[nemo] Re: DS-MIPv6 technicals

[Alexandru Petrescu <[e-mail]>]

Keiichi SHIMA wrote:
> Hi,
> 
> From: Alexandru Petrescu <[e-mail]> Subject: 
> Re: DS-MIPv6 technicals (waS: [nemo] NEMOv4 vs DS-MIPv6) Date: Thu, 
> 11 May 2006 14:10:57 +0200
> 
>> I'm not sure I understand.  The draft doesn't say at all that the 
>> BU can carry an IPv4 MNP that is not prefixing the HoA as well.
>> 
>> The option in BU is named "IPv4 home address option".  It's 
>> difficult to read it as a "IPv4 mobile network prefix" although 
>> technically speaking the IPv4 home address option contains an 
>> address/prefix length.
> 
> I agree.  I think the best way is to write your proposed text to 
> solve the above confusion and put it in the issue tracker.

I am not sure I can write something in the issue tracker until the
authors of the document agree.  I think they are responsible for the
issue tracker, no?

>>>> And about extending the IPv6 Prefix Table to support IPv4 MNP 
>>>> related to IPv4 HoA?
>>> What does this mean?  I don't understand why IPv6 prefix table 
>>> have to support IPv4 prefix...  (or are you talking about binding
>>>  IPv6 prefixes to IPv4 HoA?)
>> No, talking about MR's IPv4 HoA - IPv4 MNP.
>> 
>> The LFNs run IPv4-only, there are MNP (moving network prefixes) in 
>> the BU sent by MR to its HA.  In this case the MNP is IPv4.  HA 
>> should check that MR (its IPv4 Home Address) is allowed to use that
>>  particular MNP. This association is done in the prefix table.
> 
> I raised this problem as issue 59. 
> http://www.mip4.org/issues/tracker/mip6/issue59
> 
> Is this your concern?

My concern is about the text there:
> for 4.3. Home agent operations:
> 
> IPv4 packets delivered to the home agent must be forwarded using the
>  bi-directional tunnel to the corresponding mobile node which has 
> registered the same IPv4 prefix of the delivered packets as an IPv4 
> mobile network prefix.  IPv4 packets received from the bi-directional
>  tunnel created between the home agent and a mobile node must be 
> forwarded based on the routing information of the home agent, if the
>  prefix is registered as one of IPv4 mobile network prefixes of the 
> mobile node.

I am thinking about writing specific text about Prefix Table.  Not about
"routing information of the home agent".  Prefix Table is described both
in NEMOv6 and NEMOv4.

>> if the prefix is registered as one of IPv4 mobile network prefixes 
>> of the mobile node.

The MNP in the Prefix Table is not "registered" as if it were inserted
there upon reception of the BU.  The MNP in Prefix Table is
pre-configured in the HA.  When HA receives BU from MR it checks the MNP
and HoA in the BU against the MNP and HoA already in the Prefix Table.

The only thing I'm suggesting is to have a section titled "Prefix Table
for DS-MIPv6" that says that the Prefix Table may contain IPv6 HoA -
IPv6 MNP pairs, or IPv4 HoA - IPv4 MNP pairs, or IPv4-mapped IPv6 HoA...
etc.  There may be need of agreement of what exactly to put in the
Prefix Table.

Alex