java.net.SocketException: Connection reset

*hi , i want to make telnet connection some devices . i m able to connect cisco and juniper devices ,however, when send quit command to exit huawei devices my code throws Exception in thread "main" java.net.SocketException: Connection reset. here is part of mycode :

boolean passok=false;
    boolean showipok=false;
    boolean exit=false;
    boolean quit=false;
    boolean usernmok=false;



        byte[] buff = new byte[1024];
        int ret_read = 0;

        do
        {
            ret_read = instr.read(buff);
            if(ret_read > 0)

            {

                burak=new String(buff, 0, ret_read);
                System.out.print(burak);


                //system username isterse 
                if(burak.indexOf("Username:")!=-1 && usernmok==false){

                    outstr.write(("username\n").getBytes());
                    outstr.flush();
                    usernmok=true;


                }



                //username gönderildikten sonra password gönderiliyor
                if(burak.indexOf("Password:")!=-1 && passok==false && usernmok==true)
                {

                    outstr.write(("password"+"\n").getBytes());

                    outstr.flush();


                    passok=true;

                }






                    if(showipok==false && passok==true){
                        //komut yolla





                        outstr.write("display ospf peer brief\n".getBytes());

                        outstr.flush();





                        showipok=true;

                    }




                if(showipok==true&& exit==false&& passok==true )
                {
                    //System.out.print("quit");
                        outstr.write("quit\n".getBytes());

                    outstr.flush();
                    exit=true;
                }


}

            }



        }
        while (ret_read >= 0);

im using apache common telnet library . i tried set timeout for the connection and then it throws timeout exception.I faced this problem in only huawei devices. Please give me some advices thanks.