Re: [netext] comment on draft-ietf-netext-pmip6-lr-ps-00.txt

[Qin Wu <sunseawq at huawei.com>]

Hi,
Although RFC 5213 considers local routing, however it is focusing on only one limited scenario where two communciating MNs attach to the same MAG and there is no localized routing signaling to be specified to allow two communciating MNs locally routing.
Comparing with the section 6.10.3 of RFC 5213, what the abstract of I-D.ietf-netext-pmip6-lr-ps-00 is emphasizing is localized routing signaling design is not
considered in  the RFC5213. Therefore I think the abstract of I-D.ietf-netext-pmip6-lr-ps-00 has no conflict with what is described in the section 6.10.3 of RFC5213. As regarding the section 1, the only inconsistent text with the description of section 6.10.3 of RFC 5213 is
"
Even though two communicating MNs might be attached to the
same MAG or to different MAGs of the same local mobility domain,
packets will traverse the MNs' LMA(s).

"
therefore I would like suggest to remove this inconsistent text or reword this text  as
"
Even though two communicating MNs might be attached to the
same MAG or to different MAGs of the same local mobility domain,
packets *USUALLY* traverse the MNs' LMA(s) as well.
"
Any thoughts?

Regards!
-Qin
----- Original Message ----- 
From: "Glen Zorn" <gwz at net-zen.net>
To: <liebsch at nw.neclab.eu>; "'Qin Wu'" <sunseawq at huawei.com>; <sjjeong at etri.re.kr>
Cc: <netext at ietf.org>
Sent: Sunday, October 18, 2009 6:05 PM
Subject: comment on draft-ietf-netext-pmip6-lr-ps-00.txt


> The Abstract says:
>   In Proxy Mobile IPv6, mobile nodes are topologically
>   anchored at a Local Mobility Anchor, which forwards all data for
>   registered mobile nodes.  The set up and maintenance of localized
>   routing, which allows forwarding of data packets between mobile nodes
>   and correspondent nodes directly without involvement of the Local
>   Mobility Anchor in forwarding, is not considered. 
> and section 1 says:
>   The IETF has specified Proxy Mobile IPv6 (PMIPv6) [RFC5213] as the
>   base protocol for network-based localized mobility management
>   (NetLMM), which takes basic operation for registration, de-
>   registration and handover into account.  In scope of the base
>   protocol is the set up and maintenance of a forwarding tunnel between
>   an MN's Mobility Access Gateway (MAG) and its selected Local Mobility
>   Anchor (LMA).  Data packets will always traverse the MN's MAG and its
>   LMA, irrespective of the location of the MN's remote communication
>   endpoint.  Even though two communicating MNs might be attached to the
>   same MAG or to different MAGs of the same local mobility domain,
>   packets will traverse the MNs' LMA(s).
> 
> However, it appears that both these passages are incorrect, since section
> 6.10.3 of RFC 5213 both considers local routing and specifically permits it:
>   If there is data traffic between a visiting mobile node and a
>   correspondent node that is locally attached to an access link
>   connected to the mobile access gateway, the mobile access gateway MAY
>   optimize on the delivery efforts by locally routing the packets and
>   by not reverse tunneling them to the mobile node's local mobility
>   anchor.  The flag EnableMAGLocalRouting MAY be used for controlling
>   this behavior.  
>