |
Considerations
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The WebSocket protocol is not compatible with the Configure HTTP/2 feature. To prevent access errors for your domain name, do not enable both features at the same time.
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WebSocket is for dynamic acceleration only, and your origin server must also support it.
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If you upgraded your domain name from CDN to DCDN, you cannot enable the WebSocket feature directly. You must first fill out a form to request an architecture change for your domain name.
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WebSocket traffic is billed separately. For more information, see WebSocket Billing.
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To adjust the WebSocket connection timeout, configure the Origin request timeout feature.
Configure WebSocket
Before you configure WebSocket, ensure you have disabled the Configure HTTP/2 feature and enabled Dynamic Acceleration.
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Log on to the DCDN console.
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In the left-side navigation pane, click Domain Names.
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On the Domain Names page, find the domain name that you want to manage and click Configure in the Actions column.
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In the left-side navigation pane for the domain name, click WebSocket and turn on the WebSocket switch.
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Click Modify.
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In the Configure WebSocket dialog box, configure the Connection Timeout Period and Back-to-Origin Protocol.
Parameter
Description
Connection Timeout Period
The timeout period for a WebSocket connection on the DCDN platform. If no data is transmitted within this period, DCDN closes the connection.
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Default value: 60.
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Unit: seconds.
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Recommended configuration: A <= B <= C.
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A: Client connection timeout.
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B: DCDN platform connection timeout.
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C: Origin server connection timeout.
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Back-to-Origin Protocol
The protocol that DCDN uses to request resources from your origin server.
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Follow: The origin request protocol matches the client request protocol (HTTP or HTTPS). Your origin server must support port 80 or 443.
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HTTP: DCDN uses HTTP for origin requests.
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HTTPS: DCDN uses HTTPS for origin requests. Your origin server must support port 443.
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Click OK.