Protocol Buffers will be used for the wire protocol. As a quick test it's now used to serialize transport details when creating an invitation.

api/net/sf/briar/api/db/DatabaseComponent.java

@@ -59,6 +59,9 @@ public interface DatabaseComponent {
 	/** Returns the set of groups to which the user subscribes. */
 	Set<GroupId> getSubscriptions() throws DbException;
 
+	/** Returns the local transport details. */
+	Map<String, String> getTransports() throws DbException;
+
 	/** Returns the transport details for the given contact. */
 	Map<String, String> getTransports(ContactId c) throws DbException;
 

api/net/sf/briar/api/protocol/Transport.proto

@@ -0,0 +1,13 @@
+package protocol;
+
+option java_package = "net.sf.briar.api.protocol";
+
+message TransportDetails {
+
+	message TransportDetail {
+		required string key = 1;
+		optional string value = 2;
+	}
+
+	repeated TransportDetail details = 1;
+}