diff --git a/core/auth.proto b/core/auth.proto
index cb069a7..0653b08 100644
--- a/core/auth.proto
+++ b/core/auth.proto
@@ -13,4 +13,4 @@ message AuthenticateRequest {
 
 message AuthenticateResponse {
   string token = 1;
-}
\ No newline at end of file
+}
diff --git a/core/vpn.proto b/core/vpn.proto
deleted file mode 100644
index 6db43cd..0000000
--- a/core/vpn.proto
+++ /dev/null
@@ -1,88 +0,0 @@
-syntax = "proto3";
-
-package vpn;
-
-// This service is used by clients to create a VPN mesh.
-service VpnService {
-  // Store DeviceInfo data on the server so that it can be distributed to other
-  // clients and used to broker connections. Perform update if the device with
-  // given id already exists.
-  rpc RegisterDevice(RegisterDeviceRequest) returns (RegisterDeviceResponse);
-
-  // Get static information about all devices in the system. As the information
-  // changes, new versions will be streamed back.
-  rpc GetDevicesInfo(GetDevicesInfoRequest)
-      returns (stream DevicesInfo);
-
-  // Broker creating a new connection.
-  // Devices learn about each other via GetDevicesInfo. When they do, they
-  // should try to connect to each other via this call. Both should send each
-  // other their ICE info. The server, once it gets a response will forward it
-  // to the other client and close the stream. The only reason why the response
-  // is a stream rather than a single RPC is to reflect this RPC's potential
-  // long duration (e.g. when one of the devices is offline). Each client will
-  // have at most one `BrokerConnection` per one peer pending.
-  rpc BrokerConnection(BrokerConnectionRequest)
-      returns (stream BrokerConnectionResponse);
-}
-
-// The information about a device.
-message DeviceInfo {
-  // User-presentable device name.
-  string name = 1;
-  // Unique machine identifier. This is stored on the client device.
-  int64 id = 2;
-  // The IP address assigned to the device on the WG interface.
-  string ip_address = 3;
-  // Wireguard public key of the device.
-  string wg_public_key = 4;
-}
-
-message GetDevicesInfoRequest {
-  int64 device_id = 1;
-}
-
-// A list of DeviceInfos.
-message DevicesInfo {
-  repeated DeviceInfo devices = 1;
-}
-
-message BrokerConnectionRequest {
-  int64 my_device_id = 1;
-  int64 peer_device_id = 2;
-  ICEAgentInfo my_ice_agent_info = 3;
-}
-
-message BrokerConnectionResponse {
-  int64 peer_device_id = 2;
-  ICEAgentInfo peer_ice_agent_info = 3;
-}
-
-message RegisterDeviceRequest {
-  DeviceInfo device = 1;
-}
-
-message RegisterDeviceResponse {
-
-}
-
-// This structure contains the information necessary to construct a remote ICE
-// agent, except for username fragment
-message ICEAgentInfo {
-  // ICE user & password as described in section 5.3 of RFC 8445. This is
-  // generated randomly by the clients on every restart.
-  string user = 1;
-  string password = 2;
-  
-  repeated ICECandidate candidates = 3;
-}
-
-// This structure describes a single ICE candidate according to section 5.3 of
-// RFC 8445. Refer to the RFC for meaning of the fields.
-message ICECandidate {
-  string foundation = 1;
-  int32 priority = 2;
-  string ip_address = 3;
-  int32 port = 4;
-  int32 type = 5;
-}
diff --git a/wireguard/gateway.proto b/wireguard/gateway.proto
index 4b6affb..7245fdb 100644
--- a/wireguard/gateway.proto
+++ b/wireguard/gateway.proto
@@ -4,9 +4,13 @@ package gateway;
 import "google/protobuf/empty.proto";
 
 message ConfigurationRequest {
-  optional string name = 1;
+  string auth_token = 1;
+  string hostname = 2;
 }
 
+/*
+ * Networking and VPN configuration send from core to gateway.
+ */
 message Configuration {
   string name = 1;
   string prvkey = 2;
@@ -47,18 +51,35 @@ message PeerStats {
 }
 
 /*
- * Allow empty messages to keep the connection alive.
+ * CoreResponse represents messages send from core to gateway
+ * in response to CoreRequest.
  */
-message StatsUpdate {
+message CoreResponse {
   uint64 id = 1;
   oneof payload {
+    // Allow empty messages to keep the connection alive.
     google.protobuf.Empty empty = 2;
-    PeerStats peer_stats = 3;
+    Configuration config = 3;
+    Update update = 4;
   }
 }
 
-service GatewayService {
-  rpc Config (ConfigurationRequest) returns (Configuration);
-  rpc Updates (google.protobuf.Empty) returns (stream Update);
-  rpc Stats (stream StatsUpdate) returns (google.protobuf.Empty);
+/*
+ * CoreRequest represents messages send from gateway to core.
+ */
+message CoreRequest {
+  uint64 id = 1;
+  oneof payload {
+    PeerStats peer_stats = 2;
+    ConfigurationRequest config_request = 3;
+  }
+}
+
+/*
+ * Bi-directional communication between core and gateway.
+ * For security reasons, the connection has to be initiated by core,
+ * so requests and responses are actually send in reverse.
+ */
+service Gateway {
+  rpc Bidi (stream CoreResponse) returns (stream CoreRequest);
 }