RADIUS attribute from rfc6572

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PMIP6-Visited-Interface-ID

The PMIP6-Visited-Interface-ID attribute (Type value 154) is of type
   String and contains the MN's interface identifier.  The selection of
   the interface identifier SHOULD NOT allow the tracking of individual
   MNs or users between PMIPv6 mobility session for privacy reasons.This attribute is applicable in network systems and link
   technologies, where the network explicitly delivers an interface
   identifier to the MN during the link setup. 3GPP and PPP link
   technologies are examples of such.

   This attribute MAY be sent by the LMA or the MAG to the VAAA in the
   RADIUS Access-Request packet as a proposal.  This attribute MAY be
   sent by the VAAA to the LMA or to the MAG in an Access-Accept packet;
   however, it MUST be present if the prior request already included
   one.

    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 Interface Identifier
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                       Visited Interface Identifier
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     Visited Interface Identifier  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type:
      PMIP6-Visited-Interface-ID 154.

   Length:
      = 10 octets.

   Visited Interface Identifier:
      The 64-bit long interface identifier (8 octets).

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