RADIUS attribute from rfc2865

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NAS-Port-Type

This Attribute indicates the type of the physical port of the NAS
      which is authenticating the user.  It can be used instead of or in
      addition to the NAS-Port (5) attribute.  It is only used in
      Access-Request packets.  Either NAS-Port (5) or NAS-Port-Type or
      both SHOULD be present in an Access-Request packet, if the NAS
      differentiates among its ports.

   A summary of the NAS-Port-Type Attribute format is shown below.  The
   fields are transmitted from left to right.

    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     |             Value
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
              Value (cont)         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

      61 for NAS-Port-Type.

   Length

      6

   Value

      The Value field is four octets.  "Virtual" refers to a connection
      to the NAS via some transport protocol, instead of through a
      physical port.  For example, if a user telnetted into a NAS toauthenticate himself as an Outbound-User, the Access-Request might
      include NAS-Port-Type = Virtual as a hint to the RADIUS server
      that the user was not on a physical port.

      0       Async
      1       Sync
      2       ISDN Sync
      3       ISDN Async V.120
      4       ISDN Async V.110
      5       Virtual
      6       PIAFS
      7       HDLC Clear Channel
      8       X.25
      9       X.75
      10      G.3 Fax
      11      SDSL - Symmetric DSL
      12      ADSL-CAP - Asymmetric DSL, Carrierless Amplitude Phase
              Modulation
      13      ADSL-DMT - Asymmetric DSL, Discrete Multi-Tone
      14      IDSL - ISDN Digital Subscriber Line
      15      Ethernet
      16      xDSL - Digital Subscriber Line of unknown type
      17      Cable
      18      Wireless - Other
      19      Wireless - IEEE 802.11

      PIAFS is a form of wireless ISDN commonly used in Japan, and
      stands for PHS (Personal Handyphone System) Internet Access Forum
      Standard (PIAFS).

        FreeRADIUS Vendor-Specific dictionary values:

                    0 - Async 
                    1 - Sync 
                    2 - ISDN 
                    3 - ISDN-V120 
                    4 - ISDN-V110 
                    5 - Virtual 
                    6 - PIAFS 
                    7 - HDLC-Clear-Channel 
                    8 - X.25 
                    9 - X.75 
                    10 - G.3-Fax 
                    11 - SDSL 
                    12 - ADSL-CAP 
                    13 - ADSL-DMT 
                    14 - IDSL 
                    15 - Ethernet 
                    16 - xDSL 
                    17 - Cable 
                    18 - Wireless-Other 
                    19 - Wireless-802.11 
                    20 - Token-Ring 
                    21 - FDDI 
                    30 - PPPoA 
                    31 - PPPoEoA 
                    32 - PPPoEoE 
                    33 - PPPoEoVLAN 
                    34 - PPPoEoQinQ 
            

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