Populate ARP cache (for ns-3 Wi-Fi simulations)

PopulateARPcache.cc

// Function to populate ARP cache of all nodes in ns-3, prevents ARP blocking in Wi-Fi networks
// Execute after assigning IP addresses
// Author: Pavel Boyko?
// https://groups.google.com/d/msg/ns-3-users/L_ZfZ9L1_b0/dCuzc859ENcJ

void PopulateARPcache () {
	Ptr<ArpCache> arp = CreateObject<ArpCache> ();
	arp->SetAliveTimeout (Seconds (3600 * 24 * 365) );

	for (NodeList::Iterator i = NodeList::Begin (); i != NodeList::End (); ++i)
	{
		Ptr<Ipv4L3Protocol> ip = (*i)->GetObject<Ipv4L3Protocol> ();
		NS_ASSERT (ip !=0);
		ObjectVectorValue interfaces;
		ip->GetAttribute ("InterfaceList", interfaces);

		for (ObjectVectorValue::Iterator j = interfaces.Begin (); j != interfaces.End (); j++)
		{
			Ptr<Ipv4Interface> ipIface = (*j).second->GetObject<Ipv4Interface> ();
			NS_ASSERT (ipIface != 0);
			Ptr<NetDevice> device = ipIface->GetDevice ();
			NS_ASSERT (device != 0);
			Mac48Address addr = Mac48Address::ConvertFrom (device->GetAddress () );

			for (uint32_t k = 0; k < ipIface->GetNAddresses (); k++)
			{
				Ipv4Address ipAddr = ipIface->GetAddress (k).GetLocal();
				if (ipAddr == Ipv4Address::GetLoopback ())
					continue;

				ArpCache::Entry *entry = arp->Add (ipAddr);
				Ipv4Header ipv4Hdr;
				ipv4Hdr.SetDestination (ipAddr);
				Ptr<Packet> p = Create<Packet> (100);
				entry->MarkWaitReply (ArpCache::Ipv4PayloadHeaderPair (p, ipv4Hdr));
				entry->MarkAlive (addr);
			}
		}
	}

	for (NodeList::Iterator i = NodeList::Begin (); i != NodeList::End (); ++i)
	{
		Ptr<Ipv4L3Protocol> ip = (*i)->GetObject<Ipv4L3Protocol> ();
		NS_ASSERT (ip !=0);
		ObjectVectorValue interfaces;
		ip->GetAttribute ("InterfaceList", interfaces);

		for (ObjectVectorValue::Iterator j = interfaces.Begin (); j != interfaces.End (); j ++)
		{
			Ptr<Ipv4Interface> ipIface = (*j).second->GetObject<Ipv4Interface> ();
			ipIface->SetAttribute ("ArpCache", PointerValue (arp) );
		}
	}
}