diff --git a/Lib/asyncio/base_subprocess.py b/Lib/asyncio/base_subprocess.py
index fb8c2ba72fe..28482b71896 100644
--- a/Lib/asyncio/base_subprocess.py
+++ b/Lib/asyncio/base_subprocess.py
@@ -87,6 +87,12 @@ class BaseSubprocessTransport(transports.SubprocessTransport):
     def _start(self, args, shell, stdin, stdout, stderr, bufsize, **kwargs):
         raise NotImplementedError
 
+    def set_protocol(self, protocol):
+        self._protocol = protocol
+
+    def get_protocol(self):
+        return self._protocol
+
     def is_closing(self):
         return self._closed
 
diff --git a/Lib/asyncio/proactor_events.py b/Lib/asyncio/proactor_events.py
index 4b6067aede7..68a523af958 100644
--- a/Lib/asyncio/proactor_events.py
+++ b/Lib/asyncio/proactor_events.py
@@ -66,6 +66,12 @@ class _ProactorBasePipeTransport(transports._FlowControlMixin,
     def _set_extra(self, sock):
         self._extra['pipe'] = sock
 
+    def set_protocol(self, protocol):
+        self._protocol = protocol
+
+    def get_protocol(self):
+        return self._protocol
+
     def is_closing(self):
         return self._closing
 
diff --git a/Lib/asyncio/selector_events.py b/Lib/asyncio/selector_events.py
index 34cce6b7a15..1850bdb5a11 100644
--- a/Lib/asyncio/selector_events.py
+++ b/Lib/asyncio/selector_events.py
@@ -560,6 +560,12 @@ class _SelectorTransport(transports._FlowControlMixin,
     def abort(self):
         self._force_close(None)
 
+    def set_protocol(self, protocol):
+        self._protocol = protocol
+
+    def get_protocol(self):
+        return self._protocol
+
     def is_closing(self):
         return self._closing
 
diff --git a/Lib/asyncio/sslproto.py b/Lib/asyncio/sslproto.py
index f0f642e4eab..92d3c4c9091 100644
--- a/Lib/asyncio/sslproto.py
+++ b/Lib/asyncio/sslproto.py
@@ -305,6 +305,12 @@ class _SSLProtocolTransport(transports._FlowControlMixin,
         """Get optional transport information."""
         return self._ssl_protocol._get_extra_info(name, default)
 
+    def set_protocol(self, protocol):
+        self._app_protocol = protocol
+
+    def get_protocol(self):
+        return self._app_protocol
+
     def is_closing(self):
         return self._closed
 
diff --git a/Lib/asyncio/transports.py b/Lib/asyncio/transports.py
index 9a6d9197d9a..0db08757156 100644
--- a/Lib/asyncio/transports.py
+++ b/Lib/asyncio/transports.py
@@ -33,6 +33,14 @@ class BaseTransport:
         """
         raise NotImplementedError
 
+    def set_protocol(self, protocol):
+        """Set a new protocol."""
+        raise NotImplementedError
+
+    def get_protocol(self):
+        """Return the current protocol."""
+        raise NotImplementedError
+
 
 class ReadTransport(BaseTransport):
     """Interface for read-only transports."""
diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py
index d183f60722c..4222054f265 100644
--- a/Lib/asyncio/unix_events.py
+++ b/Lib/asyncio/unix_events.py
@@ -374,6 +374,12 @@ class _UnixReadPipeTransport(transports.ReadTransport):
     def resume_reading(self):
         self._loop.add_reader(self._fileno, self._read_ready)
 
+    def set_protocol(self, protocol):
+        self._protocol = protocol
+
+    def get_protocol(self):
+        return self._protocol
+
     def is_closing(self):
         return self._closing
 
@@ -571,6 +577,12 @@ class _UnixWritePipeTransport(transports._FlowControlMixin,
             self._loop.remove_reader(self._fileno)
             self._loop.call_soon(self._call_connection_lost, None)
 
+    def set_protocol(self, protocol):
+        self._protocol = protocol
+
+    def get_protocol(self):
+        return self._protocol
+
     def is_closing(self):
         return self._closing
 
diff --git a/Lib/test/test_asyncio/test_sslproto.py b/Lib/test/test_asyncio/test_sslproto.py
index 8d5233565e4..7dfa6c2c63b 100644
--- a/Lib/test/test_asyncio/test_sslproto.py
+++ b/Lib/test/test_asyncio/test_sslproto.py
@@ -25,6 +25,7 @@ class SslProtoHandshakeTests(test_utils.TestCase):
         sslcontext = test_utils.dummy_ssl_context()
         app_proto = asyncio.Protocol()
         proto = sslproto.SSLProtocol(self.loop, app_proto, sslcontext, waiter)
+        self.assertIs(proto._app_transport.get_protocol(), app_proto)
         self.addCleanup(proto._app_transport.close)
         return proto