diff --git a/config/config.py b/config/config.py
new file mode 100644
index 0000000..fb63607
--- /dev/null
+++ b/config/config.py
@@ -0,0 +1,2 @@
+port = 8426
+priKeySavePath = "./priKey.txt"
\ No newline at end of file
diff --git a/entity/Letter.py b/entity/Letter.py
index ced3545..e5b4113 100644
--- a/entity/Letter.py
+++ b/entity/Letter.py
@@ -1,7 +1,7 @@
 class Letter:
-    sign = ""
+    sign = "计算得到"
     encryptType = "SM4-GCM"
-    encryptKey = ""
+    encryptKey = "计算获得"
     recvPubKey = ""
     senderPubKey = ""
 
diff --git a/recv/recv.py b/recv/recv.py
index e69de29..d0c8c31 100644
--- a/recv/recv.py
+++ b/recv/recv.py
@@ -0,0 +1,12 @@
+from entity.Letter import Letter
+
+def getLetter():
+    # 阻塞自身 从指定端口获取信件
+    #
+    # 解析信件
+    letter = None
+    handleLetter(letter)
+    pass
+
+def handleLetter(letter:Letter):
+    pass
\ No newline at end of file
diff --git a/sender/sender.py b/sender/sender.py
index e69de29..30aad6c 100644
--- a/sender/sender.py
+++ b/sender/sender.py
@@ -0,0 +1,11 @@
+from entity.Letter import Letter
+
+def main():
+    # 用户输入各种数据填充letter字段
+    # 获取用户的公私钥对进行签名
+    # 使用对方的公钥进行加密
+    # 发送信件
+    pass
+def sendLetter(letter: Letter, target="192.168.195.162:8426"):
+    # 向目标ip和端口发送指定的信件
+    pass
diff --git a/tool/PriKeyHelper.py b/tool/PriKeyHelper.py
new file mode 100644
index 0000000..23feb16
--- /dev/null
+++ b/tool/PriKeyHelper.py
@@ -0,0 +1,4 @@
+def getUserKey() -> (str, str):
+    # 获取用户的公私钥对，若不存在，则生成之
+    # 返回 私钥，公钥 格式
+    pass