diff --git a/data/avro-schema/src/main/resources/avro/net/corda/data/p2p/state/SessionState.avsc b/data/avro-schema/src/main/resources/avro/net/corda/data/p2p/state/SessionState.avsc
new file mode 100644
index 0000000000..a1cc1a4fe3
--- /dev/null
+++ b/data/avro-schema/src/main/resources/avro/net/corda/data/p2p/state/SessionState.avsc
@@ -0,0 +1,17 @@
+{
+  "type": "record",
+  "name": "SessionState",
+  "namespace": "net.corda.data.p2p.state",
+  "fields": [
+    {
+      "doc": "The message.",
+      "name": "message",
+      "type": "net.corda.data.p2p.LinkOutMessage"
+    },
+    {
+      "doc": "The encrypted session data.",
+      "name": "encryptedSessionData",
+      "type": "bytes"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/gradle.properties b/gradle.properties
index 5cde18bd12..53bbd4f054 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -5,7 +5,7 @@ cordaProductVersion = 5.2.0
 # NOTE: update this each time this module contains a breaking change
 ## NOTE: currently this is a top level revision, so all API versions will line up, but this could be moved to
 ##   a per module property in which case module versions can change independently.
-cordaApiRevision = 18
+cordaApiRevision = 19
 
 # Main
 kotlin.stdlib.default.dependency = false