diff --git a/src/core/pipe.js b/src/core/pipe.js
index d7c4139..2835a50 100644
--- a/src/core/pipe.js
+++ b/src/core/pipe.js
@@ -1,6 +1,6 @@
 import EventEmitter from 'events';
 import {MIDDLEWARE_DIRECTION_UPWARD} from './middleware';
-import {PRESET_INIT, PRESET_FAILED} from '../presets/defs';
+import {PRESET_FAILED} from '../presets/defs';
 
 export class Pipe extends EventEmitter {
 
@@ -49,8 +49,6 @@ export class Pipe extends EventEmitter {
     }
     this._upstream_middlewares = middlewares;
     this._downstream_middlewares = [].concat(middlewares).reverse();
-    // initial broadcast
-    this.broadcast('pipe', {type: PRESET_INIT});
   }
 
   getMiddlewares(direction = MIDDLEWARE_DIRECTION_UPWARD) {
diff --git a/src/presets/defs.js b/src/presets/defs.js
index d8fcc36..3255656 100644
--- a/src/presets/defs.js
+++ b/src/presets/defs.js
@@ -2,8 +2,6 @@
 
 // - pushed by relay
 
-export const PRESET_INIT = '@action:preset_init';
-
 /**
  *  {
  *    type: CONNECTION_CREATED,
@@ -70,15 +68,30 @@ export const PRESET_PAUSE_SEND = '@action:preset_pause_send';
 export const PRESET_RESUME_RECV = '@action:preset_resume_recv';
 export const PRESET_RESUME_SEND = '@action:preset_resume_send';
 
+/**
+ *
+ * @lifecycle
+ *   [static checkParams() -> static onInit()] -> constructor() -> ... -> onDestroy()
+ *                Only call once
+ */
 export class IPreset {
 
   /**
    * check params passed to the preset, if any errors, should throw directly
+   * @param params
    */
   static checkParams(params) {
 
   }
 
+  /**
+   * you can make some cache in this function
+   * @param params
+   */
+  static onInit(params) {
+
+  }
+
   // callbacks
 
   /**