diff --git a/src/remote/client/interface.cpp b/src/remote/client/interface.cpp
index 6a36da1a86..d4c88583f2 100644
--- a/src/remote/client/interface.cpp
+++ b/src/remote/client/interface.cpp
@@ -324,7 +324,7 @@ public:
 
 	unsigned int getTimeout(CheckStatusWrapper* status)
 	{
-		if (statement->rsr_rdb->rdb_port->port_protocol < PROTOCOL_VERSION15)
+		if (statement->rsr_rdb->rdb_port->port_protocol < PROTOCOL_STMT_TOUT)
 		{
 			status->setErrors(Arg::Gds(isc_wish_list).value());
 			return 0;
@@ -335,7 +335,7 @@ public:
 
 	void setTimeout(CheckStatusWrapper* status, unsigned int timeOut)
 	{
-		if (timeOut && statement->rsr_rdb->rdb_port->port_protocol < PROTOCOL_VERSION15)
+		if (timeOut && statement->rsr_rdb->rdb_port->port_protocol < PROTOCOL_STMT_TOUT)
 		{
 			status->setErrors(Arg::Gds(isc_wish_list).value());
 			return;
@@ -1795,7 +1795,7 @@ void Attachment::execWithCheck(CheckStatusWrapper* status, const string& stmt)
  *  case is when modern network server works with legacy engine.
  *
  **************************************/
-	if (rdb->rdb_port->port_protocol >= PROTOCOL_VERSION15)
+	if (rdb->rdb_port->port_protocol >= PROTOCOL_STMT_TOUT)
 	{
 		execute(status, NULL, stmt.length(), stmt.c_str(), SQL_DIALECT_CURRENT, NULL, NULL, NULL, NULL);
 
@@ -1820,7 +1820,7 @@ void Attachment::execWithCheck(CheckStatusWrapper* status, const string& stmt)
 
 unsigned int Attachment::getIdleTimeout(CheckStatusWrapper* status)
 {
-	if (rdb->rdb_port->port_protocol >= PROTOCOL_VERSION15)
+	if (rdb->rdb_port->port_protocol >= PROTOCOL_STMT_TOUT)
 		return getSingleInfo(status, fb_info_ses_idle_timeout_att);
 
 	status->setErrors(Arg::Gds(isc_wish_list).value());
@@ -1839,7 +1839,7 @@ void Attachment::setIdleTimeout(CheckStatusWrapper* status, unsigned int timeOut
 
 unsigned int Attachment::getStatementTimeout(CheckStatusWrapper* status)
 {
-	if (rdb->rdb_port->port_protocol >= PROTOCOL_VERSION15)
+	if (rdb->rdb_port->port_protocol >= PROTOCOL_STMT_TOUT)
 		return getSingleInfo(status, fb_info_statement_timeout_att);
 
