Subject: Re: [MOBILE-IP] WG Last Call - draft-ietf-mobileip-3gwireless-ext -01.txt

From: Yingchun Xu <[email-masked]>
Date: Thu, 16 Dec 1999 10:23:57 -0600

Hi, Yuhara-san,
Your assertions are correct.

--Yingchun

Masanobu Yuhara <[email-masked]> on 12/15/99 09:22:49 PM

Please respond to Masanobu Yuhara <[email-masked]>

Sent by:  Masanobu Yuhara <[email-masked]>

To:   [email-masked]
cc:    (Yingchun Xu/MW/US/3Com)
Subject:  Re: [MOBILE-IP] WG Last Call -
      draft-ietf-mobileip-3gwireless-ext-01.txt

Thanks Pete, it gets much clearer.

The followings are what I understand now.
Are these assertions correct?

(1) HA in Fig.1 has nothing to do with this draft.

(2) HA is there because it may be used to deal with Macro-Mobility.
    In that case, Mobile-IP is nested. Inner Mobile-IP is for
    Micro-Mobility and outer Mobile-IP is for Macro-Mobility.
    The extension of this draft is for Micro-Mobility only.
    Macro-Mobility may and may not be used with Micro-Mobility.

(3) If (1) and (2) are correct, then we can summarize the situation as
    follows. MN, RNN, PDSN, HA are those in Fig.1 of the draft.

                +----------+----------+----------+
                | MIP's MN | MIP's FA | MIP's HA |
+---------------+----------+----------+----------+
|Micro-Mobility | RNN(*1)  |   RNN    |   PDSN   | (*1) RNN on behalf of MN
+---------------+----------+----------+----------+
|Macro-Mobility |   MN     |   PDSN   |   HA     |
+---------------+----------+----------+----------+
        Foreign Agent Care-of Addresses are used for both.

    PDSN is a HA for Micro-Mobility's point of view,
    but is also a FA for Macro-Mobility's point of view.

(4) When Micro- and Macro- Mobilities are used in combination,
    protocol stacks look like this:

[MN]      [  RNN   ]    [   PDSN    ]     [     HA     ]       [Corresponding
                                                                Node]

+----+                                                         +----+
|TCP |                                                         |TCP |
+----+                  +---+-------+     +-------+----+       +----+
|IP* |                  |IP*|  IP*  |     | IP*   |IP* |       |IP* |
+----+ . . . . . . . . .+---+-------+ . . +-------+----+ . . . +----+
|PPP |                  |PPP|MIP-tun|     |MIP-tun|
+----+    +----+---+    +---+-------+     +-------+
|RLP |    |RLP |GRE|    |GRE|  IP   |     |  IP   |
+----+    +----+---+    +---+-------+     +-------+
               |R-P|    |R-P|
               +---+    +---+
               | IP|    | IP|
               +---+    +---+

IP*: asterisk is attached to distinguish IP* from encapsulating IP.
MIP-tun: Mobile-IP tunnel (IP-in-IP or GRE or Minimal) from HA to FA (PDSN).
RLP: Radio Link Protocol
Link Layers and below are not shown (except RLP).

(5) This draft only covers the following part.

[MN]      [  RNN   ]    [   PDSN    ]

+----+                  +---+
|any |                  |any|
+----+                  +---+
|PPP |                  |PPP|
+----+    +----+---+    +---+
|RLP |    |RLP |GRE|    |GRE|
+----+    +----+---+    +---+
               |R-P|    |R-P|
               +---+    +---+
               | IP|    | IP|
               +---+    +---+

any: any protocol that can be carried over PPP.

-- masa

------
Masanobu Yuhara         [email-masked]
Fujitsu Laboratories Ltd.