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Author: xingsy97

articles/azure-web-pubsub/concept-service-internals.md

@@ -29,7 +29,7 @@ Azure Web PubSub Service provides an easy way to publish/subscribe messages usin
 
 Workflow as shown in the above graph:
 
-1. A _client_ connects to the service `/client` endpoint using WebSocket transport. Service forwards every WebSocket frame to the configured upstream(server) in the default mode 'sendEvent'. The WebSocket connection can connect with any custom subprotocol for the server to handle, or it can connect with the service-supported subprotocol `json.webpubsub.azure.v1`, which empowers the clients to do pub/sub directly. The other mode of simple WebSocket client `sendToGroup` empowers the clients to do publishing directly. Details are described in [client protocol](#client-protocol).
+1. A _client_ connects to the service `/client` endpoint using WebSocket transport. Service forwards every WebSocket frame to the configured upstream(server) by default, the WebSocket connection can connect with any custom subprotocol for the server to handle. Alternatively, the client could connect with mode `sendToGroup` and send every WebSocket frame to a specific group. The client could also connect with [the service-supported subprotocols](#the-pubsub-websocket-client), which offer features such as sending events to your upstream, joining groups, and directly sending messages to groups. Details are described in [client protocol](#client-protocol).
 2. On different client events, the service invokes the server using **CloudEvents protocol**. [**CloudEvents**](https://github.com/cloudevents/spec/tree/v1.0.1) is a standardized and protocol-agnostic definition of the structure and metadata description of events hosted by the Cloud Native Computing Foundation (CNCF). Detailed implementation of CloudEvents protocol relies on the server role, described in [server protocol](#server-protocol).
 3. The Web PubSub server can invoke the service using the REST API to send messages to clients or to manage the connected clients. Details are described in [server protocol](#server-protocol)