Subject: [DMM] clarifications on draft-chan-dmm-distributed-mobility-anchoring-01 - and 2 questions

From: Alexandru Petrescu <[email-masked]>
Date: Wed, 25 Mar 2015 18:41:34 -0500

Hello,

During yesterday's DMM meeting there were several clarification
questions on draft-chan-dmm-distributed-mobility-anchoring-01.

I talked this morning to Anthony, and I think there is a case.

The IP Anchor - we all know what is.  It typically anchors the HoA of
Mobile IPv6 protocol.  It is a Border Router or a Home Agent, or so.

The "Session IP" Anchor is new and deserves clarification.

The "Session IP Anchor" is actually a "Session Anchor".  If a session is
identified by an IP address (i.e. a brief web browsing session to the IP
address of a web server) then that's the Care-of Address; that is a
"Session IP Anchor" and it is typically an Access Router where that IP
address (CoA) is topologically correct.

On another hand, Sessions can be identified by something else than an IP
address.  For example, a TCP session is identified by a quad
IPsrc/IPdst/srcport/srcdst.  The anchor of this session may be something
else than the Access Router.  It could be for example an Application
Layer Gateway (ALG) like for example a HTTP proxy.

So we end up with two anchors: the "Address Anchor" and the "HTTP Proxy
Anchor".

A session can be identified by a SIP identifier as well (SIP - Session
Initiation Protocol).  In that case the "Session Anchor" would be a SIP
Server.

Following this presumably locator-identifier split, we can think about
this session to be for HIP, for SHIM6 and even DNS.  Each time there is
a different Session Anchor.

And this draft proposes to offer a double-level mobility which allows
changing the IP anchor or the session anchor without interrupting the
sessions.

That said, I wonder whether the IP Anchor of this draft supports
SUSTAINED, NOMADIC, FIXED kinds of addresses.

I also wonder whether the Alper's API draft supports SUSTAINED, NOMADIC,
FIXED attributes of IP addresses in the DNS.

Alex