MIF                                                        Hongke Zhang
Internet Draft                                                 Fei Song
Intended status: Informational                                 Boxin Du
Expires: May 18 2018                                              Mi Du
                                                               Mi Zhang
                                            Beijing Jiaotong University
                                                      November 17, 2017



             MIF API extension for combining IEEE 802.2
             draft-zhang-mif-api-extension-802-21-07.txt




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
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   "work in progress."

   This Internet-Draft will expire on May 18, 2018.



Copyright Notice

   Copyright (c) 2016 IETF Trust and the persons identified as the
   document authors. All rights reserved.




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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with
   respect to this document. Code Components extracted from this
   document must include Simplified BSD License text as described in
   Section 4.e of the Trust Legal Provisions and are provided
   without warranty as described in the Simplified BSD License.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with
   respect to this document. Code Components extracted from this
   document must include Simplified BSD License text as described in
   Section 4.e of the Trust Legal Provisions and are provided
   without warranty as described in the Simplified BSD License.



Abstract

   The Application Program Interface (API) of MIF, specified in the
   MIFAPI consideration, must rely on lower layer functionalities when
   handover between homogeneous or heterogeneous networks is necessary.
   To improve the connectivity performance, the existing MIF API needs
   to be extended. IEEE is also aimed at the similar issue from
   different way. A kind of logical entities over the link layer
   protocol for handling the seamless handover has been defined in
   IEEE802.21. This document proposes a mechanism via integrating MIF
   API and IEEE 802.21 to support application service better.

Table of Contents


   1. Introduction ................................................  4
   2. Terminology .................................................  4
   3. The Relationship between IEEE MIHF and MIF API ............... 5


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   4. The Extension of MIF API for Handover: A Case Study........... 9
      4.1. The MN-initiated Handover ............................... 9
         4.1.1. Get Information  ................................... 10
         4.1.2. Information Post  .................................. 10
         4.1.3. Parameter Report  .................................. 10
         4.1.4. Check Resources MN  ................................ 10
         4.1.5. Resource Availability  ............................. 11
         4.1.6. Connect to Interface  .............................. 11
         4.1.7. Resource Preparation Messages  ..................... 11
         4.1.8. Establish Link Messages  ........................... 11
         4.1.9. Link Up ............................................ 11
         4.1.10. Handover Completed ................................ 12
         4.1.11. Handover Completion Confirmation .................. 12
      4.2. The Network-initiated Handover  ......................... 12
         4.2.1. Candidate Query Notification  ...................... 13
         4.2.2. Candidate Query Result  ............................ 13
         4.2.3. Check Resources Net  ............................... 13
         4.2.4. Confirm Chosen Target  ............................. 13
         4.2.5. Establish Link Messages  ........................... 14
         4.2.6. Link Up  ........................................... 14
         4.2.7. Handover Completed  ................................ 14
         4.2.8. Handover Completion Confirmation  .................. 14
   5. Discussions for New Messages from MIF Perspective  ........... 14
      5.1. Get Information  ........................................ 14
      5.2. Release the Ongoing Connection  ......................... 15
      5.3. Establish New L2 Connection  ............................ 15
   6. Discussions for New Messages from IEEE Perspective  .......... 15
   7. Security Considerations  ..................................... 18
   8. IANA Considerations   ........................................ 18
   9. References   ................................................. 19
      9.1. Normative References  ................................... 19
      9.2. Informative References  ................................. 19
   10. Acknowledgments   ........................................... 19










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1. Introduction

   In MIF context, the improvement of connectivity experiences SHOULD
   be produced. Enhancing the performance of horizontal and vertical
   switches between networks is the main target. The aforementioned
   situation is quite similar with Media Independent Handover (MIH)
   described in [IEEE 802.21]. Even though the MIF Application Program
   Interface (API) specified in the MIF API consideration [I-D.ietf-
   mif-api-extension] illustrates a series of message in multiple
   interface scenarios, this draft only provides a minimal set of
   message calls REQUIRED to implement the API. Hence, new functions
   could be added.

   In terms of [IEEE 802.21], the Media Independent Handover Function
   (MIHF) is a logical entity, which can facilitate MIH decision making
   based on inputs from the MIHF. Abstracted services can be provided
   for higher layers by MIHF. Also, it can communicate with the lower
   layer of the mobility-management protocol stack through technology-
   specific interfaces in MIHF.

   As two mechanisms, MIF API and MIHF, are working in different layers
   and defined by different organizations, the requirements of
   compatibility are distinct. Connection manager (i.e. the MIHF)
   SHOULD support some of the functions of MIF API, and vice versa. The
   functions of MIHF could be utilized in MIF API in order to handover
   issues according to the advantages of both MIHF and its Service
   Access Points (SAPs). Message calls of MIF API is extended by this
   document to support the MIH. Similar with [I-D.ietf-mif-api-
   extension], because they are left up to the implementation, there
   are no bindings for programming languages being provided. This
   document only illustrates the messages sending and receiving, which
   can be read as a checklist for operating system vendors.

