Subject: [netext] Default gateway attributes in to-be-rfc6572

From: jouni korhonen <[email-masked]>
Date: Mon, 16 Apr 2012 13:58:34 +0300

Folks,

Following the "tradition" we are back in WG asking for
few more things for ietf-draft-netext-radius-pmip6 ;) The
I-D was already in AUTH48, so this is not a shopping list
for all kinds of things but.. Since RFC5844 has a mobility
option for the IPv4 default gateway and the I-D & RFC5844
allow for signaling an IPv4 subnet instead of just /32 it
came apparent that we cannot assume all MAGs/LMAs could
figure out the default gateway address algorithmically for
all deployments. The assumption had been till AUTH48 phase
that the default gateway would just be the network_address+1
(and something else in case of RFC3021 /31). However, this
should be a deployment choice, not based on an assumption
that everybody will comply with network_address+1. Therefore,
we need two new attributes to explicitly state which is the
IPv4 default gateway address that has to be populated into
PMIPv6 signaling. 

Along with the addition of two new attributes, we also should
fix few other things that are seemingly not-too-right. Sorry for
a lengthy mail but there are several (trivial) changes all around
the document.

The proposed new text follows and quick comments are 
solicited:

4.20.  PMIP6-Home-IPv4-Gateway

   [RFC5844] specifies extensions to Proxy Mobile IPv6 protocol which
   enable IPv4 home address mobility support to the MN.  The PMIP6-Home-
   IPv4-Gateway attribute (Type value TBD1) is of type Address and
   contains the default gateway IPv4 address for the MN.  This address
   is populated into the PMIPv6 IPv4 Default-Router Address Option
   [RFC5844].  The address MUST belong to the subnet defined in the
   PMIP6-Home-IPv4-HoA attribute.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      Type     |   Length      |   Home IPv4 default gateway
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
               address             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:
      PMIP6-Home-IPv4-Gateway TBD1.

   Length:
      = 6 octets

   Home IPv4 default gateway address:
      This field is of type Address and contains a 4-octet IPv4 default
      gateway address.

4.21.  PMIP6-Visited-IPv4-Gateway

   [RFC5844] specifies extensions to Proxy Mobile IPv6 protocol which
   enable IPv4 home address mobility support to the MN.  The PMIP6-
   Visited-IPv4-Gateway attribute (Type value TBD2) is of type Address
   and contains the default gateway IPv4 address for the MN.  This
   address is populated into the PMIPv6 IPv4 Default-Router Address
   Option [RFC5844].  The address MUST belong to the subnet defined in
   the PMIP6-Visited-IPv4-HoA attribute.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      Type     |   Length      |  Visited IPv4 default gateway
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
               address             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:
      PMIP6-Visited-IPv4-Gateway TBD2.

   Length:
      = 6 octets

   Visited IPv4 default gateway address:
      This field is of type Address and contains a 4-octet IPv4 default
      gateway address.

5.2.  Table of Attributes

   The following table provides a guide to attributes that may be found
   in authentication and authorization RADIUS messages between the MAG
   and the AAA server.

   Request Accept Reject Challenge #  Attribute

   1       0-1    0      0         1  User-Name
   0-1     0      0      0         4  NAS-IP-Address
   0-1     0-1    0      0         5  NAS-Port
   0-1     0-1    0      0         6  Service-Type
   0-1     0-1    0      0-1      24  State
   0       0-1    0      0        25  Class
   0       0-1    0      0-1      27  Session-Timeout
   0-1     0      0      0        31  Calling-Station-Id
   0-1     0      0      0        32  NAS-Identifier
   0+      0+     0+     0+       33  Proxy-State
   0-1     0      0      0        69  NAS-Port-Type
   0+      0+     0+     0+       79  EAP-Message
   1       1      1      1        80  Message-Authenticator
   0-1     0-1    0      0        89  Chargeable-User-Identity
   0-1     0      0      0        95  NAS-IPv6-Address
   0-1     0-1    0      0       124  MIP6-Feature-Vector
   0       1      0      0       145  Mobile-Node-Identifier
   0-1     0-1    0      0       146  Service-Selection
   0       0-1    0      0       147  PMIP6-Home-LMA-IPv6-Address
   0-1     0-1    0      0       148  PMIP6-Visited-LMA-IPv6-Address
   0       0-1    0      0       149  PMIP6-Home-LMA-IPv4-Address
   0-1     0-1    0      0       150  PMIP6-Visited-LMA-IPv4-Address
   0       0+     0      0       151  PMIP6-Home-HN-Prefix
   0       0+     0      0       152  PMIP6-Visited-HN-Prefix
   0       0-1    0      0       153  PMIP6-Home-Interface-ID
   0       0-1    0      0       154  PMIP6-Visited-Interface-ID
   0       0-1    0      0       155  PMIP6-Home-IPv4-HoA
   0       0-1    0      0       156  PMIP6-Visited-IPv4-HoA
   0       0-1    0      0       157  PMIP6-Home-DHCP4-Server-Address
   0       0-1    0      0       158  PMIP6-Visited-DHCP4-Server-Address
   0       0-1    0      0       159  PMIP6-Home-DHCP6-Server-Address
   0       0-1    0      0       160  PMIP6-Visited-DHCP6-Server-Address
   0       0-1    0      0      TBD1  PMIP6-Home-IPv4-Gateway
   0       0-1    0      0      TBD2  PMIP6-Visited-IPv4-Gateway

6.2.  Table of Attributes

   The following table provides a guide to which attributes may be found
   in authorization process between LMA and the AAA.

