diff --git a/app/internal/proxymux/internal/mocks/mock_Conn.go b/app/internal/proxymux/internal/mocks/mock_Conn.go
index 0bcbe657d7..13e363e999 100644
--- a/app/internal/proxymux/internal/mocks/mock_Conn.go
+++ b/app/internal/proxymux/internal/mocks/mock_Conn.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.42.2. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
diff --git a/app/internal/proxymux/internal/mocks/mock_Listener.go b/app/internal/proxymux/internal/mocks/mock_Listener.go
index e4ca2f46cd..842b88f2d8 100644
--- a/app/internal/proxymux/internal/mocks/mock_Listener.go
+++ b/app/internal/proxymux/internal/mocks/mock_Listener.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.42.2. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
diff --git a/core/client/mock_udpIO.go b/core/client/mock_udpIO.go
index 6e0b1bab5b..a85e006d46 100644
--- a/core/client/mock_udpIO.go
+++ b/core/client/mock_udpIO.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package client
 
@@ -24,6 +24,10 @@ func (_m *mockUDPIO) EXPECT() *mockUDPIO_Expecter {
 func (_m *mockUDPIO) ReceiveMessage() (*protocol.UDPMessage, error) {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for ReceiveMessage")
+	}
+
 	var r0 *protocol.UDPMessage
 	var r1 error
 	if rf, ok := ret.Get(0).(func() (*protocol.UDPMessage, error)); ok {
@@ -77,6 +81,10 @@ func (_c *mockUDPIO_ReceiveMessage_Call) RunAndReturn(run func() (*protocol.UDPM
 func (_m *mockUDPIO) SendMessage(_a0 []byte, _a1 *protocol.UDPMessage) error {
 	ret := _m.Called(_a0, _a1)
 
+	if len(ret) == 0 {
+		panic("no return value specified for SendMessage")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func([]byte, *protocol.UDPMessage) error); ok {
 		r0 = rf(_a0, _a1)
diff --git a/core/internal/integration_tests/mocks/mock_Authenticator.go b/core/internal/integration_tests/mocks/mock_Authenticator.go
index 20329f71c0..b42c7374c7 100644
--- a/core/internal/integration_tests/mocks/mock_Authenticator.go
+++ b/core/internal/integration_tests/mocks/mock_Authenticator.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
@@ -25,6 +25,10 @@ func (_m *MockAuthenticator) EXPECT() *MockAuthenticator_Expecter {
 func (_m *MockAuthenticator) Authenticate(addr net.Addr, auth string, tx uint64) (bool, string) {
 	ret := _m.Called(addr, auth, tx)
 
+	if len(ret) == 0 {
+		panic("no return value specified for Authenticate")
+	}
+
 	var r0 bool
 	var r1 string
 	if rf, ok := ret.Get(0).(func(net.Addr, string, uint64) (bool, string)); ok {
diff --git a/core/internal/integration_tests/mocks/mock_Conn.go b/core/internal/integration_tests/mocks/mock_Conn.go
index 6840332b6a..13e363e999 100644
--- a/core/internal/integration_tests/mocks/mock_Conn.go
+++ b/core/internal/integration_tests/mocks/mock_Conn.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
@@ -27,6 +27,10 @@ func (_m *MockConn) EXPECT() *MockConn_Expecter {
 func (_m *MockConn) Close() error {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for Close")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func() error); ok {
 		r0 = rf()
@@ -68,6 +72,10 @@ func (_c *MockConn_Close_Call) RunAndReturn(run func() error) *MockConn_Close_Ca
 func (_m *MockConn) LocalAddr() net.Addr {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for LocalAddr")
+	}
+
 	var r0 net.Addr
 	if rf, ok := ret.Get(0).(func() net.Addr); ok {
 		r0 = rf()
@@ -111,6 +119,10 @@ func (_c *MockConn_LocalAddr_Call) RunAndReturn(run func() net.Addr) *MockConn_L
 func (_m *MockConn) Read(b []byte) (int, error) {
 	ret := _m.Called(b)
 
