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Network Working Group                                          D. Garcia
Internet-Draft                                                  R. Marin
Intended status: Experimental                       University of Murcia
Expires: November 3, 2017                                   A. Kandasamy
                                                                A. Pelov
                                                                  Acklio
                                                             May 2, 2017


                    LoRaWAN Authentication in RADIUS
                 draft-garcia-radext-radius-lorawan-03

Abstract

   This document describes a proposal for adding LoRaWAN support in
   RADIUS.  The purpose is to integrate the LoRaWAN network join
   procedure with an Authentication, Authorization and Accounting (AAA)
   infrastructure based on RADIUS.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
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   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on November 3, 2017.

Copyright Notice

   Copyright (c) 2017 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
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   include Simplified BSD License text as described in Section 4.e of



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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
   2.  LoRaWAN support in RADIUS . . . . . . . . . . . . . . . . . .   4
   3.  LoRaWAN Overview  . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Introduction  . . . . . . . . . . . . . . . . . . . . . .   4
     3.2.  LoRaWAN join procedure Key Material . . . . . . . . . . .   4
     3.3.  LoRaWAN joining procedure . . . . . . . . . . . . . . . .   5
     3.4.  LoRaWAN Key Derivation  . . . . . . . . . . . . . . . . .   6
   4.  Integration Overview  . . . . . . . . . . . . . . . . . . . .   7
     4.1.  Mapping LoRaWAN Entities to AAA Infrastructure  . . . . .   7
     4.2.  Assumptions . . . . . . . . . . . . . . . . . . . . . . .   7
     4.3.  Protocol Exchange . . . . . . . . . . . . . . . . . . . .   7
       4.3.1.  Join-Request Attribute  . . . . . . . . . . . . . . .   8
       4.3.2.  Join-Answer Attribute . . . . . . . . . . . . . . . .   9
       4.3.3.  AppSKey Attribute . . . . . . . . . . . . . . . . . .  10
       4.3.4.  NwkSKey Attribute . . . . . . . . . . . . . . . . . .  11
       4.3.5.  Table of Attribute  . . . . . . . . . . . . . . . . .  11
   5.  Open Issues . . . . . . . . . . . . . . . . . . . . . . . . .  12
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   7.  Proof of concept implementation . . . . . . . . . . . . . . .  13
   8.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  14
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  15
     10.2.  Informative References . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Introduction

   Low Power Wide Area Network (LP-WAN) groups several radio
   technologies that allow communications with nodes far from the
   central communication endpoint (base station) in the range of
   kilometers depending on the specifics of the technology and the
   scenario.  They are fairly recent and the protocols to manage those
   infrastructures are in continuous development.  In some cases they
   may not consider aspects such as key management or directly tackle
   scalability issue in terms of authentication and authorization.  The
   nodes to be authenticated and authorized is expected to be
   considerably high in number.  One of the protocols that provide a
   complete solution is LoRaWAN [LoRaWAN].  LoRaWAN is a MAC layer
   protocol that use LoRa as its physical medium to cover long range
   (up-to 20 km depending on the environment) devices.  LoRaWAN is
   designed for large scale networks and currently has a central entity



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   called Network Server which maintains a pre-configured key named
   AppKey for each of the devices on the network.  Furthermore, session
   keys such as NwkSKey and AppSKey used for encryption of data
   messages, are derived with the help of this AppKey.  Since each
   service provider would operate their Network Server individually,
   authenticating the devices becomes a tedious process because of
   inter-interoperability or the roaming challenges between the
   operators.  An illustration of the LoRaWAN architecture can be seen
   in figure Figure 1.  As we know the AAA infrastructure provides a
   flexible, scalable solution.  They offer an opportunity to manage all
   these processes in a centralized manner as happens in other type of
   networks (e.g. cellular, WiFi, etc...) making it an interesting asset
   when integrated into the LoRaWAN architecture.

