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

[Tsirtsis George <G.Tsirtsis@flarion.com>]

Inline...

-----Original Message-----
From: Pekka Savola [mailto:pekkas@netcore.fi] 
Sent: Tuesday, August 05, 2003 9:47 AM
To: Tsirtsis George
Cc: 'Alain Durand'; Mobile-Ip (mobile-ip@sunroof.eng.sun.com);
v6ops@ops.ietf.org
Subject: RE: [mobile-ip] Re: FW: I-D ACTION:draft-tsirtsis-dsmip-problem-0
0.txt

...

> We can always complicate things but why not deal with the simple and 
> by far most important issue.
> 
> Today Mobile IP signals HoA to CoA bindings of the same version 
> resulting in either IPv4 over IPv4 encapsulation or IPv6 over IPv6 
> encapsulation.
> 
> All I am suggesting is that Mobile IP should be able to signal HoA to 
> CoA bindings of different versions so that IPv4 over IPv6 
> encapsulation or IPv4 over IPv6 encapsulation is also possible.

And what benefit, exactly, would the change in encapsulation have?  The 
Home Agents and the nodes would still have to support both versions, you 
would just end up with two Mobile IP protocols which (to some extent) 
supported both IPv4 and IPv6.

GT> Running IPv6 over MIPv4 today means that you need to somehow encapsulate
IPv6 over the existing IPv4 over IPv4 tunnel created by MIPv4 i.e.: double
tunnel. With the suggested approach MIPv4 is itself able to create IPv6 over
IPv4 tunnels as well as IPv4 over IPv4 tunnels i.e.: single tunneling. And
yes, if we extend both MIPv4 and MIPv6 with dual stack extensions then we
will have two protocols but a network or a mobile can choose to utilize only
one of the two which will take it long way towards ubiquitous connectivity.

Looking briefly at the conclusions section gives me an impression you want a
transport-protocol independent MobileIP++ that's agnostic of IPv4 or IPv6,
with an understanding that you would not have to solve the problem of the
direct communication between IPv6-only and IPv4-only nodes.

GT> I am clearly not suggesting transport independency since I am basing the
extension on transport dependant MIPv4 and MIPv6. I am merely suggesting
that these transport dependant protocols should be able to set up  version
independent tunnels

It seems like HIP fits the bill quite nicely, and would be architecturally 
better approach than trying to glue MIPv4 and MIPv6 together somehow.

GT>...with the addition that I view this as an *evolutionary* approach. The
extensions I am talking about are suitable for networks that already utilize
or want to utilize MIP (v4 or v6) for mobility management. 

GT> With respect, HIP has a long way to go before it becomes real and in any
case I have never seen how HIP is going to solve the mobility management
problem...if it does fantastic and the market I am sure will look at this
when it becomes available...in the mean time people are deploying Mobile IP.

Regards
George