diff --git a/briar-api/src/org/briarproject/api/invitation/InvitationConstants.java b/briar-api/src/org/briarproject/api/invitation/InvitationConstants.java
index e858fe9c0b485c5f673efc7c83b7050d7142642f..ee3e7d93dd02f7e70b3fd478a62ee97dd8e9aed3 100644
--- a/briar-api/src/org/briarproject/api/invitation/InvitationConstants.java
+++ b/briar-api/src/org/briarproject/api/invitation/InvitationConstants.java
@@ -1,5 +1,6 @@
 package org.briarproject.api.invitation;
 
+
 public interface InvitationConstants {
 
 	long CONNECTION_TIMEOUT = 30 * 1000; // Milliseconds
@@ -7,8 +8,4 @@ public interface InvitationConstants {
 	long CONFIRMATION_TIMEOUT = 60 * 1000; // Milliseconds
 
 	int CODE_BITS = 19; // Codes must fit into six decimal digits
-
-	int HASH_LENGTH = 48; // Bytes
-
-	int MAX_PUBLIC_KEY_LENGTH = 97; // Bytes
 }
diff --git a/briar-core/src/org/briarproject/invitation/Connector.java b/briar-core/src/org/briarproject/invitation/Connector.java
index 1fa00401217ad5717afd9f7f086adc47bb916d6f..af944d5d7682b217e1ac3c3eef05c354700fbd31 100644
--- a/briar-core/src/org/briarproject/invitation/Connector.java
+++ b/briar-core/src/org/briarproject/invitation/Connector.java
@@ -3,12 +3,12 @@ package org.briarproject.invitation;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.api.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
+import static org.briarproject.api.AuthorConstants.MAX_PUBLIC_KEY_LENGTH;
 import static org.briarproject.api.AuthorConstants.MAX_SIGNATURE_LENGTH;
 import static org.briarproject.api.TransportPropertyConstants.MAX_PROPERTIES_PER_TRANSPORT;
 import static org.briarproject.api.TransportPropertyConstants.MAX_PROPERTY_LENGTH;
 import static org.briarproject.api.TransportPropertyConstants.MAX_TRANSPORT_ID_LENGTH;
 import static org.briarproject.api.invitation.InvitationConstants.CONNECTION_TIMEOUT;
-import static org.briarproject.api.invitation.InvitationConstants.HASH_LENGTH;
 
 import java.io.IOException;
 import java.security.GeneralSecurityException;
@@ -23,13 +23,13 @@ import java.util.Map.Entry;
 import java.util.logging.Logger;
 
 import org.briarproject.api.Author;
-import org.briarproject.api.AuthorConstants;
 import org.briarproject.api.AuthorFactory;
 import org.briarproject.api.ContactId;
 import org.briarproject.api.FormatException;
 import org.briarproject.api.LocalAuthor;
 import org.briarproject.api.TransportId;
 import org.briarproject.api.TransportProperties;
+import org.briarproject.api.UniqueId;
 import org.briarproject.api.crypto.CryptoComponent;
 import org.briarproject.api.crypto.KeyManager;
 import org.briarproject.api.crypto.KeyPair;
@@ -40,7 +40,6 @@ import org.briarproject.api.crypto.Signature;
 import org.briarproject.api.db.DatabaseComponent;
 import org.briarproject.api.db.DbException;
 import org.briarproject.api.db.NoSuchTransportException;
-import org.briarproject.api.invitation.InvitationConstants;
 import org.briarproject.api.messaging.Group;
 import org.briarproject.api.messaging.GroupFactory;
 import org.briarproject.api.plugins.ConnectionManager;
@@ -132,8 +131,8 @@ abstract class Connector extends Thread {
 	}
 
 	protected byte[] receivePublicKeyHash(Reader r) throws IOException {
-		byte[] b = r.readBytes(HASH_LENGTH);
-		if(b.length < HASH_LENGTH) throw new FormatException();
+		byte[] b = r.readBytes(UniqueId.LENGTH);
+		if(b.length < UniqueId.LENGTH) throw new FormatException();
 		if(LOG.isLoggable(INFO)) LOG.info(pluginName + " received hash");
 		return b;
 	}
@@ -147,7 +146,7 @@ abstract class Connector extends Thread {
 
 	protected byte[] receivePublicKey(Reader r) throws GeneralSecurityException,
 	IOException {
-		byte[] b = r.readBytes(InvitationConstants.MAX_PUBLIC_KEY_LENGTH);
+		byte[] b = r.readBytes(MAX_PUBLIC_KEY_LENGTH);
 		keyParser.parsePublicKey(b);
 		if(LOG.isLoggable(INFO)) LOG.info(pluginName + " received key");
 		return b;
@@ -203,7 +202,7 @@ abstract class Connector extends Thread {
 			throws GeneralSecurityException, IOException {
 		// Read the name, public key and signature
 		String name = r.readString(MAX_AUTHOR_NAME_LENGTH);
-		byte[] publicKey = r.readBytes(AuthorConstants.MAX_PUBLIC_KEY_LENGTH);
+		byte[] publicKey = r.readBytes(MAX_PUBLIC_KEY_LENGTH);
 		byte[] sig = r.readBytes(MAX_SIGNATURE_LENGTH);
 		if(LOG.isLoggable(INFO)) LOG.info(pluginName + " received pseudonym");
 		// Verify the signature