2. Terminology

   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].





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3. The Relationship between IEEE MIHF and MIF API

   The purpose of IEEE 802.21 is to further the user experience of
   mobile devices through facilitating handover among all IEEE.802
   networks despite of whether they are of different media types or not,
   including both wired and wireless. Also, the target is to make it
   possible for mobile devices to perform seamless handover between
   IEEE 802 and non IEEE networks. This standard defines:

   1. A framework that enables service continuity while a Mobile Node
      (MN) transitions between heterogeneous link-layer technologies.

   2. MIHF.

   3. MIH_SAP and associated primitives for users to get services of
      MIHF.

   4. The definitions of new link-layer SAPs and associated primitives
      for each link-layer technology. They help MIHF to collect link
      information and control link behaviors during handovers.

      MIHF is a functional entity to fulfill the high- performance
      handovers. The fundamental advantage of MIHF is that it provides
      media-specific technology of lower layer is being used, such as
      IEEE Std.802.3, IEEE Std.802.11, IEEE Std.802.16, 3GPP and 3GPP2.
      Besides, three kinds of SAPs (will be detailed later) of MIHF are
      also defined and their primitives that interact between different
      layers.

   The MIHF can also act as a filter: the messages received from link
   layer SHOULD be processed and submitted to higher layer for meeting
   the subscribers' need. Therefore, MIHF should work under MIF API. In
   fact, MIF API SHOULD be served as a user of MIHF, as shown in Figure
   1. The subscribers can then only interact with the MIHF via one kind
   of SAPs (i.e. MIH_SAP) without knowing the lower things. The MIH
   protocol is not in the scope of this document.

   Three kinds of MIHF services are defined in the standard: Media
   Independent Event Service (MIES), Media Independent Command Service
   (MICS) and Media Independent Information Service (MIIS).



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   MIES provides event's degree, for event filtering and event
   reporting corresponding to dynamic changes in link characteristics,
   link status and link quality. It originates from lower layers and
   can be passed to MIHF or upper layers for the detection of handover
   requirement. MTH users manage and control link behavior relevant to
   handover and mobility by MICS. It is invoked by users or MIHF and
   makes effect on MIHF or lower layers.

   For example, in MN-initiated handover scenario, MICS is adopted for
   MN switching between different links. MIIS makes it possible for MN
   and network entities discovering information which has influence on
   the selection of appropriate networks during handovers. Figure 2
   [IEEE 802.21] shows MIH services and their initiation.

   +------------------------------------------------------+
   |                                                      |
   |                    Application                       |
   |                                                      |
   +---+--------+-------+---+------------+-----+----------+
       ^        |       ^   |            ^     |
       |        |       |   |            |     |
       |        v       |   |            |     |
   +---+--------+----+  |   |            |     |
   |                 |  |   |            |     |
   | High Level API  |  |   |            |     |
   |                 |  |   |            |     |
   +---+--------+----+  |   |            |     |
       ^        |       |   |            |     |
       |        |       |   |            |     |
       |        v       |   v            |     |
   +---+--------+-------+---+----+       |     |
   |                             |       |     |
   |         MIF API             |       |     |
   |                             |       |     |
   +---+--------+----------------+       |     |
       |        |                        |     v
       |        |       +----------------+-----+-----------+
       |        |       |                                  |
       |        |       |         Communication API        |


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       |        |       |                                  |
       |        |       +---------+----+-------------------+
       |        |                 ^    ^
       |        |                 |    |
       |        |                 v    v
   +---+--------+-----------------+----+-------------------+
   |                                                       |
   |                         MIHF                          |
   |                                                       |
   +-------------+------------------------+----------------+
                 ^                        |
                 |                        |
   +-------------+------------------------v----------------+
   |                                                       |
   |                  Network Link API                     |
   |                                                       |
   +------+--------+-----------------------+-------+-------+
          ^        |                       ^       |
          |        |                       |       |
          |        |                       |       |
   +------+--------v-----+          +------+-------v-------+
   |                     |          |                      |
   |        Network      |          |       Network        |
   |      Interface 1    |          |     Interface 2      |
   |                     |          |                      |
   +---------------------+          +----------------------+

           The relationship of the MIHF & MIF API
   The letters a, b, c in Figure 2 respectively represent:

 a. MIH_SAP

 b. MIH_LINK_SAP

 c. LLC_SAP

   The SAPs are divided into two categories:

   1) Media dependent SAP (including MIH_LINK_SAP and LLC_SAP).

   2) Media independent SAP (MIH_SAP).


