diff --git a/net/peer/context.go b/net/peer/context.go
index ca405012..4df39eaf 100644
--- a/net/peer/context.go
+++ b/net/peer/context.go
@@ -17,11 +17,13 @@ const (
 	contextKeyIdentity
 	contextKeyPeerAddr
 	contextKeyPeerClientVersion
+	contextKeyPeerProtoVersion
 )
 
 var (
-	ErrPeerIdNotFoundInContext   = errors.New("peer id not found in context")
-	ErrIdentityNotFoundInContext = errors.New("identity not found in context")
+	ErrPeerIdNotFoundInContext       = errors.New("peer id not found in context")
+	ErrProtoVersionNotFoundInContext = errors.New("proto version not found in context")
+	ErrIdentityNotFoundInContext     = errors.New("identity not found in context")
 )
 
 const CtxResponsiblePeers = "*"
@@ -42,6 +44,19 @@ func CtxWithPeerId(ctx context.Context, peerId string) context.Context {
 	return context.WithValue(ctx, contextKeyPeerId, peerId)
 }
 
+// CtxWithProtoVersion sets peer protocol version
+func CtxWithProtoVersion(ctx context.Context, version uint32) context.Context {
+	return context.WithValue(ctx, contextKeyPeerProtoVersion, version)
+}
+
+// CtxProtoVersion returns peer protocol version
+func CtxProtoVersion(ctx context.Context) (uint32, error) {
+	if protoVersion, ok := ctx.Value(contextKeyPeerProtoVersion).(uint32); ok {
+		return protoVersion, nil
+	}
+	return 0, ErrProtoVersionNotFoundInContext
+}
+
 // CtxPeerAddr returns peer address
 func CtxPeerAddr(ctx context.Context) string {
 	if p, ok := ctx.Value(contextKeyPeerAddr).(string); ok {
diff --git a/net/secureservice/secureservice.go b/net/secureservice/secureservice.go
index e8fb18c1..f5d89a5d 100644
--- a/net/secureservice/secureservice.go
+++ b/net/secureservice/secureservice.go
@@ -28,11 +28,13 @@ var (
 	// ProtoVersion 1 - version with yamux over tcp and quic
 	// ProtoVersion 2 - acl compatible version
 	// ProtoVersion 3 - acl with breaking changes / multiplayer
-	ProtoVersion = uint32(3)
+	// ProtoVersion 4 - new sync compatible version
+	NewSyncCompatibleVersion = uint32(4)
+	ProtoVersion             = uint32(5)
 )
 
 var (
-	compatibleVersions = []uint32{2, ProtoVersion}
+	compatibleVersions = []uint32{NewSyncCompatibleVersion, ProtoVersion}
 )
 
 func New() SecureService {
@@ -119,6 +121,7 @@ func (s *secureService) HandshakeInbound(ctx context.Context, conn io.ReadWriteC
 	cctx = peer.CtxWithPeerId(cctx, peerId)
 	cctx = peer.CtxWithIdentity(cctx, res.Identity)
 	cctx = peer.CtxWithClientVersion(cctx, res.ClientVersion)
+	cctx = peer.CtxWithProtoVersion(cctx, res.ProtoVersion)
 	return
 }
 
@@ -146,6 +149,7 @@ func (s *secureService) HandshakeOutbound(ctx context.Context, conn io.ReadWrite
 	cctx = peer.CtxWithPeerId(cctx, peerId)
 	cctx = peer.CtxWithIdentity(cctx, res.Identity)
 	cctx = peer.CtxWithClientVersion(cctx, res.ClientVersion)
+	cctx = peer.CtxWithProtoVersion(cctx, res.ProtoVersion)
 	return cctx, nil
 }