> Hello,
> Does anybody know if it is possible to assign /32 address to node (not
> necessarily using a helper - I'm aware of that bug), that will act as
> RID (Router ID).
> I'm basically looking for a sort of Loopback 0 interface (in Cisco
> terminology).
> I tried to achieve this goal doing something like this:

> void makerid(char *ipaddr, Ptr<Node> n) {
>  ObjectFactory m_queueFactory;
>  m_queueFactory.SetTypeId ("ns3::DropTailQueue");
>  ObjectFactory m_deviceFactory;
>  m_deviceFactory.SetTypeId ("ns3::CsmaNetDevice");
>  ObjectFactory m_channelFactory;
>  m_channelFactory.SetTypeId ("ns3::CsmaChannel");

>  Ptr<CsmaChannel> channel = m_channelFactory.Create ()-
> >GetObject<CsmaChannel> ();
>  Ptr<CsmaNetDevice> csmadevice =
> m_deviceFactory.Create<CsmaNetDevice> ();
>  csmadevice->SetAddress (Mac48Address::Allocate ());
>  csmadevice->SetName("rid");
>  n->AddDevice (csmadevice);
>  Ptr<Queue> queue = m_queueFactory.Create<Queue> ();
>  csmadevice->SetQueue (queue);
>  csmadevice->Attach (channel);

>  Ptr<NetDevice> device;
>  for(uint32_t i=0; i < n->GetNDevices(); i++) {
>    device = n->GetDevice(i);
>    if(device->GetName() == "rid") {
>      Ptr<Node> node = device->GetNode ();
>      NS_ASSERT_MSG (node, "Ipv4AddressHelper::Allocate(): Bad node");
>      Ptr<Ipv4> ipv4 = node->GetObject<Ipv4> ();
>      NS_ASSERT_MSG (ipv4, "Ipv4AddressHelper::Allocate(): Bad ipv4");
>      int32_t ifIndex = ipv4->FindInterfaceForDevice (device);
>      if (ifIndex == -1) {
>        ifIndex = ipv4->AddInterface (device);
>      }
>      NS_ASSERT_MSG (ifIndex >= 0, "Ipv4AddressHelper::Allocate():
> Interface index not found");
>      Ipv4Address ip(ipaddr);
>      ipv4->SetAddress (ifIndex, ip);
>      ipv4->SetNetworkMask (ifIndex, 0xffffffff);
>      //ipv4->SetNetworkMask (ifIndex, 0xffffff00);
>      ipv4->SetMetric (ifIndex, 1);
>      ipv4->SetUp (ifIndex);
>    }
>  }
> }

> However such a approach doesn't work. In short I tried to create an
> extra interface that would act as loopback.
> What I noticed is that if interface is created (doesn't matter which
> one i.e. p2p or csma), and has only one "client" i.e. nobody else is
> connected to that interface it doesn't work.

> For testing I'm using modified version of "first.cc", and what to
> achieve (topology below) is to have a transmission from router's A
> loopback 5.2.0.4  to router's B loopback 5.2.0.2 (in a similar way
> like multihop BGP works).

> RouterA(RID: 5.2.0.4) .73 <= p2p: 1.0.1.72/30 => .74 RouterB (RID:
> 5.2.0.2)

> One more thing. I'm using global route manage to populate routing
> tables.

> Your input is highly appreciated!