+	if len(ret) == 0 {
+		panic("no return value specified for Read")
+	}
+
 	var r0 int
 	var r1 error
 	if rf, ok := ret.Get(0).(func([]byte) (int, error)); ok {
@@ -163,6 +175,10 @@ func (_c *MockConn_Read_Call) RunAndReturn(run func([]byte) (int, error)) *MockC
 func (_m *MockConn) RemoteAddr() net.Addr {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for RemoteAddr")
+	}
+
 	var r0 net.Addr
 	if rf, ok := ret.Get(0).(func() net.Addr); ok {
 		r0 = rf()
@@ -206,6 +222,10 @@ func (_c *MockConn_RemoteAddr_Call) RunAndReturn(run func() net.Addr) *MockConn_
 func (_m *MockConn) SetDeadline(t time.Time) error {
 	ret := _m.Called(t)
 
+	if len(ret) == 0 {
+		panic("no return value specified for SetDeadline")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func(time.Time) error); ok {
 		r0 = rf(t)
@@ -248,6 +268,10 @@ func (_c *MockConn_SetDeadline_Call) RunAndReturn(run func(time.Time) error) *Mo
 func (_m *MockConn) SetReadDeadline(t time.Time) error {
 	ret := _m.Called(t)
 
+	if len(ret) == 0 {
+		panic("no return value specified for SetReadDeadline")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func(time.Time) error); ok {
 		r0 = rf(t)
@@ -290,6 +314,10 @@ func (_c *MockConn_SetReadDeadline_Call) RunAndReturn(run func(time.Time) error)
 func (_m *MockConn) SetWriteDeadline(t time.Time) error {
 	ret := _m.Called(t)
 
+	if len(ret) == 0 {
+		panic("no return value specified for SetWriteDeadline")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func(time.Time) error); ok {
 		r0 = rf(t)
@@ -332,6 +360,10 @@ func (_c *MockConn_SetWriteDeadline_Call) RunAndReturn(run func(time.Time) error
 func (_m *MockConn) Write(b []byte) (int, error) {
 	ret := _m.Called(b)
 
+	if len(ret) == 0 {
+		panic("no return value specified for Write")
+	}
+
 	var r0 int
 	var r1 error
 	if rf, ok := ret.Get(0).(func([]byte) (int, error)); ok {
diff --git a/core/internal/integration_tests/mocks/mock_EventLogger.go b/core/internal/integration_tests/mocks/mock_EventLogger.go
index cf63773a95..c9f69207f8 100644
--- a/core/internal/integration_tests/mocks/mock_EventLogger.go
+++ b/core/internal/integration_tests/mocks/mock_EventLogger.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
diff --git a/core/internal/integration_tests/mocks/mock_Outbound.go b/core/internal/integration_tests/mocks/mock_Outbound.go
index 32a747b63e..1a2d0c6325 100644
--- a/core/internal/integration_tests/mocks/mock_Outbound.go
+++ b/core/internal/integration_tests/mocks/mock_Outbound.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
@@ -27,6 +27,10 @@ func (_m *MockOutbound) EXPECT() *MockOutbound_Expecter {
 func (_m *MockOutbound) TCP(reqAddr string) (net.Conn, error) {
 	ret := _m.Called(reqAddr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for TCP")
+	}
+
 	var r0 net.Conn
 	var r1 error
 	if rf, ok := ret.Get(0).(func(string) (net.Conn, error)); ok {
@@ -81,6 +85,10 @@ func (_c *MockOutbound_TCP_Call) RunAndReturn(run func(string) (net.Conn, error)
 func (_m *MockOutbound) UDP(reqAddr string) (server.UDPConn, error) {
 	ret := _m.Called(reqAddr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for UDP")
+	}
+
 	var r0 server.UDPConn
 	var r1 error
 	if rf, ok := ret.Get(0).(func(string) (server.UDPConn, error)); ok {
diff --git a/core/internal/integration_tests/mocks/mock_TrafficLogger.go b/core/internal/integration_tests/mocks/mock_TrafficLogger.go
index 0188ab3356..9de44b976e 100644
--- a/core/internal/integration_tests/mocks/mock_TrafficLogger.go
+++ b/core/internal/integration_tests/mocks/mock_TrafficLogger.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
@@ -17,10 +17,48 @@ func (_m *MockTrafficLogger) EXPECT() *MockTrafficLogger_Expecter {
 	return &MockTrafficLogger_Expecter{mock: &_m.Mock}
 }
 
