модель движения пуассона ns3

Я пытаюсь выучить ns3 и пытаюсь изменить один из примеров, используя onofApplication для генерации Vbr вместо Cbr, но код не работает, и я не знаю почему, не могли бы вы мне помочь, пожалуйста?

#include "ns3/core-module.h"#include "ns3/network-module.h"#include "ns3/csma-module.h"#include "ns3/internet-module.h"#include "ns3/point-to-point-module.h"#include "ns3/applications-module.h"#include "ns3/ipv4-global-routing-helper.h"#include "ns3/random-variable.h"#include "ns3/socket-factory.h"#include "ns3/udp-socket-factory.h"#include "ns3/on-off-helper.h"#include "ns3/nstime.h"

using namespace ns3;

NS_LOG_COMPONENT_DEFINE ("SecondScriptExample");

int
main (int argc, char *argv[])
{
bool verbose = true;
uint32_t nCsma = 3;

CommandLine cmd;
cmd.AddValue ("nCsma", "Number of \"extra\" CSMA nodes/devices", nCsma);
cmd.AddValue ("verbose", "Tell echo applications to log if true", verbose);

cmd.Parse (argc,argv);

if (verbose)
{
LogComponentEnable ("UdpEchoClientApplication", LOG_LEVEL_INFO);
LogComponentEnable ("UdpEchoServerApplication", LOG_LEVEL_INFO);
}

nCsma = nCsma == 0 ? 1 : nCsma;

NodeContainer p2pNodes;
p2pNodes.Create (2);

NodeContainer csmaNodes;
csmaNodes.Add (p2pNodes.Get (1));
csmaNodes.Create (nCsma);

PointToPointHelper pointToPoint;
pointToPoint.SetDeviceAttribute ("DataRate", StringValue ("5Mbps"));
pointToPoint.SetChannelAttribute ("Delay", StringValue ("2ms"));

NetDeviceContainer p2pDevices;
p2pDevices = pointToPoint.Install (p2pNodes);

CsmaHelper csma;
csma.SetChannelAttribute ("DataRate", StringValue ("100Mbps"));
csma.SetChannelAttribute ("Delay", TimeValue (NanoSeconds (6560)));

NetDeviceContainer csmaDevices;
csmaDevices = csma.Install (csmaNodes);

InternetStackHelper stack;
stack.Install (p2pNodes.Get (0));
stack.Install (csmaNodes);

Ipv4AddressHelper address;
address.SetBase ("10.1.1.0", "255.255.255.0");
Ipv4InterfaceContainer p2pInterfaces;
p2pInterfaces = address.Assign (p2pDevices);

address.SetBase ("10.1.2.0", "255.255.255.0");
Ipv4InterfaceContainer csmaInterfaces;
csmaInterfaces = address.Assign (csmaDevices);

UdpEchoServerHelper echoServer (9);

ApplicationContainer serverApps = echoServer.Install (csmaNodes.Get (nCsma));
serverApps.Start (Seconds (1.0));
serverApps.Stop (Seconds (10.0));

OnOffHelper onOffAP ("ns3::UdpSocketFactory", csmaInterfaces.GetAddress(nCsma));
onOffAP.SetAttribute("PacketSize", UintegerValue(1024));
onOffAP.SetAttribute("OffTime",RandomVariableValue(ExponentialVariable(0.01)));
// the packet arrivalrate on AP side is 100 pkt/sec, so we set mean value as 1/100
onOffAP.SetAttribute("OnTime",RandomVariableValue(ConstantVariable(0.0001583)));
// the constanttime for sending one packet
onOffAP.SetAttribute("DataRate", StringValue ("54Mbps"));

// UdpEchoClientHelper echoClient (csmaInterfaces.GetAddress (nCsma), 9);
//echoClient.SetAttribute ("MaxPackets", UintegerValue (1));
//echoClient.SetAttribute ("Interval", TimeValue (Seconds (1.0)));
//echoClient.SetAttribute ("PacketSize", UintegerValue (1024));

ApplicationContainer clientApps = onOffAP.Install (p2pNodes.Get (0));
clientApps.Start (Seconds (2.0));
clientApps.Stop (Seconds (10.0));

Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

pointToPoint.EnablePcapAll ("second");
csma.EnablePcap ("second", csmaDevices.Get (1), true);

Simulator::Run ();
Simulator::Destroy ();
return 0;
}

и я получаю эту ошибку

msg="Invalid value for attribute set (OffTime) on ns3::OnOffApplication", file=../src/core/model/object-factory.cc, line=75
libc++abi.dylib: terminate called without an active exception