RADIUS attribute from rfc8045

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IP-Port-Int-IPv6-Addr

The format of IP-Port-Int-IPv6-Addr TLV is shown in Figure 8.  This
   attribute carries IPFIX Information Element 27, "sourceIPv6Address",
   which is the IPv6 source address before NAT operation (refer to
   ).

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   TLV-Type    |     Length    |        sourceIPv6Address
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                             sourceIPv6Address
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                             sourceIPv6Address
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                             sourceIPv6Address
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           sourceIPv6Address       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                 Figure 8

   TLV-Type

      5

   Length

      Eighteen octets

   sourceIPv6Address

      IPv6 address (128 bits).  This field contains the data
      (ipv6Address) of sourceIPv6Address (27) defined in IPFIX.

   If the internal realm is with an IPv6 address family, the
   IP-Port-Int-IPv6-Addr TLV MUST be included as part of the
   IP-Port-Forwarding-Map Attribute (refer to),
   identified as 241.7.5.

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