-// Log provides a mock function with given fields: id, tx, rx
-func (_m *MockTrafficLogger) Log(id string, tx uint64, rx uint64) bool {
+// LogOnlineState provides a mock function with given fields: id, online
+func (_m *MockTrafficLogger) LogOnlineState(id string, online bool) {
+	_m.Called(id, online)
+}
+
+// MockTrafficLogger_LogOnlineState_Call is a *mock.Call that shadows Run/Return methods with type explicit version for method 'LogOnlineState'
+type MockTrafficLogger_LogOnlineState_Call struct {
+	*mock.Call
+}
+
+// LogOnlineState is a helper method to define mock.On call
+//   - id string
+//   - online bool
+func (_e *MockTrafficLogger_Expecter) LogOnlineState(id interface{}, online interface{}) *MockTrafficLogger_LogOnlineState_Call {
+	return &MockTrafficLogger_LogOnlineState_Call{Call: _e.mock.On("LogOnlineState", id, online)}
+}
+
+func (_c *MockTrafficLogger_LogOnlineState_Call) Run(run func(id string, online bool)) *MockTrafficLogger_LogOnlineState_Call {
+	_c.Call.Run(func(args mock.Arguments) {
+		run(args[0].(string), args[1].(bool))
+	})
+	return _c
+}
+
+func (_c *MockTrafficLogger_LogOnlineState_Call) Return() *MockTrafficLogger_LogOnlineState_Call {
+	_c.Call.Return()
+	return _c
+}
+
+func (_c *MockTrafficLogger_LogOnlineState_Call) RunAndReturn(run func(string, bool)) *MockTrafficLogger_LogOnlineState_Call {
+	_c.Call.Return(run)
+	return _c
+}
+
+// LogTraffic provides a mock function with given fields: id, tx, rx
+func (_m *MockTrafficLogger) LogTraffic(id string, tx uint64, rx uint64) bool {
 	ret := _m.Called(id, tx, rx)
 
+	if len(ret) == 0 {
+		panic("no return value specified for LogTraffic")
+	}
+
 	var r0 bool
 	if rf, ok := ret.Get(0).(func(string, uint64, uint64) bool); ok {
 		r0 = rf(id, tx, rx)
@@ -31,32 +69,32 @@ func (_m *MockTrafficLogger) Log(id string, tx uint64, rx uint64) bool {
 	return r0
 }
 
-// MockTrafficLogger_Log_Call is a *mock.Call that shadows Run/Return methods with type explicit version for method 'Log'
-type MockTrafficLogger_Log_Call struct {
+// MockTrafficLogger_LogTraffic_Call is a *mock.Call that shadows Run/Return methods with type explicit version for method 'LogTraffic'
+type MockTrafficLogger_LogTraffic_Call struct {
 	*mock.Call
 }
 
-// Log is a helper method to define mock.On call
+// LogTraffic is a helper method to define mock.On call
 //   - id string
 //   - tx uint64
 //   - rx uint64
-func (_e *MockTrafficLogger_Expecter) Log(id interface{}, tx interface{}, rx interface{}) *MockTrafficLogger_Log_Call {
-	return &MockTrafficLogger_Log_Call{Call: _e.mock.On("Log", id, tx, rx)}
+func (_e *MockTrafficLogger_Expecter) LogTraffic(id interface{}, tx interface{}, rx interface{}) *MockTrafficLogger_LogTraffic_Call {
+	return &MockTrafficLogger_LogTraffic_Call{Call: _e.mock.On("LogTraffic", id, tx, rx)}
 }
 
-func (_c *MockTrafficLogger_Log_Call) Run(run func(id string, tx uint64, rx uint64)) *MockTrafficLogger_Log_Call {
+func (_c *MockTrafficLogger_LogTraffic_Call) Run(run func(id string, tx uint64, rx uint64)) *MockTrafficLogger_LogTraffic_Call {
 	_c.Call.Run(func(args mock.Arguments) {
 		run(args[0].(string), args[1].(uint64), args[2].(uint64))
 	})
 	return _c
 }
 