   Request Accept Reject Challenge #   Attribute

   1       0-1    0      0         1   User-Name
   0-1     0-1    0      0         4   NAS-IP-Address
   0-1     0-1    0      0         5   NAS-Port
   1       0-1    0      0         6   Service-Type
   0       0-1    0      0        25   Class
   0       0-1    0      0-1      27   Session-Timeout
   0-1     0      0      0        31   Calling-Station-Id
   1       0      0      0        32   NAS-Identifier
   0+      0+     0+     0+       33   Proxy-State
   1       0      0      0        69   NAS-Port-Type
   1       1      1      1        80   Message-Authenticator
   0-1     0-1    0      0        89   Chargeable-User-Identity
   0-1     0-1    0      0        95   NAS-IPv6-Address
   0-1     0-1    0      0       124   MIP6-Feature-Vector
   1       0      0      0       145   Mobile-Node-Identifier
   0-1     0-1    0      0       146   Service-Selection
   0-1     0      0      0       147   PMIP6-Home-LMA-IPv6-Address
   0-1     0      0      0       148   PMIP6-Visited-LMA-IPv6-Address
   0-1     0      0      0       149   PMIP6-Home-LMA-IPv4-Address
   0-1     0      0      0       150   PMIP6-Visited-LMA-IPv4-Address
   0+      0+     0      0       151   PMIP6-Home-HN-Prefix
   0+      0+     0      0       152   PMIP6-Visited-HN-Prefix
   0-1     0-1    0      0       153   PMIP6-Home-Interface-ID
   0-1     0-1    0      0       154   PMIP6-Visited-Interface-ID
   0-1     0-1    0      0       155   PMIP6-Home-IPv4-HoA
   0-1     0-1    0      0       156   PMIP6-Visited-IPv4-HoA
   0-1     0-1    0      0      TBD1   PMIP6-Home-IPv4-Gateway
   0-1     0-1    0      0      TBD2   PMIP6-Visited-IPv4-Gateway

7.3.  Table of Attributes

   The following table provides a list of attributes that may be
   included in the RADIUS Accounting messages.  These attributes are to
   complement the set of accounting attributes already required by
   [RFC2866] and [RFC2869].

   Accounting
   Request       #  Attribute

   0-1         145  Mobile-Node-Identifier
   0-1         146  Service-Selection
   0-1         147  PMIP6-Home-LMA-IPv6-Address
   0-1         148  PMIP6-Visited-LMA-IPv6-Address
   0-1         149  PMIP6-Home-LMA-IPv4-Address
   0-1         150  PMIP6-Visited-LMA-IPv4-Address
   0+          151  PMIP6-Home-HN-Prefix
   0+          152  PMIP6-Visited-HN-Prefix
   0-1         155  PMIP6-Home-IPv4-HoA
   0-1         156  PMIP6-Visited-IPv4-HoA
   0-1          31  Calling-Station-Id
   0-1          80  Message-Authenticator
   0-1          89  Chargeable-User-Identity
   0-1         124  MIP6-Feature-Vector

9.1.  Attribute Type Codes

   This specification defines the following new RADIUS attribute type
   values:

           Mobile-Node-Identifier              145
           Service-Selection                   146
           PMIP6-Home-LMA-IPv6-Address         147
           PMIP6-Visited-LMA-IPv6-Address      148
           PMIP6-Home-LMA-IPv4-Address         149
           PMIP6-Visited-LMA-IPv4-Address      150
           PMIP6-Home-HN-Prefix                151
           PMIP6-Visited-HN-Prefix             152
           PMIP6-Home-Interface-ID             153
           PMIP6-Visited-Interface-ID          154
           PMIP6-Home-IPv4-HoA                 155
           PMIP6-Visited-IPv4-HoA              156
           PMIP6-Home-DHCP4-Server-Address     157
           PMIP6-Visited-DHCP4-Server-Address  158
           PMIP6-Home-DHCP6-Server-Address     159
           PMIP6-Visited-DHCP6-Server-Address  160
           PMIP6-Home-IPv4-Gateway             TBD1
           PMIP6-Visited-IPv4-Gateway          TBD2

Last.. a question to the WG. Currently in the I-D we have a
restriction that PMIP6-Visited-LMA-*-Address can only be added
by the VAAA. Obviously the assumption is that the VAAA belongs
to a different administrative domain than the HAAA. Is there
a need to have this kind of limitation? Meaning, should the
HAAA be allowed for including the PMIP6-Visited-LMA-*-Address
attribute as well? If you think it should, explain why and
which scenario it should apply?

- Jouni (on behalf of the to-be-rfc6572 authors)