function matperfClient_StartExp(varargin)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% options :
%       UDP/TCP single
%       UDP/TCP dualtest
%       UDP/TCP tradeoff
% usage : 
%       matperfClient_StartExp('UDP','10.96.94.199','dualtest')
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
tic;

UdpTcp  = 0; % UdpTcp is 1 when UDP and it is 2 when TCP
clear_set;

if strcmp(varargin(1),'UDP'),
    UdpTcp = 1;
    tmp_add = varargin(2);
elseif strcmp(varargin(1), 'TCP'),
    UdpTcp = 2;
    tmp_add = varargin(2);
end
% tells matlab what mode user wants to use. 
if strcmp(varargin(3), 'single'),
    mode = 1; % single
elseif strcmp(varargin(3), 'dualtest'),
    mode = 2; % dualtest
elseif strcmp(varargin(3), 'tradeoff'),
    mode = 3; % tradeoff
else
    return 
end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Ask server to generate & accept experiment
% 0 - experiment request
% 1 - trial request
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% In the below while loop, it will generate a udp packet that includese whether 
% the client is in UDP/TCP single, dualtest or trade off mode and asks the 
% server to get ready for the experiment. If the server successfully 
% recognizes the request and be ready, it will send 0 back to the client
% and matlab gets out of this while loop.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
udp = pnet('udpsocket', 3333);
packet = [0; UdpTcp; mode]; % prepares a package
while(1),
    pnet(udp,'write',packet);
    pnet(udp,'writepacket',char(tmp_add),3333); % sends a packet carrying signal 0.
    pnet(udp,'setreadtimeout',1.2); % wait for the response for 1.2 seconds
    len = pnet(udp,'readpacket');
    [address] = pnet(udp,'gethost');
    if len == 0 || len < 0, % if the client does not receive the response
        disp('server not responding...reasking to awknowledge');
        pnet('closeall');
        udp = pnet('udpsocket',3333);
        continue;
    elseif len >0,          % client has received a response. 
        data = pnet(udp,'read',1000,'double');
        if data == 0,
            disp('server approved experiment request');
        else
            disp('Wrong Code');
            continue
        end
        break;
    end
end
pnet('closeall');

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% calling the matperfClient_StartTrial(length, bandwidth, UdpTcp, mode)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% if need to define port #              %
% define here                           %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
reqport = 5001; % default               

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% if need to define time #              %
% define here                           %
  time = 30; % default                  %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
oneM = 1024 * 1024; % defined as 1 Mbits
tenM = 10 * oneM;
i = 1;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
oneWM = 1024 * 8;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% when UDP is selected, the client will run the two for loops with
% different values of bandwidth and length; and it will set the windows
% value to 0, which is not needed here. And after one trial, i and the port
% number will increment by 1 and used in next trial.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if UdpTcp == 1,
    windows = 0;
    for length = 200 :600: 1400
        for bandwidth = linspace(oneM,oneM * 50,50)
            matperfClient_StartTrial(length, windows, bandwidth, UdpTcp, mode, time,address,reqport)
            nem = sprintf('executed %d trial',i);
            i = i + 1;
            disp(nem);
        end
    end
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    % when TCP is selected, length and bandwidth are kept constant and only
    % window value is being changed and i and port number increment by 1 as
    % well.
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
elseif UdpTcp == 2,
    length = 0;
    bandwidth = 0;
    for windows = linspace(2* oneWM, 216* oneWM, 10)
        matperfClient_StartTrial(length, windows, bandwidth, UdpTcp, mode, time,address,reqport)
        nem = sprintf('executed %d trial',i);
        reqport = reqport + 1;
        i = i + 1;
        disp(nem);
    end
    
end
toker = toc;
disp(toker)
return