-func (_c *MockTrafficLogger_Log_Call) Return(ok bool) *MockTrafficLogger_Log_Call {
+func (_c *MockTrafficLogger_LogTraffic_Call) Return(ok bool) *MockTrafficLogger_LogTraffic_Call {
 	_c.Call.Return(ok)
 	return _c
 }
 
-func (_c *MockTrafficLogger_Log_Call) RunAndReturn(run func(string, uint64, uint64) bool) *MockTrafficLogger_Log_Call {
+func (_c *MockTrafficLogger_LogTraffic_Call) RunAndReturn(run func(string, uint64, uint64) bool) *MockTrafficLogger_LogTraffic_Call {
 	_c.Call.Return(run)
 	return _c
 }
diff --git a/core/internal/integration_tests/mocks/mock_UDPConn.go b/core/internal/integration_tests/mocks/mock_UDPConn.go
index 808c18b5dd..b88387086d 100644
--- a/core/internal/integration_tests/mocks/mock_UDPConn.go
+++ b/core/internal/integration_tests/mocks/mock_UDPConn.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package mocks
 
@@ -21,6 +21,10 @@ func (_m *MockUDPConn) EXPECT() *MockUDPConn_Expecter {
 func (_m *MockUDPConn) Close() error {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for Close")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func() error); ok {
 		r0 = rf()
@@ -62,6 +66,10 @@ func (_c *MockUDPConn_Close_Call) RunAndReturn(run func() error) *MockUDPConn_Cl
 func (_m *MockUDPConn) ReadFrom(b []byte) (int, string, error) {
 	ret := _m.Called(b)
 
+	if len(ret) == 0 {
+		panic("no return value specified for ReadFrom")
+	}
+
 	var r0 int
 	var r1 string
 	var r2 error
@@ -121,6 +129,10 @@ func (_c *MockUDPConn_ReadFrom_Call) RunAndReturn(run func([]byte) (int, string,
 func (_m *MockUDPConn) WriteTo(b []byte, addr string) (int, error) {
 	ret := _m.Called(b, addr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for WriteTo")
+	}
+
 	var r0 int
 	var r1 error
 	if rf, ok := ret.Get(0).(func([]byte, string) (int, error)); ok {
diff --git a/core/internal/integration_tests/trafficlogger_test.go b/core/internal/integration_tests/trafficlogger_test.go
index abbea8cdd3..690a348d72 100644
--- a/core/internal/integration_tests/trafficlogger_test.go
+++ b/core/internal/integration_tests/trafficlogger_test.go
@@ -36,6 +36,7 @@ func TestClientServerTrafficLoggerTCP(t *testing.T) {
 	go s.Serve()
 
 	// Create client
+	trafficLogger.EXPECT().LogOnlineState("nobody", true).Return().Once()
 	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
@@ -66,7 +67,7 @@ func TestClientServerTrafficLoggerTCP(t *testing.T) {
 	assert.NoError(t, err)
 
 	// Client reads from server
-	trafficLogger.EXPECT().Log("nobody", uint64(0), uint64(11)).Return(true).Once()
+	trafficLogger.EXPECT().LogTraffic("nobody", uint64(0), uint64(11)).Return(true).Once()
 	sobConnCh <- []byte("knock knock")
 	buf := make([]byte, 100)
 	n, err := conn.Read(buf)
@@ -75,7 +76,7 @@ func TestClientServerTrafficLoggerTCP(t *testing.T) {
 	assert.Equal(t, "knock knock", string(buf[:n]))
 
 	// Client writes to server
-	trafficLogger.EXPECT().Log("nobody", uint64(12), uint64(0)).Return(true).Once()
+	trafficLogger.EXPECT().LogTraffic("nobody", uint64(12), uint64(0)).Return(true).Once()
 	sobConn.EXPECT().Write([]byte("who is there")).Return(12, nil).Once()
 	n, err = conn.Write([]byte("who is there"))
 	assert.NoError(t, err)
@@ -83,7 +84,8 @@ func TestClientServerTrafficLoggerTCP(t *testing.T) {
 	time.Sleep(1 * time.Second) // Need some time for the server to receive the data
 