                     +-------+        +-------+              +--------+
   +------+          |       |        |       |              |        |
   |      +--(LoRa)--+       +--(IP)--+       +-----(IP)-----+        |
   +------+          |       |        |       |              |        |
                     +-------+        +-------+              +--------+
   End-Device         Gateway          Network                  Join
                                        Server                 Server

                      Figure 1: LoRAWAN Architecture

   The End-Device communicates with the Gateway by using the LoRa
   modulation.  The Gateway acts as a simple transceiver, which forwards
   all data do the Network Server, which performs the processing of the
   frames, network frame authentication (MIC verification), and which
   serves as Network Access Port.  This document describes a way to use
   standard RADIUS servers as a Join Server, and to use the RADIUS
   protocol for the interaction between the Network Server and the
   Application Server.  This integration is illustrated in figure
   Figure 2

                  +-------+        +-------+              +--------+
+------+          |       |        |       |              |        |
|AppKey+--(LoRa)--+       +--(IP)--+       +---(RADIUS)---+ AppKey |
+------+          |       |        |       |              |        |
                  +-------+        +-------+              +--------+
End-Device         Gateway          Network                  Join
                                     Server                 Server
                                (+ RADIUS client)      (+ RADIUS server)

    Figure 2: LoRAWAN Architecture with AAA and RADIUS authentication.
   End-Device and RADIUS server have a shared secret - the AppKey, which
         is used to derive the session keys (NwkSKey and AppSKey).





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   The document describes how LoRaWAN join procedure is integrated with
   AAA infrastructure using RADIUS [RFC2865] by defining the new
   attributes needed to support the LoRaWAN exchange.

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

2.  LoRaWAN support in RADIUS

   Regarding the overall functionality, the RADIUS LoRaWAN support
   defines the new Attributes needed for the management of the join
   procedure.  The Network Server will implement a RADIUS client
   supporting this specification and therefore, it MUST implement the
   RADIUS attributes for this service.  The NAS-Port-Type specifying the
   type of port on which the Network Server is authenticating the End-
   Device in this case MAY be 18 ( Wireless - Other ) or a new one
   specifically assigned for LoRaWAN (TBD.).

3.  LoRaWAN Overview

3.1.  Introduction

   The LoRAWAN specification defines how the MAC and PHY layer will be
   used with the LoRa radio technologies.  It defines a process by which
   the smart objects can securely join the network in an authenticated
   way and exchange application information ciphered and integrity
   protected.  The focus of this document is to extend how the process
   of joining is performed by the specification including a AAA
   infrastructure (RADIUS) to accomplish this.  Next we review how the
   keys, and each message is used in the joining procedure.  Then we
   elaborate some assumptions to design the integration of AAA in the
   joining procedure possible.

3.2.  LoRaWAN join procedure Key Material

   The LoRaWAN specification describes 3 keys involved in the joining
   procedure.  One as a root key that will be used to generate the other
   two, which will be used to secure the message exchanges after the
   joining procedure success.  The AppKey key used to derive the other
   two keys, NwkSKey and AppSKey:

   o  The AppKey is an AES-128 application specific key assigned by the
      owner of the application.  This key is derived from an
      application-specific root key that is only known to the




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      application owner and is stored in each device and in the Join
      Server that will perform the authentication.

   o  The NwkSKey is a network session key that is specific to each End-
      Device.  It is shared between the Network Server and the End-
      Device and used to calculate and verify the Message Integrity Code
      (MIC) for each data message, between both entities.  Furthermore,
      it is used to cipher and decipher the payload of MAC-only data
      message.

   o  The AppSKey is an application session key specific to each End-
      Device.  It is in charge of ciphering and deciphering the payload
      of application-specific data messages and is also used to
      calculate and verify the MIC that may be added to the payload of
      application-specific data messages.

3.3.  LoRaWAN joining procedure

   The LoRaWAN joining procedure, as described in the LoRaWAN
   Specification 1.0 [LoRaWAN], consists on one exchange.  The first
   message of this exchange is called join-request (JR) message and is
   sent from the End-Device to the Network Server containing the AppEUI
   and DevEUI of the End-Device with a nonce of 2 octets called
   DevNonce.  Figure 3 summarizes the format.

                 +-------------+-------------+-------------+
   Size (bytes)  |      8      |      8      |      2      |
   +---------------------------+-------------+-------------+
   Join Request  |   AppEUI    |    DevEUI   |   DevNonce  |
                 +-------------+-------------+-------------+

                      Figure 3: Join Request Message

   In response to the join-request, the other endpoint will answer with
   the join-accept (JA) (Figure 4) if the End-Device is successfully
   authenticated and authorized to join the network.  The join-accept
   contains a nonce (AppNonce), a network identifier (NetID), an End-
   Device address (DevAddr), a delay between the TX and RX (RxDelay)
   and, optionally, the CFList (see LoRaWAN specification [LoRaWAN]
   section 7).

