diff --git a/src/y-websocket.js b/src/y-websocket.js
index 38465b3..9bb95f2 100644
--- a/src/y-websocket.js
+++ b/src/y-websocket.js
@@ -177,6 +177,7 @@ export class WebsocketProvider extends Observable {
       serverUrl = serverUrl.slice(0, serverUrl.length - 1)
     }
     const encodedParams = url.encodeQueryParams(params)
+    this.bcChannel = serverUrl + '/' + roomname
     this.url = serverUrl + '/' + roomname + (encodedParams.length === 0 ? '' : '?' + encodedParams)
     this.roomname = roomname
     this.doc = doc
@@ -212,7 +213,7 @@ export class WebsocketProvider extends Observable {
       this.mux(() => {
         const encoder = readMessage(this, new Uint8Array(data), false)
         if (encoding.length(encoder) > 1) {
-          bc.publish(this.url, encoding.toUint8Array(encoder))
+          bc.publish(this.bcChannel, encoding.toUint8Array(encoder))
         }
       })
     }
@@ -277,7 +278,7 @@ export class WebsocketProvider extends Observable {
   }
   connectBc () {
     if (!this.bcconnected) {
-      bc.subscribe(this.url, this._bcSubscriber)
+      bc.subscribe(this.bcChannel, this._bcSubscriber)
       this.bcconnected = true
     }
     // send sync step1 to bc
@@ -286,21 +287,21 @@ export class WebsocketProvider extends Observable {
       const encoderSync = encoding.createEncoder()
       encoding.writeVarUint(encoderSync, messageSync)
       syncProtocol.writeSyncStep1(encoderSync, this.doc)
-      bc.publish(this.url, encoding.toUint8Array(encoderSync))
+      bc.publish(this.bcChannel, encoding.toUint8Array(encoderSync))
       // broadcast local state
       const encoderState = encoding.createEncoder()
       encoding.writeVarUint(encoderState, messageSync)
       syncProtocol.writeSyncStep2(encoderState, this.doc)
-      bc.publish(this.url, encoding.toUint8Array(encoderState))
+      bc.publish(this.bcChannel, encoding.toUint8Array(encoderState))
       // write queryAwareness
       const encoderAwarenessQuery = encoding.createEncoder()
       encoding.writeVarUint(encoderAwarenessQuery, messageQueryAwareness)
-      bc.publish(this.url, encoding.toUint8Array(encoderAwarenessQuery))
+      bc.publish(this.bcChannel, encoding.toUint8Array(encoderAwarenessQuery))
       // broadcast local awareness state
       const encoderAwarenessState = encoding.createEncoder()
       encoding.writeVarUint(encoderAwarenessState, messageAwareness)
       encoding.writeVarUint8Array(encoderAwarenessState, awarenessProtocol.encodeAwarenessUpdate(this.awareness, [this.doc.clientID]))
-      bc.publish(this.url, encoding.toUint8Array(encoderAwarenessState))
+      bc.publish(this.bcChannel, encoding.toUint8Array(encoderAwarenessState))
     })
   }
   disconnectBc () {
@@ -310,7 +311,7 @@ export class WebsocketProvider extends Observable {
     encoding.writeVarUint8Array(encoder, awarenessProtocol.encodeAwarenessUpdate(this.awareness, [this.doc.clientID], new Map()))
     broadcastMessage(this, encoding.toUint8Array(encoder))
     if (this.bcconnected) {
-      bc.unsubscribe(this.url, this._bcSubscriber)
+      bc.unsubscribe(this.bcChannel, this._bcSubscriber)
       this.bcconnected = false
     }
   }