diff --git a/Cargo.lock b/Cargo.lock
index 1099912..a1ee8b9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -487,6 +487,7 @@ name = "orb-relay-messages"
 version = "0.0.0"
 dependencies = [
  "prost",
+ "prost-types",
  "tonic",
  "tonic-build",
 ]
diff --git a/proto/dataxchg/dataxchg.proto b/proto/dataxchg/dataxchg.proto
new file mode 100644
index 0000000..38a600d
--- /dev/null
+++ b/proto/dataxchg/dataxchg.proto
@@ -0,0 +1,59 @@
+syntax = "proto3";
+
+package dataxchg;
+
+import "google/protobuf/timestamp.proto";
+
+// Indirect references to specific data sources
+enum DataSource {
+  DATA_SOURCE_UNDEFINED = 0;
+  LATEST_SCAN_IMAGE = 1;
+  ORB_CONFIG = 2;
+}
+
+// binary format of source data
+enum DataFormat {
+  DATA_FORMAT_UNDEFINED = 0;
+  JSON = 1;
+  CSV = 2;
+  PNG = 3;
+  JPEG = 4;
+  TEXT = 5;
+  RAW = 6;
+}
+
+// Reference to data source to be exchanged
+message DataReference {
+  oneof source {
+    DataSource data_source = 1;
+    string file_path = 2;
+  }
+}
+
+// Metadata for data source
+message DataSourceMetadata {
+  DataSource source = 1;
+  string file_path = 2;
+  DataFormat format = 3;
+  google.protobuf.Timestamp last_modified = 4;
+  uint32 size = 5;
+}
+
+//
+// Data exchange messages
+//
+
+// Request to pull metadata for a data source
+message OrbRelayDataMetadataPull { DataReference reference = 1; }
+
+// Request to pull full data from a data source
+message OrbRelayDataExchangePull { DataReference reference = 1; }
+
+// Provide metadata for a data source
+message OrbRelayDataMetadataPush { DataSourceMetadata source_metadata = 1; }
+
+// Provide full data from a data source
+message OrbRelayDataExchangePush {
+  DataSourceMetadata metadata = 1;
+  bytes data = 2; // bytes will be encoded in the format specified in metadata.format
+}
diff --git a/proto/relay.proto b/proto/relay.proto
index 35676b7..221e03e 100644
--- a/proto/relay.proto
+++ b/proto/relay.proto
@@ -4,6 +4,7 @@ package relay;
 
 import "config/backend.proto";
 import "config/orb.proto";
+import "dataxchg/dataxchg.proto";
 import "self_serve/app.proto";
 import "self_serve/orb.proto";
 
@@ -54,6 +55,7 @@ message OrbCommand {
   oneof command {
     selfserve.OrbStartSelfServeSignupCommand orb_start_self_serve_signup_command = 1;
     config.OrbReceiveConfigUpdate orb_receive_config_update = 2;
+    dataxchg.OrbRelayDataExchangePull orb_relay_data_exchange_pull = 3;
   }
 }
 
@@ -63,6 +65,7 @@ message OrbEvent {
     selfserve.OrbSelfServeSessionStartedEvent orb_self_serve_session_started_event = 2;
     selfserve.OrbSignupStartedEvent orb_signup_started_event = 3;
     selfserve.OrbSignupCompletedEvent orb_signup_completed_event = 4;
+    dataxchg.OrbRelayDataExchangePush orb_relay_data_exchange_push = 5;
   }
 }
 
@@ -73,6 +76,7 @@ message AppCommand {
     selfserve.NotifyAppSignupStartedCommand notify_app_signup_started_command = 3;
     selfserve.AppReceiveSignupResultCommand app_receive_signup_result_command = 4;
     selfserve.AppShowStartSignupButtonCommand app_show_start_signup_button_command = 5;
+    dataxchg.OrbRelayDataExchangePull orb_relay_data_exchange_pull = 6;
   }
 }
 
@@ -81,17 +85,20 @@ message AppEvent {
     AppConnectRequestEvent app_connect_request_event = 1;
     selfserve.AppRequestStartSelfServeFlowEvent app_request_start_self_serve_flow_event = 2;
     selfserve.AppRequestStartSignupEvent app_request_start_signup_event = 3;
+    dataxchg.OrbRelayDataExchangePush orb_relay_data_exchange_push = 4;
   }
 }
 
 message BackendEvent {
   oneof event {
     config.OrbUpdateConfigRequest orb_update_config_request = 1;
+    dataxchg.OrbRelayDataExchangePull orb_relay_data_exchange_pull = 2;
   }
 }
 
 message BackendCommand {
   oneof command {
     config.OrbUpdateConfigResponse orb_update_config_response = 1;
+    dataxchg.OrbRelayDataExchangePush orb_relay_data_exchange_push = 2;
   }
 }
diff --git a/rust/Cargo.toml b/rust/Cargo.toml
index 677c326..394a7ae 100644
--- a/rust/Cargo.toml
+++ b/rust/Cargo.toml
@@ -12,6 +12,7 @@ server = []
 
 [dependencies]
 prost = "0.12.6"
+prost-types = "0.12.6"
 tonic = "0.11.0"
 
 [build-dependencies]
diff --git a/rust/build.rs b/rust/build.rs
index d10aa52..8b8d44d 100644
--- a/rust/build.rs
+++ b/rust/build.rs
@@ -13,6 +13,7 @@ fn main() {
                 "../proto/self_serve/orb.proto",
                 "../proto/config/backend.proto",
                 "../proto/config/orb.proto",
+                "../proto/dataxchg/dataxchg.proto",
             ],
             &["../proto"],
         )
diff --git a/rust/src/lib.rs b/rust/src/lib.rs
index a574b61..6de5dc3 100644
--- a/rust/src/lib.rs
+++ b/rust/src/lib.rs
@@ -12,3 +12,7 @@ pub mod selfserve {
 pub mod config {
     tonic::include_proto!("config");
 }
+
+pub mod dataxchg {
+    tonic::include_proto!("dataxchg");
+}