               +--------+-----+-------+----------+-------+-------------+
   Size (bytes)|   3    |  3  |   4   |    1     |   1   |16 (Optional)|
   +-------------------------------------------------------------------+
   Join Accept |AppNonce|NetID|DevAddr|DLSettings|RxDelay|    CFList   |
               +--------+-----+-------+----------+-------+-------------+

                       Figure 4: Join Accept Message



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   Next, we enumerate and describe each field involved in the join
   procedure message exchange.

   o  AppEUI: Global application ID in IEEE EUI64 to uniquely identify
      the application provider.

   o  DevEUI: Global End-Device ID in IEEE EUI64 to uniquely identify
      the End-Device

   o  DevNonce: A random value.

   o  AppNonce: A random value or some kind of unique ID provided by the
      Network Server.  This value can be also generated by the AAA
      server, in case the network server wants to rely on the AAA server
      pseudo random number generation.  For this, the AppNonce would be
      empty (set to zero), signaling the AAA server it has to generate
      the AppNonce.

   o  NetID: A network identifier

   o  DevAddr: A 32 bit identifier of the End-Device in the current
      network.  It is composed of the Network ID and the Network
      Address.

   o  DLSettings: 8 bits containing the down-link configuration.

   o  RxDelay: 8 bits containing the delay between TX and RX.

   o  CFList (Optional): Channel frequency list.

3.4.  LoRaWAN Key Derivation

   The keys NwkSKey and AppSKey are derived from the AppKey in both the
   Join Server and the End-Device according to the LoRaWAN specification
   [LoRaWAN] as follows:

   Derivation of the NwkSkey:

   NwkSKey = aes128_encrypt(AppKey, 0x01 | AppNonce | NetID | DevNonce |
   pad16)

   Derivation of the AppSkey:

   AppSKey = aes128_encrypt(AppKey, 0x02 | AppNonce | NetID | DevNonce |
   pad16)

   Note: The pad16 function appends octets of containing "zero" so that
   the length of the data is a multiple of 16.



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4.  Integration Overview

4.1.  Mapping LoRaWAN Entities to AAA Infrastructure

   In the current specification of LoRaWAN [LoRaWAN], there is no
   explicit reference to an external entity to which the Network Server
   can go to authenticate the End-Device.  However, ongoing work related
   to LoRaWAN, such as the work in the LoRa Alliance
   [LoRaAllianceSecurity] sketches the use of a new entity, the Join
   Server, that will be in charge of performing the authentication.
   This separation of responsibilities is also the aim of our work,
   where the Join Server acts as an external AAA server in a AAA
   infrastructure using RADIUS as the protocol to communicate the
   Network Server and the Join Server.  Further, it is under
   consideration the distribution of the AppSKey to a target application
   server instead of the Network Server.  Therefore, the Join Server
   would need another protocol to deliver the AppSKey.  Another RADIUS
   interface could be used for this purpose, though this I-D focuses on
   the joining procedure so far.

4.2.  Assumptions

   For the integration of LoRaWAN joining procedure with RADIUS next we
   describe some assumptions regarding the LoRaWAN specification.  The
   first is that the AppKey is only shared between the AAA server (Join
   Server) and the End-Device.  The outcome of the successful join
   procedure (i.e.  NwkSKey and AppSKey) are sent from the AAA server to
   the network-server.  This allows for the End-Device to exchange
   message with the network-server, once the join procedure is finished,
   as specified in LoRaWAN [LoRaWAN].

4.3.  Protocol Exchange

   The join procedure between the End-Device and the network-server
   entails one exchange consisting on a join-request message and a join-
   response message.  In RADIUS the network-server implements a RADIUS
   client to communicate with the Join Server, which act as AAA Server.

   The protocol exchange is done in the following steps:

   1.  The End-Device sends the join-request message to to the Network
       Server.

   2.  Upon reception of the LoRaWAN join-request message, the Network
       Server creates a RADIUS Access-Request message, with the Join-
       Request attribute containing the original message from the End-
       Device, and the Join-Answer Attribute with all the fields of a
       join-answer message except for the MIC, which will be calculated



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       by the AAA Server (Join Server), since is the one that holds the
       AppKey.

