Re: [netext] Review of I-D: draft-ietf-netext-pd-pmip6-06

["Sri Gundavelli (sgundave)" <[e-mail]>]

Hi Raj,

Inline …

From: Basavaraj Patil <[e-mail]<mailto:[e-mail]>>
Date: Wednesday, May 22, 2013 12:49 PM
To: Sri Gundavelli <[e-mail]<mailto:[e-mail]>>
Cc: "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>, "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>, "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>
Subject: Re: [netext] Review of I-D: draft-ietf-netext-pd-pmip6-06

Inline:


On Mon, May 20, 2013 at 10:26 AM, Sri Gundavelli (sgundave) <[e-mail]<mailto:[e-mail]>> wrote:
Hi Raj,


Adding to what carlos said. Just one clarification.



On 5/20/13 8:04 AM, "Carlos Jesús Bernardos Cano" <[e-mail]<mailto:[e-mail]>> wrote:



>> 5. In Sec 4.4.1, step 4:
>>    "If the mobile access
>>         gateway does not know the delegated prefix(es), then the
>>         delegated mobile network prefix in the DMNP option(s) MUST be
>>         set to the unspecified IPv6 address "::", "
>>
>>
>> How would the MAG know the delegated prefix(es)? Unless it is
>> just renewing the assigned prefix(es)?


The prefixes can be statically configured in the policy profile. Typically
mobile networks are statically configured (but registered with the LMA) as
we don't want the prefixes to disappear if the egress link goes down and
that will result in local communication between the hosts to break. So,
the prefixes are statically provisioned in the mobile network. But,
mobility support comes up only when there is active session with LMA
enabling the forwarding.

If the MAG knows the prefixes, it can indicate them in the DMNP option.
If the MAG does not know the prefixes,  it will carry a NULL value.
LMA assigns them based on what is in the BCE state.

This is consistent with how the home address (IPv4 HoA, HNP) options are
carried in PMIP signaling messages.


Raj>  What does this mean: "Typically
mobile networks are statically configured (but registered with the LMA)...."?

Also: "So,
the prefixes are statically provisioned in the mobile network."

Would be good if you can clarify since you have a view or interpretation that I am not sure everyone is in sync with.


[Sri] I'm just saying, the subnets (DMNP's) are configured manually in the mobile network. But, those subnets belong to the LMA from routing point of view. This is almost like a static IP configuration.
There is also the other approach, every thing happens dynamically, the prefix is obtained from the LMA/MAG and then gets configured in the mobile network.
In most deployments, IMO, static configuration is preferred as they don't want the networks/prefixes to disappear, if the LMA is not reachable and the PMIP tunnel goes down. There won't be IP mobility or external reachability, but there will be internal node to node communication.

Regards
Sri