diff --git a/src/Link.cpp b/src/Link.cpp
index 05dbc05..fcc8954 100644
--- a/src/Link.cpp
+++ b/src/Link.cpp
@@ -276,10 +276,11 @@ void Link::handshake() {
 void Link::prove() {
 	assert(_object);
 	DEBUGF("Link %s requesting proof", link_id().toHex().c_str());
-	Bytes signed_data =_object->_link_id + _object->_pub_bytes + _object->_sig_pub_bytes;
+	Bytes signalling_bytes = Link::signalling_bytes(_object->_mtu, _object->_mode);
+	Bytes signed_data = _object->_link_id + _object->_pub_bytes + _object->_sig_pub_bytes + signalling_bytes;
 	const Bytes signature(_object->_owner.identity().sign(signed_data));
 
-	Bytes proof_data = signature + _object->_pub_bytes;
+	Bytes proof_data = signature + _object->_pub_bytes + signalling_bytes;
 	// CBA LINK
 	// CBA TODO: Determine which approach is better, passing liunk to packet or passing _link_destination
 	Packet proof(*this, proof_data, Type::Packet::PROOF, Type::Packet::LRPROOF);
@@ -337,7 +338,7 @@ void Link::validate_proof(const Packet& packet) {
 				handshake();
 
 				_object->_establishment_cost += packet.raw().size();
-				Bytes signed_data = _object->_link_id + _object->_peer_pub_bytes + _object->_peer_sig_pub_bytes;
+				Bytes signed_data = _object->_link_id + _object->_peer_pub_bytes + _object->_peer_sig_pub_bytes + signalling_bytes;
 				const Bytes signature(packet_data.left(Type::Identity::SIGLENGTH/8));
 				
 				TRACEF("Link %s validating identity", link_id().toHex().c_str());
diff --git a/src/Transport.cpp b/src/Transport.cpp
index 372ff83..3dcef68 100644
--- a/src/Transport.cpp
+++ b/src/Transport.cpp
@@ -3,6 +3,7 @@
 #include "Reticulum.h"
 #include "Destination.h"
 #include "Identity.h"
+#include "Link.h"
 #include "Packet.h"
 #include "Interface.h"
 #include "Log.h"
@@ -2242,15 +2243,19 @@ using namespace RNS::Utilities;
 				// needs to be transported
 				if ((Reticulum::transport_enabled() || for_local_client_link || from_local_client) && _link_table.find(packet.destination_hash()) != _link_table.end()) {
 					TRACE("Handling link request proof...");
-					LinkEntry link_entry = (*_link_table.find(packet.destination_hash())).second;
+					LinkEntry& link_entry = (*_link_table.find(packet.destination_hash())).second;
 					if (packet.receiving_interface() == link_entry._outbound_interface) {
 						try {
-							if (packet.data().size() == (Type::Identity::SIGLENGTH/8 + Type::Link::ECPUBSIZE/2)) {
+							if (packet.data().size() == (Type::Identity::SIGLENGTH/8 + Type::Link::ECPUBSIZE/2) || packet.data().size() == (Type::Identity::SIGLENGTH/8 + Type::Link::ECPUBSIZE/2 + Type::Link::LINK_MTU_SIZE)) {
+								Bytes signalling_bytes;
+								if (packet.data().size() == (Type::Identity::SIGLENGTH/8 + Type::Link::ECPUBSIZE/2 + Type::Link::LINK_MTU_SIZE)) {
+									signalling_bytes = Link::signalling_bytes(Link::mtu_from_lp_packet(packet), Link::mode_from_lp_packet(packet));
+								}
 								Bytes peer_pub_bytes = packet.data().mid(Type::Identity::SIGLENGTH/8, Type::Link::ECPUBSIZE/2);
 								Identity peer_identity = Identity::recall(link_entry._destination_hash);
 								Bytes peer_sig_pub_bytes = peer_identity.get_public_key().mid(Type::Link::ECPUBSIZE/2, Type::Link::ECPUBSIZE/2);
 
-								Bytes signed_data = packet.destination_hash() + peer_pub_bytes + peer_sig_pub_bytes;
+								Bytes signed_data = packet.destination_hash() + peer_pub_bytes + peer_sig_pub_bytes + signalling_bytes;
 								Bytes signature = packet.data().left(Type::Identity::SIGLENGTH/8);
 
 								if (peer_identity.validate(signature, signed_data)) {