   3.  Once the AAA Server authenticates and authorizes the End-Device,
       sends back the Join-Answer with the MIC generated as specified by
       the LoRaWAN specification.  Furthermore, as a consequence of a
       successful join procedure, the AppSKey (optional) and NwkSKey are
       generated and sent along in AppSKey and NwkSKey Attributes
       respectively.

   4.  The Network Server receives the Access-Accept (if successful),
       obtains the content of the Join-Request attribute and sends it to
       the End-Device, storing in association with that End-Device the
       NwkSKey and the AppSKey.


                                                                AAA
 End-Device              Network Server                Server (Join Server)
-----------                ---------                           -------
    |                         |                                    |
1)  |  JR[MIC]                |                   Access-Request   |
    |------------------------>|                  Join-Request Att  |
    |                         |                  Join-Answer Att*  |
2)  |                         |----------------------------------->|
    |                         |                                    |
    |   gen                   |                                    |  gen
    |    |                    |                                    |   |
    |    |                    |                     Access-Accept  |   |
    |    v                    |                   Join-Answer Att  |   v
    | AppSKey                 |                       AppSKey Att* | AppSKey
3)  | NwkSKey                 |                       NwkSKey Att  | NwkSKey
    |                         |<-----------------------------------|
    |  JA[MIC]                |                                    |
4)  |<------------------------|                                    |
    |                         |                                    |

                            Figure 5: Protocol

4.3.1.  Join-Request Attribute

   Description

   This Attribute contains the original Join-Request message.  This
   attribute will only appear in the Access-Request message.  A summary
   of the Join-Request attribute format is shown below.  The fields are
   transmitted from left to right.





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   0                   1                   2
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |    Length     |     String...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

   TBD. for Join-Request

   Length

   18

   String


   The String field contains an octet string with the Join-Request
   message as received over the network, such as defined in [LoRaWAN].

4.3.2.  Join-Answer Attribute

   Description

   This Attribute is used in both RADIUS Access-Request and RADIUS
   Access-Accept messages.  In the first case, it contains the Join
   Answer message with all the needed values filled by the network-
   server except the MIC (this fact is marked with an *).  With these
   values, the Join Server (AAA server) that holds the AppKey is able to
   create the MIC and compose the final Join Answer message.  In the
   second case, it contains the Join Answer with the MIC generated by
   the Join Server (AAA server).  A summary of the Join-Answer attribute
   format is shown below.  The fields are transmitted from left to
   right.

















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   0                   1                   2
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |    Length     |     String...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

   TBD. for Join-Answer

   Length

   28

   String


   The String field contains an octet string with the Join-Answer as
   received over the network , as defined in [LoRaWAN].

4.3.3.  AppSKey Attribute

   Description

   This Attribute contains the AppSKey, an application session key
   specific for the End-Device.  This attribute is optional, and will
   only appear in the RADIUS Access-Accept message.  A summary of the
   AppSKey attribute format is shown below.  The fields are transmitted
   from left to right.

   0                   1                   2
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |    Length     |     String...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

   TBD. for AppSKey

   Length

   16+

   String






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   The String field contains an octet string containing the Application
   Session Key, as defined in [LoRaWAN].

4.3.4.  NwkSKey Attribute

   Description

   This Attribute contains the NwkSKey, an network session key specific
   for the End-Device.  This attribute will only appear in the Access-
   Accept message.  A summary of the NwkSKey attribute format is shown
   below.  The fields are transmitted from left to right.

   0                   1                   2
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |    Length     |     String...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

   TBD. for NwkSKey

   Length

   16+

   String


   The String field contains the octet string of the Network Session Key
   , as defined in [LoRaWAN].

4.3.5.  Table of Attribute


   Request  Accept  Reject  Challenge   #    Attribute
     1       0       0        0       TBD.   Join-Request
     1       1       0        0       TBD.   Join-Answer
     0       0-1     0        0       TBD.   AppSKey
     0       1       0        0       TBD.   NwkSKey
   Request  Accept  Reject  Challenge   #    Attribute

                        Figure 6: Attributes Table








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5.  Open Issues

   With the purpose of extending the authentication process via AAA
   infrastructures, and concretely, RADIUS, we have faced a question
   regarding the relationship between the AppEUI associated to the
   organization operating the Join Server and the realm used by RADIUS
   to route the AAA information to the AAA Server (Join Server) of that
   organization.

