RADIUS attribute from rfc6572


When both the MAG and the LMA are in the visited network, the PMIP6-
   Visited-IPv4-HoA attribute (Type value 156) is of type Address and is
   used to exchange information between the VAAA and the MAG on the
   assignment of the IPv4 Home Address to the MN being present in the
   visited network.

   The PMIP6-Visited-IPv4-HoA is also used on the LMA-to-VAAA interface.
   If the LMA delegates the assignment of the IPv4-HoA to the VAAA, the
   attribute MUST contain an address of all zeroes (i.e., in
   the RADIUS Access-Request message.  The Access-Accept message MUST
   have the attribute present if the prior request to the VAAA already
   included one.

   The attribute SHOULD NOT be included if the use of the LMA in the
   home network is authorized (the PMIP6-Home-IPv4-HoA and/or PMIP6-
   Home-LMA-IPv4-Address attributes are already present).  However, if
   the VAAA local policy allows both home and visited LMA addresses to
   be delivered to the MAG, then this attribute MAY also be included.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     |     Reserved      |Prefix-Len |
   |                      Visited IPv4 HoA                         |

      PMIP6-Visited-IPv4-HoA 156.

      = 8 octets

      The 10-bit field reserved for future use.  The value MUST be
      initialized to zero by the sender and MUST be ignored by the

      6-bit unsigned integer indicating the prefix length of the IPv4
      HoA.  If the Visited IPv4 HoA contains an address of all zeroes
      (i.e., ''), then the Prefix-Len MUST be set to 32.

   Visited IPv4 HoA:
      This field is of type Address and contains the IPv4 home address
      of the MN in the visited network.