 	// Client reads from server again but blocked
-	trafficLogger.EXPECT().Log("nobody", uint64(0), uint64(4)).Return(false).Once()
+	trafficLogger.EXPECT().LogTraffic("nobody", uint64(0), uint64(4)).Return(false).Once()
+	trafficLogger.EXPECT().LogOnlineState("nobody", false).Return().Once()
 	sobConnCh <- []byte("nope")
 	n, err = conn.Read(buf)
 	assert.Zero(t, n)
@@ -116,6 +118,7 @@ func TestClientServerTrafficLoggerUDP(t *testing.T) {
 	go s.Serve()
 
 	// Create client
+	trafficLogger.EXPECT().LogOnlineState("nobody", true).Return().Once()
 	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
@@ -146,14 +149,14 @@ func TestClientServerTrafficLoggerUDP(t *testing.T) {
 	assert.NoError(t, err)
 
 	// Client writes to server
-	trafficLogger.EXPECT().Log("nobody", uint64(9), uint64(0)).Return(true).Once()
+	trafficLogger.EXPECT().LogTraffic("nobody", uint64(9), uint64(0)).Return(true).Once()
 	sobConn.EXPECT().WriteTo([]byte("small sad"), addr).Return(9, nil).Once()
 	err = conn.Send([]byte("small sad"), addr)
 	assert.NoError(t, err)
 	time.Sleep(1 * time.Second) // Need some time for the server to receive the data
 
 	// Client reads from server
-	trafficLogger.EXPECT().Log("nobody", uint64(0), uint64(7)).Return(true).Once()
+	trafficLogger.EXPECT().LogTraffic("nobody", uint64(0), uint64(7)).Return(true).Once()
 	sobConnCh <- []byte("big mad")
 	bs, rAddr, err := conn.Receive()
 	assert.NoError(t, err)
@@ -161,7 +164,8 @@ func TestClientServerTrafficLoggerUDP(t *testing.T) {
 	assert.Equal(t, "big mad", string(bs))
 
 	// Client reads from server again but blocked
-	trafficLogger.EXPECT().Log("nobody", uint64(0), uint64(4)).Return(false).Once()
+	trafficLogger.EXPECT().LogTraffic("nobody", uint64(0), uint64(4)).Return(false).Once()
+	trafficLogger.EXPECT().LogOnlineState("nobody", false).Return().Once()
 	sobConnCh <- []byte("nope")
 	bs, rAddr, err = conn.Receive()
 	assert.Equal(t, err, io.EOF)
diff --git a/core/server/config.go b/core/server/config.go
index f647f0d960..8d5f5dbc05 100644
--- a/core/server/config.go
+++ b/core/server/config.go
@@ -195,5 +195,6 @@ type EventLogger interface {
 // bandwidth limits or post-connection authentication, for example.
 // The implementation of this interface must be thread-safe.
 type TrafficLogger interface {
-	Log(id string, tx, rx uint64) (ok bool)
+	LogTraffic(id string, tx, rx uint64) (ok bool)
+	LogOnlineState(id string, online bool)
 }
diff --git a/core/server/copy.go b/core/server/copy.go
index 25831e5d34..d55dcefe3f 100644
--- a/core/server/copy.go
+++ b/core/server/copy.go
@@ -35,12 +35,12 @@ func copyTwoWayWithLogger(id string, serverRw, remoteRw io.ReadWriter, l Traffic
 	errChan := make(chan error, 2)
 	go func() {
 		errChan <- copyBufferLog(serverRw, remoteRw, func(n uint64) bool {
-			return l.Log(id, 0, n)
+			return l.LogTraffic(id, 0, n)
 		})
 	}()
 	go func() {
 		errChan <- copyBufferLog(remoteRw, serverRw, func(n uint64) bool {
-			return l.Log(id, n, 0)
+			return l.LogTraffic(id, n, 0)
 		})
 	}()
 	// Block until one of the two goroutines returns
diff --git a/core/server/mock_UDPConn.go b/core/server/mock_UDPConn.go
index 34a34ee900..7299975353 100644
--- a/core/server/mock_UDPConn.go
+++ b/core/server/mock_UDPConn.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package server
 
