RE: [mobile-ip] Re: FW: I-D ACTION:draft-tsirtsis-dsmip-problem-0 0.txt

 > > => As I described earlier, double encapsulation is one 
 > > option, there are others. The aim is not necessarily 
 > > to provide a trivial solution at all cost (it's obviously
 > > your aim but not mine). If you read the mipv4 solution
 > > (draft-tsirtsis) you can see that it's possible, but there
 > > is a need for a more BW-efficient solution.
 > 
 > Obviously, the problem statement should elaborate why double 
 > encapsulation 
 > does not solve the problem.

=> Reverse tunnelling and BW efficiency.


 > >  > > The same goes for traffic sent from the MN using 
 > >  > 2002:HADDR_v4::/48. 
 > >  > 
 > >  > Works equally well, as above.
 > > 
 > > => No it doesn't. How does the MN reverse tunnel to the
 > > HA? MIPv4 does not assume reverse tunnelling.
 > 
 > It has worked just fine for me w/ Dynamics 
 > (http://www.cs.hut.fi/Research/Dynamics/), AFAIR.
 > 
 > Are you saying that mobile nodes do not tunnel back to the 
 > HA themselves, 
 > just (optionally) rely on the FA's doing it?

=> Yes. I don't know what you did with
the Dynamics SW.

 > > => I don't understand how you assume that 6-to-4 provides
 > > bidirectional communication... This is why I think the HA
 > > is a good TEP because it's there, doesn't assume 6-to-4
 > > relays, and doesn't assume that the CNs have 6-to-4 addresses.
 > 
 > If you're worried about bidir communication, all you have to 
 > do is to give 
 > the HA also a 6to4 address: then 6to4 gives you 
 > bidirectionality as well.

=> what makes the MN reverse tunnel a packet sent to an 
IPv6 address to an IPv4 address?

 > >  > > But there is a more 
 > >  > > BW effifcient scenario that would require some assistance 
 > >  > > from the FA. Both options are explained in the solutions
 > >  > > draft (MIPv4 one) that George sent to the MIP mailing list.
 > >  > 
 > >  > Bandwidth efficiency is just ONE trade-off here.  
 > > 
 > > => Ah, one important trade-off! If you ask anyone deploying
 > > or working with a WWAN how important BW is, they'll
 > > choose it over simplicity anytime.
 > 
 > You may have different WWAN's in mind, but I disagree.  For 
 > example 802.11 

=> I said WWAN not WLAN. 


Hesham