   In particular, the Network Server knows the AppEUI included in the
   Join Request, but it needs to discover the realm (Fully Qualified
   Domain Name) that corresponds to that organizations ID to be able to
   communicate with the concrete RADIUS server.

   NOTE: One option MAY be to use the DNS system to provide the FQDN
   associated to an AppEUI (which is an EUI64 address).  The mapping
   using DNS to find out the domain name associated to an EUI64 address
   has been described in [RFC7043].  However, we would need the inverse
   process.  Nevertheless, this needs further discussion.

6.  Security Considerations

   In the LoRaWAN 1.0 specification, the AppSKey and NwkSKey are not
   sent over the network, they are derived in each of the endpoints that
   communicate, namely the End-Device and the Network Server.  In this
   document we propose relegating the responsibility of deriving the
   Network Session Key and Application Session Key to the RADIUS server
   (the Join Server).  These session keys need to be sent to the Network
   Server and if necessary to the application server.

   To send the messages over the network between the RADIUS server and
   the RADIUS client (in this case the Network Server).  How to provide
   confidentiality to the key distributed is outside the scope of this
   document, nevertheless RadSec (RFC6614) or extensions such as those
   defined in RFC 6218 may be considered to protect the distribution.

   The AAA framework and its key management features become increasingly
   important as the use case of LoRaWAN adds functionality and
   complexity.  This is the case for having the Application Server and
   Network Server as separate entities and each receive its keys.
   Although the utility is apparent in that specific case, it has to be
   considered in any other future use-case that may require key
   management and key distribution.  Another point in favor of using AAA
   can be also appreciated since the modifications required by this
   proposal does not imply the modification of the protocols of the
   constrained link, but the unrestricted network that is used to manage
   LP-WAN.




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7.  Proof of concept implementation

   The proof of concept is implemented using the Go programming
   language, that is well suited for the development of web servers or a
   network servers as in this case.

   The implementation of the network server is from [LoRaSERVER] which
   is tailored with the features of a RADIUS Client and the RADIUS
   server implementation from [RADIUSGo] that is modified to handle
   LoRaWAN attributes.

   The LoRa end-device, pre-configured with AppKey, from Nemeus [MK002]
   is a USB key that can be controlled by UART (AT command) through USB
   interface.  A JAVA application installed on a Linux machine is used
   to send control and data messages from the End-Device.

   The LoRa Gateway is from EXPEMB [EXPEMB] which uses the packet
   forwarder to forward the LoRa packets to the LoRa Network Server.
   The Network Server is run in a docker container on a Linux machine
   transfers the LoRa packets into the RADIUS attributes to be sent to
   the RADIUS server.  For now, the packets are sent to the default
   RADIUS server but in the future this would be changed as per the
   discussion in Section 5 in order to redirect the RADIUS request to
   appropriate RADIUS server.

   The RADIUS server is run in a docker container on a Linux machine
   which contains the mapping between the DevEUI of the End-Device and
   the AppKey.  This AppKey from the map along with the received LoRa
   attributes is used to derive the session keys, NwkSKey and AppSKey,
   in the RADIUS server.  These keys are transported as RADIUS
   attributes back to the network server.


+----------+         +---------+          +-------------+        +---------+
|          |         |  LoRa   |          | Nwk server/ |        | Radius  |
|End-device+---------+ Gateway +----------+   RADIUS    +--------+ Server  |
|          |  LoRa   |         |    IP    |   client    |   IP   |         |
+----------+         +---------+          +-------------+        +---------+


   A successful authentication would result in the session keys, NwkSKey
   and AppSKey, being visible on the network server that can be viewed
   using a web interface and the DevAddr being acquired by the End-
   Device from the Join Accept Lora message.  Running Wireshark on the
   interface between RADIUS server and the Network Server shows the
   RADIUS packets with the LoRa attributes.





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   To simplify the design and implementation, we opted for creating one
   RADIUS Attribute per message, instead of per each field within the
   message since only the authenticating module responsible for the Join
   Procedure in the current network server is delegated to the AAA
   server and the AAA server would be able to obtain the required fields
   from this single attribute, i.e either JoinRequest or JoinAccept
   message.  This design choice would follow the RADIUS guidelines given
   in [RFC6158] identifying it as string for being an opaque
   encapsulation of data structures defined outside RADIUS.  Creating an
   attribute per field, would be useful in case the AAA infrastructure
   would change its behavior depending on the specific content of one or
   more of the fields contained in the message.  This could be the case
   when the LoRaWAN use case becomes more complex and add more
   functionality.