@@ -21,6 +21,10 @@ func (_m *mockUDPConn) EXPECT() *mockUDPConn_Expecter {
 func (_m *mockUDPConn) Close() error {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for Close")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func() error); ok {
 		r0 = rf()
@@ -62,6 +66,10 @@ func (_c *mockUDPConn_Close_Call) RunAndReturn(run func() error) *mockUDPConn_Cl
 func (_m *mockUDPConn) ReadFrom(b []byte) (int, string, error) {
 	ret := _m.Called(b)
 
+	if len(ret) == 0 {
+		panic("no return value specified for ReadFrom")
+	}
+
 	var r0 int
 	var r1 string
 	var r2 error
@@ -121,6 +129,10 @@ func (_c *mockUDPConn_ReadFrom_Call) RunAndReturn(run func([]byte) (int, string,
 func (_m *mockUDPConn) WriteTo(b []byte, addr string) (int, error) {
 	ret := _m.Called(b, addr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for WriteTo")
+	}
+
 	var r0 int
 	var r1 error
 	if rf, ok := ret.Get(0).(func([]byte, string) (int, error)); ok {
diff --git a/core/server/mock_udpEventLogger.go b/core/server/mock_udpEventLogger.go
index 08f3ff8d86..5a54b0ba6a 100644
--- a/core/server/mock_udpEventLogger.go
+++ b/core/server/mock_udpEventLogger.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package server
 
diff --git a/core/server/mock_udpIO.go b/core/server/mock_udpIO.go
index ddd44b3abe..6df862b5f6 100644
--- a/core/server/mock_udpIO.go
+++ b/core/server/mock_udpIO.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package server
 
@@ -24,6 +24,10 @@ func (_m *mockUDPIO) EXPECT() *mockUDPIO_Expecter {
 func (_m *mockUDPIO) ReceiveMessage() (*protocol.UDPMessage, error) {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for ReceiveMessage")
+	}
+
 	var r0 *protocol.UDPMessage
 	var r1 error
 	if rf, ok := ret.Get(0).(func() (*protocol.UDPMessage, error)); ok {
@@ -77,6 +81,10 @@ func (_c *mockUDPIO_ReceiveMessage_Call) RunAndReturn(run func() (*protocol.UDPM
 func (_m *mockUDPIO) SendMessage(_a0 []byte, _a1 *protocol.UDPMessage) error {
 	ret := _m.Called(_a0, _a1)
 
+	if len(ret) == 0 {
+		panic("no return value specified for SendMessage")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func([]byte, *protocol.UDPMessage) error); ok {
 		r0 = rf(_a0, _a1)
@@ -120,6 +128,10 @@ func (_c *mockUDPIO_SendMessage_Call) RunAndReturn(run func([]byte, *protocol.UD
 func (_m *mockUDPIO) UDP(reqAddr string) (UDPConn, error) {
 	ret := _m.Called(reqAddr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for UDP")
+	}
+
 	var r0 UDPConn
 	var r1 error
 	if rf, ok := ret.Get(0).(func(string) (UDPConn, error)); ok {
diff --git a/core/server/server.go b/core/server/server.go
index 78ab53166a..d38097dc70 100644
--- a/core/server/server.go
+++ b/core/server/server.go
@@ -82,8 +82,13 @@ func (s *serverImpl) handleClient(conn quic.Connection) {
 	}
 	err := h3s.ServeQUICConn(conn)
 	// If the client is authenticated, we need to log the disconnect event
-	if handler.authenticated && s.config.EventLogger != nil {
-		s.config.EventLogger.Disconnect(conn.RemoteAddr(), handler.authID, err)
+	if handler.authenticated {
+		if tl := s.config.TrafficLogger; tl != nil {
+			tl.LogOnlineState(handler.authID, false)
+		}
+		if el := s.config.EventLogger; el != nil {
+			el.Disconnect(conn.RemoteAddr(), handler.authID, err)
+		}
 	}
 	_ = conn.CloseWithError(closeErrCodeOK, "")
 }
@@ -153,8 +158,11 @@ func (h *h3sHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			})
 			w.WriteHeader(protocol.StatusAuthOK)
 			// Call event logger
-			if h.config.EventLogger != nil {
-				h.config.EventLogger.Connect(h.conn.RemoteAddr(), id, actualTx)
+			if tl := h.config.TrafficLogger; tl != nil {
+				tl.LogOnlineState(id, true)
+			}
+			if el := h.config.EventLogger; el != nil {
+				el.Connect(h.conn.RemoteAddr(), id, actualTx)
 			}
 			// Initialize UDP session manager (if UDP is enabled)
 			// We use sync.Once to make sure that only one goroutine is started,
@@ -268,7 +276,7 @@ func (io *udpIOImpl) ReceiveMessage() (*protocol.UDPMessage, error) {
 			continue
 		}
 		if io.TrafficLogger != nil {
-			ok := io.TrafficLogger.Log(io.AuthID, uint64(len(udpMsg.Data)), 0)
+			ok := io.TrafficLogger.LogTraffic(io.AuthID, uint64(len(udpMsg.Data)), 0)
 			if !ok {
 				// TrafficLogger requested to disconnect the client
 				_ = io.Conn.CloseWithError(closeErrCodeTrafficLimitReached, "")
@@ -281,7 +289,7 @@ func (io *udpIOImpl) ReceiveMessage() (*protocol.UDPMessage, error) {
 
