diff --git a/src/user/AppBase.sol b/src/user/AppBase.sol
index 9d2e7f4..a102a23 100644
--- a/src/user/AppBase.sol
+++ b/src/user/AppBase.sol
@@ -19,11 +19,10 @@ pragma solidity ^0.8.17;
 
 // https://eips.ethereum.org/EIPS/eip-5164
 abstract contract AppBase {
-    function ormpSender() public view virtual returns (address);
-    function ormpRecver() public view virtual returns (address);
+    function protocol() public view virtual returns (address);
 
-    modifier onlyORMPRecver() {
-        require(ormpRecver() == msg.sender, "!ormp-recver");
+    modifier onlyORMP() {
+        require(protocol() == msg.sender, "!ormp-recver");
         _;
     }
 
diff --git a/src/user/Application.sol b/src/user/Application.sol
index 101a191..458e470 100644
--- a/src/user/Application.sol
+++ b/src/user/Application.sol
@@ -27,15 +27,11 @@ abstract contract Application is AppBase {
         _ORMP = ormp;
     }
 
-    function ormpSender() public view virtual override returns (address) {
-        return _ORMP;
-    }
-
-    function ormpRecver() public view virtual override returns (address) {
+    function protocol() public view virtual override returns (address) {
         return _ORMP;
     }
 
     function _setAppConfig(address oracle, address relayer) internal virtual {
-        IORMP(_ORMP).setAppConfig(oracle, relayer);
+        IORMP(protocol()).setAppConfig(oracle, relayer);
     }
 }
diff --git a/src/user/UpgradeableApplication.sol b/src/user/UpgradeableApplication.sol
index 995ebce..1f0bc47 100644
--- a/src/user/UpgradeableApplication.sol
+++ b/src/user/UpgradeableApplication.sol
@@ -21,40 +21,24 @@ import "../interfaces/IORMP.sol";
 import "./AppBase.sol";
 
 abstract contract UpgradeableApplication is AppBase {
-    address private _sender;
-    address private _recver;
+    address private _ormp;
 
-    event SetSender(address ormp);
-    event SetRecver(address ormp);
+    event SetORMP(address ormp);
 
     constructor(address ormp) {
-        _sender = ormp;
-        _recver = ormp;
+        _ormp = ormp;
     }
 
-    function ormpSender() public view virtual override returns (address) {
-        return _sender;
+    function protocol() public view virtual override returns (address) {
+        return _ormp;
     }
 
-    function ormpRecver() public view virtual override returns (address) {
-        return _recver;
+    function _setORMP(address ormp) internal virtual {
+        _ormp = ormp;
+        emit SetORMP(ormp);
     }
 
-    function _setSender(address ormp) internal virtual {
-        _sender = ormp;
-        emit SetSender(ormp);
-    }
-
-    function _setRecver(address ormp) internal virtual {
-        _recver = ormp;
-        emit SetRecver(ormp);
-    }
-
-    function _setSenderConfig(address oracle, address relayer) internal virtual {
-        IORMP(ormpSender()).setAppConfig(oracle, relayer);
-    }
-
-    function _setRecverConfig(address oracle, address relayer) internal virtual {
-        IORMP(ormpRecver()).setAppConfig(oracle, relayer);
+    function _setAppConfig(address oracle, address relayer) internal virtual {
+        IORMP(protocol()).setAppConfig(oracle, relayer);
     }
 }
diff --git a/test/user/Application.t.sol b/test/user/Application.t.sol
index e83cf47..e390bec 100644
--- a/test/user/Application.t.sol
+++ b/test/user/Application.t.sol
@@ -57,6 +57,6 @@ contract UserApplication is Application {
         address xmsgSender = _xmsgSender();
         require(msgHash == bytes32(uint256(1)));
         require(fromChainid == 1);
-        require(xmsgSender == ormpRecver());
+        require(xmsgSender == protocol());
     }
 }