 	status->setErrors(Arg::Gds(isc_wish_list).value());
diff --git a/src/remote/inet.cpp b/src/remote/inet.cpp
index 55c923c975..5a1273651d 100644
--- a/src/remote/inet.cpp
+++ b/src/remote/inet.cpp
@@ -621,7 +621,8 @@ rem_port* INET_analyze(ClntAuthBlock* cBlock,
 		REMOTE_PROTOCOL(PROTOCOL_VERSION12, ptype_lazy_send, 3),
 		REMOTE_PROTOCOL(PROTOCOL_VERSION13, ptype_lazy_send, 4),
 		REMOTE_PROTOCOL(PROTOCOL_VERSION14, ptype_lazy_send, 5),
-		REMOTE_PROTOCOL(PROTOCOL_VERSION15, ptype_lazy_send, 6)
+		REMOTE_PROTOCOL(PROTOCOL_VERSION15, ptype_lazy_send, 6),
+		REMOTE_PROTOCOL(PROTOCOL_VERSION16, ptype_lazy_send, 7)
 	};
 	fb_assert(FB_NELEM(protocols_to_try) <= FB_NELEM(cnct->p_cnct_versions));
 	cnct->p_cnct_count = FB_NELEM(protocols_to_try);
diff --git a/src/remote/os/win32/wnet.cpp b/src/remote/os/win32/wnet.cpp
index 6af1d51371..0b4bbcff01 100644
--- a/src/remote/os/win32/wnet.cpp
+++ b/src/remote/os/win32/wnet.cpp
@@ -173,7 +173,9 @@ rem_port* WNET_analyze(ClntAuthBlock* cBlock,
 		REMOTE_PROTOCOL(PROTOCOL_VERSION11, ptype_batch_send, 2),
 		REMOTE_PROTOCOL(PROTOCOL_VERSION12, ptype_batch_send, 3),
 		REMOTE_PROTOCOL(PROTOCOL_VERSION13, ptype_batch_send, 4),
-		REMOTE_PROTOCOL(PROTOCOL_VERSION14, ptype_batch_send, 5)
+		REMOTE_PROTOCOL(PROTOCOL_VERSION14, ptype_batch_send, 5),
+		REMOTE_PROTOCOL(PROTOCOL_VERSION15, ptype_batch_send, 6),
+		REMOTE_PROTOCOL(PROTOCOL_VERSION16, ptype_batch_send, 7)
 	};
 	fb_assert(FB_NELEM(protocols_to_try) <= FB_NELEM(cnct->p_cnct_versions));
 	cnct->p_cnct_count = FB_NELEM(protocols_to_try);
diff --git a/src/remote/os/win32/xnet.cpp b/src/remote/os/win32/xnet.cpp
index dd238f9a11..8533aee3ca 100644
--- a/src/remote/os/win32/xnet.cpp
+++ b/src/remote/os/win32/xnet.cpp
@@ -306,7 +306,8 @@ rem_port* XNET_analyze(ClntAuthBlock* cBlock,
 		REMOTE_PROTOCOL(PROTOCOL_VERSION12, ptype_batch_send, 3),
 		REMOTE_PROTOCOL(PROTOCOL_VERSION13, ptype_batch_send, 4),
 		REMOTE_PROTOCOL(PROTOCOL_VERSION14, ptype_batch_send, 5),
-		REMOTE_PROTOCOL(PROTOCOL_VERSION15, ptype_batch_send, 6)
+		REMOTE_PROTOCOL(PROTOCOL_VERSION15, ptype_batch_send, 6),
+		REMOTE_PROTOCOL(PROTOCOL_VERSION16, ptype_batch_send, 7)
 	};
 	fb_assert(FB_NELEM(protocols_to_try) <= FB_NELEM(cnct->p_cnct_versions));
 	cnct->p_cnct_count = FB_NELEM(protocols_to_try);
diff --git a/src/remote/protocol.cpp b/src/remote/protocol.cpp
index d9b8213fb5..4cc06be3e4 100644
--- a/src/remote/protocol.cpp
+++ b/src/remote/protocol.cpp
@@ -648,7 +648,7 @@ bool_t xdr_protocol(XDR* xdrs, PACKET* p)
 		}
 		{ // scope
 			rem_port* port = (rem_port*) xdrs->x_public;
-			if (port->port_protocol >= PROTOCOL_VERSION15)
+			if (port->port_protocol >= PROTOCOL_STMT_TOUT)
 				MAP(xdr_u_long, sqldata->p_sqldata_timeout);
 		}
 		DEBUG_PRINTSIZE(xdrs, p->p_operation);
diff --git a/src/remote/protocol.h b/src/remote/protocol.h
index bf7a24197d..c33ff0a818 100644
--- a/src/remote/protocol.h
+++ b/src/remote/protocol.h
@@ -84,9 +84,14 @@ const USHORT PROTOCOL_VERSION14	= (FB_PROTOCOL_FLAG | 14);
 
 // Protocol 15:
 //	- supports crypt key callback at connect phase
+
+const USHORT PROTOCOL_VERSION15 = (FB_PROTOCOL_FLAG | 15);
+
+// Protocol 16:
 //	- supports statement timeouts
 
-const USHORT PROTOCOL_VERSION15	= (FB_PROTOCOL_FLAG | 15);
+const USHORT PROTOCOL_VERSION16 = (FB_PROTOCOL_FLAG | 16);
+const USHORT PROTOCOL_STMT_TOUT = PROTOCOL_VERSION16;
 
 // Architecture types
 
diff --git a/src/remote/server/server.cpp b/src/remote/server/server.cpp
index 398fb66859..6bedf24301 100644
--- a/src/remote/server/server.cpp
+++ b/src/remote/server/server.cpp
@@ -1815,7 +1815,7 @@ static bool accept_connection(rem_port* port, P_CNCT* connect, PACKET* send)
 		protocol < end; protocol++)
 	{
 		if ((protocol->p_cnct_version >= PROTOCOL_VERSION10 &&
-			 protocol->p_cnct_version <= PROTOCOL_VERSION15) &&
+			 protocol->p_cnct_version <= PROTOCOL_VERSION16) &&
 			 (protocol->p_cnct_architecture == arch_generic ||
 			  protocol->p_cnct_architecture == ARCHITECTURE) &&
 			protocol->p_cnct_weight >= weight)