 func (io *udpIOImpl) SendMessage(buf []byte, msg *protocol.UDPMessage) error {
 	if io.TrafficLogger != nil {
-		ok := io.TrafficLogger.Log(io.AuthID, 0, uint64(len(msg.Data)))
+		ok := io.TrafficLogger.LogTraffic(io.AuthID, 0, uint64(len(msg.Data)))
 		if !ok {
 			// TrafficLogger requested to disconnect the client
 			_ = io.Conn.CloseWithError(closeErrCodeTrafficLimitReached, "")
diff --git a/extras/outbounds/mock_PluggableOutbound.go b/extras/outbounds/mock_PluggableOutbound.go
index c8620f2530..79b38e4295 100644
--- a/extras/outbounds/mock_PluggableOutbound.go
+++ b/extras/outbounds/mock_PluggableOutbound.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package outbounds
 
@@ -25,6 +25,10 @@ func (_m *mockPluggableOutbound) EXPECT() *mockPluggableOutbound_Expecter {
 func (_m *mockPluggableOutbound) TCP(reqAddr *AddrEx) (net.Conn, error) {
 	ret := _m.Called(reqAddr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for TCP")
+	}
+
 	var r0 net.Conn
 	var r1 error
 	if rf, ok := ret.Get(0).(func(*AddrEx) (net.Conn, error)); ok {
@@ -79,6 +83,10 @@ func (_c *mockPluggableOutbound_TCP_Call) RunAndReturn(run func(*AddrEx) (net.Co
 func (_m *mockPluggableOutbound) UDP(reqAddr *AddrEx) (UDPConn, error) {
 	ret := _m.Called(reqAddr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for UDP")
+	}
+
 	var r0 UDPConn
 	var r1 error
 	if rf, ok := ret.Get(0).(func(*AddrEx) (UDPConn, error)); ok {
diff --git a/extras/outbounds/mock_UDPConn.go b/extras/outbounds/mock_UDPConn.go
index e71e1da065..d450322a4f 100644
--- a/extras/outbounds/mock_UDPConn.go
+++ b/extras/outbounds/mock_UDPConn.go
@@ -1,4 +1,4 @@
-// Code generated by mockery v2.32.0. DO NOT EDIT.
+// Code generated by mockery v2.43.0. DO NOT EDIT.
 
 package outbounds
 
@@ -21,6 +21,10 @@ func (_m *mockUDPConn) EXPECT() *mockUDPConn_Expecter {
 func (_m *mockUDPConn) Close() error {
 	ret := _m.Called()
 
+	if len(ret) == 0 {
+		panic("no return value specified for Close")
+	}
+
 	var r0 error
 	if rf, ok := ret.Get(0).(func() error); ok {
 		r0 = rf()
@@ -62,6 +66,10 @@ func (_c *mockUDPConn_Close_Call) RunAndReturn(run func() error) *mockUDPConn_Cl
 func (_m *mockUDPConn) ReadFrom(b []byte) (int, *AddrEx, error) {
 	ret := _m.Called(b)
 