   As future work, we intend to implement the proof of concept in
   FreeRADIUS

8.  Acknowledgments

   This work has been possible partially by the SMARTIE project
   (FP7-SMARTIE-609062 EU Project) and the Spanish National Project
   CICYT EDISON (TIN2014-52099-R) granted by the Ministry of Economy and
   Competitiveness of Spain (including ERDF support).

   We also wanted to thank for the comments received about this document
   by Sri Gundavelli, Yeoh Chun-Yeow, Alan DeKok, Stephen Farrell and
   Mark Grayson.

9.  IANA Considerations

   In this document we define 4 new RADIUS Attributes that would need
   actions from IANA to assign the corresponding numbers.

   +--------+--------------+----------------------------+
   | Number |     Name     |          Reference         |
   +----------------------------------------------------+
   |   TBD  | Join-Request | Section 4 of this document |
   |   TBD  | Join-Answer  | Section 4 of this document |
   |   TBD  | AppSKey      | Section 4 of this document |
   |   TBD  | NwkSKey      | Section 4 of this document |
   +--------+--------------+----------------------------+

10.  References







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10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC2865]  Rigney, C., Willens, S., Rubens, A., and W. Simpson,
              "Remote Authentication Dial In User Service (RADIUS)",
              RFC 2865, DOI 10.17487/RFC2865, June 2000,
              <http://www.rfc-editor.org/info/rfc2865>.

   [RFC6158]  DeKok, A., Ed. and G. Weber, "RADIUS Design Guidelines",
              BCP 158, RFC 6158, DOI 10.17487/RFC6158, March 2011,
              <http://www.rfc-editor.org/info/rfc6158>.

   [RFC7043]  Abley, J., "Resource Records for EUI-48 and EUI-64
              Addresses in the DNS", RFC 7043, DOI 10.17487/RFC7043,
              October 2013, <http://www.rfc-editor.org/info/rfc7043>.

10.2.  Informative References

   [EXPEMB]   EXPEMB, E., "LoRa MultiConnectivity Service Gateway - Last
              Accessed:", July 2016, <www.expemb.com/en/product/
              multi%E2%80%90connectivity-service-gateway-
              sgwmc%E2%80%90x86lr%E2%80%9012132/>.

   [LoRaAllianceSecurity]
              Girard, P., "LoRaWAN - SECURITY a comprehensive insight -
              Online Resource: Last Accessed", July 2016,
              <http://portal.lora-
              alliance.org/DesktopModules/Inventures_Document/
              FileDownload.aspx?ContentID=1085>.

   [LoRaSERVER]
              Acklio, A., "LoRa Server", July 2016,
              <http://www.ackl.io>.

   [LoRaWAN]  Sornin, N., Luis, M., Eirich, T., and T. Kramp, "LoRa
              Specification V1.0", January 2015, <https://www.lora-
              alliance.org/portals/0/specs/
              LoRaWAN%20Specification%201R0.pdf>.

   [MK002]    Nemesus, N., "MK002-xx-EU - Last Accessed:", July 2016,
              <http://www.nemeus.fr/en/mk002-usb-key>.






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   [RADIUSGo]
              bronze1man, B., "Radius: A golang radius library - Last
              Accessed:", July 2016, <https://github.com/bronze1man/
              radius>.

Authors' Addresses

   Dan Garcia-Carrillo (Ed.)
   University of Murcia
   Campus de Espinardo S/N, Faculty of Computer Science
   Murcia  30100
   Spain

   Phone: +34 868 88 78 82
   Email: dan.garcia@um.es


   Rafa Marin-Lopez
   University of Murcia
   Campus de Espinardo S/N, Faculty of Computer Science
   Murcia  30100
   Spain

   Phone: +34 868 88 85 01
   Email: rafa@um.es


   Arunprabhu Kandasamy
   Acklio
   2bis rue de la Chataigneraie
   35510 Cesson-Sevigne Cedex
   France

   Email: arun@ackl.io


   Alexander Pelov
   Acklio
   2bis rue de la Chataigneraie
   35510 Cesson-Sevigne Cedex
   France

   Email: a@ackl.io








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