diff --git a/common/protocol/time.go b/common/protocol/time.go
new file mode 100644
index 000000000..bb3d61a07
--- /dev/null
+++ b/common/protocol/time.go
@@ -0,0 +1,11 @@
+package protocol
+
+import (
+	"github.com/v2ray/v2ray-core/common/serial"
+)
+
+type Timestamp int64
+
+func (this Timestamp) Bytes() []byte {
+	return serial.Int64Literal(this).Bytes()
+}