+	if len(ret) == 0 {
+		panic("no return value specified for ReadFrom")
+	}
+
 	var r0 int
 	var r1 *AddrEx
 	var r2 error
@@ -123,6 +131,10 @@ func (_c *mockUDPConn_ReadFrom_Call) RunAndReturn(run func([]byte) (int, *AddrEx
 func (_m *mockUDPConn) WriteTo(b []byte, addr *AddrEx) (int, error) {
 	ret := _m.Called(b, addr)
 
+	if len(ret) == 0 {
+		panic("no return value specified for WriteTo")
+	}
+
 	var r0 int
 	var r1 error
 	if rf, ok := ret.Get(0).(func([]byte, *AddrEx) (int, error)); ok {
diff --git a/extras/trafficlogger/http.go b/extras/trafficlogger/http.go
index 428dd94cbd..d0ec0a4cee 100644
--- a/extras/trafficlogger/http.go
+++ b/extras/trafficlogger/http.go
@@ -22,17 +22,19 @@ type TrafficStatsServer interface {
 
 func NewTrafficStatsServer(secret string) TrafficStatsServer {
 	return &trafficStatsServerImpl{
-		StatsMap: make(map[string]*trafficStatsEntry),
-		KickMap:  make(map[string]struct{}),
-		Secret:   secret,
+		StatsMap:  make(map[string]*trafficStatsEntry),
+		KickMap:   make(map[string]struct{}),
+		OnlineMap: make(map[string]int),
+		Secret:    secret,
 	}
 }
 
 type trafficStatsServerImpl struct {
-	Mutex    sync.RWMutex
-	StatsMap map[string]*trafficStatsEntry
-	KickMap  map[string]struct{}
-	Secret   string
+	Mutex     sync.RWMutex
+	StatsMap  map[string]*trafficStatsEntry
+	OnlineMap map[string]int
+	KickMap   map[string]struct{}
+	Secret    string
 }
 
 type trafficStatsEntry struct {
@@ -40,7 +42,7 @@ type trafficStatsEntry struct {
 	Rx uint64 `json:"rx"`
 }
 
-func (s *trafficStatsServerImpl) Log(id string, tx, rx uint64) (ok bool) {
+func (s *trafficStatsServerImpl) LogTraffic(id string, tx, rx uint64) (ok bool) {
 	s.Mutex.Lock()
 	defer s.Mutex.Unlock()
 
@@ -61,6 +63,21 @@ func (s *trafficStatsServerImpl) Log(id string, tx, rx uint64) (ok bool) {
 	return true
 }
 
+// LogOnlineStateChanged updates the online state to the online map.
+func (s *trafficStatsServerImpl) LogOnlineState(id string, online bool) {
+	s.Mutex.Lock()
+	defer s.Mutex.Unlock()
+
+	if online {
+		s.OnlineMap[id]++
+	} else {
+		s.OnlineMap[id]--
+		if s.OnlineMap[id] <= 0 {
+			delete(s.OnlineMap, id)
+		}
+	}
+}
+
 func (s *trafficStatsServerImpl) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if s.Secret != "" && r.Header.Get("Authorization") != s.Secret {
 		http.Error(w, "unauthorized", http.StatusUnauthorized)
@@ -78,6 +95,10 @@ func (s *trafficStatsServerImpl) ServeHTTP(w http.ResponseWriter, r *http.Reques
 		s.kick(w, r)
 		return
 	}
+	if r.Method == http.MethodGet && r.URL.Path == "/online" {
+		s.getOnline(w, r)
+		return
+	}
 	http.NotFound(w, r)
 }
 
@@ -103,6 +124,19 @@ func (s *trafficStatsServerImpl) getTraffic(w http.ResponseWriter, r *http.Reque
 	_, _ = w.Write(jb)
 }
 
+func (s *trafficStatsServerImpl) getOnline(w http.ResponseWriter, r *http.Request) {
+	s.Mutex.RLock()
+	defer s.Mutex.RUnlock()
+
+	jb, err := json.Marshal(s.OnlineMap)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	_, _ = w.Write(jb)
+}
+
 func (s *trafficStatsServerImpl) kick(w http.ResponseWriter, r *http.Request) {
 	var ids []string
 	err := json.NewDecoder(r.Body).Decode(&ids)