diff --git a/nodejs-client/src/dsn/dsn_types.js b/nodejs-client/src/dsn/dsn_types.js
index ab3570589e..d7e1a32501 100644
--- a/nodejs-client/src/dsn/dsn_types.js
+++ b/nodejs-client/src/dsn/dsn_types.js
@@ -257,26 +257,38 @@ rpc_address.prototype.equals = function(other){
 };
 
 // TODO(yingchun): host_port is now just a place holder and not well implemented, need improve it
+// Error code enum
+var host_port_type = {
+    HOST_TYPE_INVALID : 0,
+    HOST_TYPE_IPV4 : 1,
+    HOST_TYPE_GROUP : 2
+};
 var host_port = function(args) {
     this.host = null;
     this.port = 0;
+    this.type = host_port_type.HOST_TYPE_INVALID;
     if(args && args.host){
         this.host = args.host;
     }
     if(args && args.port){
         this.port = args.port;
     }
+    if(args && args.type){
+        this.type = args.type;
+    }
 };
 
 host_port.prototype = {};
 host_port.prototype.read = function(input){
     this.host = input.readBinary();
     this.port = input.readI16();
+    this.type = input.readByte();
 };
 
 host_port.prototype.write = function(output){
     output.writeBinary(this.host);
     output.writeI16(this.port);
+    output.writeByte(this.type);
 };
 
 //value, calculate by app_id and partition index