[support] FW: FW: DAD Delay too high?

[support at adhari.de]

Hi Arnaud,

I´m not sure if this problem have something to do with the DADRetransTimer. But I don´t know where to check this setting in order to exclude this possibilty.

Here are my configuration files: 

*********MobileNode*************

--------mip6d.conf:----------

   NodeConfig MN;
   DebugLevel 10;
   DoRouteOptimizationCN disabled;
   DoRouteOptimizationMN disabled;
   UseCnBuAck disabled;

   OptimisticHandoff disabled;
   MnRouterProbes 0;
   MnRouterProbeTimeout 0.02;
   MnMaxHaBindingLife 60;

  Interface "eth1" { 
    	Bid 100; 
	BidPriority 10;
	Reliable true;
   }

   MnHomeLink "eth1" {
        HomeAgentAddress 2001:a:b:0::1000;
        HomeAddress 2001:a:b:0::1/64 (2001:a:b:1::/64);
 }

   UseMnHaIPsec disabled;
   KeyMngMobCapability disabled;




*********HomeAgent*************

--------mip6d.conf:----------

   NodeConfig HA;
   DebugLevel 10;
   Interface "eth1";
   UseMnHaIPsec disabled;
   KeyMngMobCapability disabled;

--------Radvd.conf----------

   interface eth1
   {
        AdvSendAdvert on;
        MaxRtrAdvInterval 0.07;
        MinRtrAdvInterval 0.03;
        AdvIntervalOpt on;
        AdvHomeAgentFlag on;
        AdvHomeAgentInfo on;
        HomeAgentLifetime 1800;
        HomeAgentPreference 10;
        AdvMobRtrSupportFlag on;
        prefix 2001:a:b:0::1000/64
        {
                AdvRouterAddr on;
                AdvOnLink on;
                AdvAutonomous on;
        };
   };



*********Foreign Router************* (the MN tryes to connect to this Router)

--------Radvd.conf----------

   interface eth3
   {
        AdvSendAdvert on;
        MaxRtrAdvInterval 0.07;
        MinRtrAdvInterval 0.03;
        AdvIntervalOpt on;
        prefix 2001:a:f2:1::1/64
        {
                AdvRouterAddr on;
                AdvOnLink on;
                AdvAutonomous on;
        };
   };
   


Thx

Hakim





-----Original Message-----
From: Arnaud Ebalard [mailto:arno at natisbad.org] 
Sent: Donnerstag, 3. September 2009 13:03
To: support at adhari.de
Cc: support at jules.nautilus6.org; faqir.yousaf at uni-dortmund.de
Subject: Re: [support] DAD Delay too high?

Hi,

support at adhari.de writes:





> Hello everybody,
>
> I am performing MIPv6 handover measurements using UMIP-4.0
> on a debian system with a 2.6.29 kerne, and i am recording
> some unusually high values of handover latency (upto 8
> – 10 seconds) and am wondering if any one has an
> idea.
>
>
> I am performing a manual handover from HA to foreign
> network in a WLAN network (using Linksys APs), and I am
> capturing traffic using wireshark and I notice that after
> Router Discovery, the MN will understandably perform DAD
> test on the new CoA by sending Neighbor Solicitation
> messages (NS) I notice that the MN sends out two NS, one
> having the Link Local Address and the other the tentative
> CoA. They are send at times 5.255676 and 5.423619 sec
> respectively. 
>
> Now as per my understanding, the DAD test will take 1 sec
> and if it passes, the MN will assign the CoA and send a BU
> to the HA immediately. However I observe that the BU is sent
> almost 3 seconds later (i.e., at time 8.182842 sec. This can
> be seen in the wireshark log below:

Testing it on my Debian (2.6.30.5 kernel), the 3 NS (DAD for link-local
and 2 other unicast global addresses) are sent and a protected BU is
sent exactly 1 second after the emission of the last NS.

> Can any one explain as to why the MN spends so much time
> after the DAD test before sending out a BU message? Is this
> normal as I expect the BU to be sent almost 1 sec after the
> NS is sent out?

No, it is not normal. Can you post your configuration file?

> Where can I check the value of the DADRetransTimer
> parameter? Is there a possibility to manually set the
> DADRetransTimer parameter?

For DAD, there should be no retransmit IIRC. Is that question linked to
your problem?

Cheers,

a+