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+--------------+-+  Command       +------------------------------------+
|              |    Service       |                                    |
|              |                  |       MIH User                     |
|           +--+--+  <---------+  |                                    |
|           |     |               |       Layer 3 or Higher            |
| MIHF      |     |  Event        |       Mobility Protocol            |
|           |     |  Service      |                                    |
| Event     |  a  |               |                                    |
| Service   |     | +-----------> |                                    |
|           |     |  Information  |                                    |
| Command   |     |  Service      |   +--------+          +---------+  |
| Service   |     |               +---+     c  +-+-----+--+    c    +--+
|           +--+--+  <----------> |   |        | |     |  |         |  |
| Information  |     Command      |   +--------+ |     |  +---------+  |
| Service      |     Service    +-+--+           |     |               |
|              |                |    |           |     |               |
|              | +----------->  |    |           |     |               |
|              |     Event      |    | Network1  |   +-+--+  Network2  |
|              |     Service    |  b | (e.g.IEEE |   |    |  (e.g.IEEE |
|              |                |    |  802.16)  |   |  b |  802.11)   |
|              |  <----------+  |    |           |   |    |            |
|              |     Information|    |           |   |    |            |
|              |     Service    |    |           |   |    |            |
|              |                +-+--+           |   |    |            |
|              | <------------>   |              |   +---++            |
|              |                  |              |       |             |
|              |                  |              |       |             |
|              |                  +--------------+       +-------------+
+--------------+
                         MIH services and their initiation
   SAP of the MIHF (i.e. MIH_SAP) is media independent. The interface
   between the MIHF and MIH users is defined by the MIH_SAP such as an
   upper layer mobility protocol or a handover function (e.g., MIF API)
   that might reside at higher layer transport entity as well. MIHF is
   allowed by MIH_SAP to provide services to the upper layers, the
   network management plane and the data bearer plane. Upper layers
   need to subscribe with the MIHF as users to receive MIHF events. In
   MIF case, the MIF API can directly send commands to the local MIHF
   via messages which use the service primitives of the MIH_SAP.




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   All the messages REQUIRED for communicating successfully in MIF
   environment that described in the [I-D.ietf-mif-api-extension] MUST
   also be used here. These messages define the way that MIF API
   interacts with the higher layers or applications and need to be
   added into this set for handover process. These new messages SHOULD
   be exchanged between MIHF and MIF API. The service of MIHF is used
   by some of them.



4. The Extension of MIF API for Handover: A Case Study

   This section introduces the extension of message calls of MIF API in
   two parts based on the classification of handovers (MN-initiated
   handover and the network-initiated handover). In order to handle
   these two kinds of handovers successfully, MIF API SHOULD be
   extended respectively based on the characteristics of process.

4.1. The MN-initiated Handover

   The handover initiated by MN includes the following seven steps:

   1)Information query. The MN collects network information from the
   MIIS server which the MN is connected to.

   2)Resource availability check. The MIF API sends request to find
   candidates and then receives a list of candidate networks in
   response message.

   3)Resource preparation. The MN SHOULD determine which target network
   is suitable and request it for resource preparation.

   4)Establish new L2 connection. The MIF API initiates a new link
   connection.

   5)Link up indication. The MIHF of MN notifies the MIF API that the
   link is up.

   6)Higher layer handover execution.




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   7)Resource release. The original serving network resources must be
   released in the end.

   The following messages need to be added, which describe interactions
   between a MIHF and MIF APIs.

4.1.1. Get Information

   This message is sent by the MIF API for the inquiry of the
   neighboring networks information. In MIH, the MIH_Get_Information. is
   use to request for the same purpose. After receiving this message,
   the MIHF inquires the MIIS server for the information, which will
   return a list of network information for MIF API.

4.1.2. Information Post

   This message is sent to the MIF API by the MIIS server as a response
   to the Get Information message. MIH_Get_Information. confirm can be
   used to convey such information.

4.1.3. Parameter Report

   The lower layers link status needs to be sent to the MIF API to
   better control the whole connection when connecting to a specific
   network. Reports can be sent to the MIHF from the link layers and
   then submit to the higher layers. If the link is going down, the MIF
   API must notify its subscribers using "Interface is going away"
   message. The application or higher API SHOULD establish new
   connections by sending "Wants to connect" to MIHF and the connection
   process will restart from step 2 (i.e. Resource availability check).

   Another situation is when the MIF API receives a "Wants to connect"
   message from its subscriber, it SHOULD trigger a whole connection
   process to a new network accordingly. This can also begin from step
   2.

4.1.4. Check Resources MN

   In the connection starts period, the resource availability SHOULD be
   checked by the MN at the candidate networks. This message is sent to
   the MIHF by the MIF API. Then each candidate SHOULD be requested by


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   the serving network. The higher layer can receive the final result.
   The MIH_MN_HO_Candidate_Query. request can be used in the MIH case.

4.1.5. Resource Availability

   When receiving the resource availability of the candidates from the
   serving network, the MIHF SHOULD submits these messages to the MIF
   API. The MIH_MN_HO_Candidate_Query. confirm can be used in the MIH
   case.

4.1.6. Connect to Interface

   This message is sent to the MIF API by the upper applications. When
   the MIF API receives the Resource Availability, it could post the
   message to the higher layer. The upper application use "Connect to
   Interface" to choose a better network interface. More about the
   choosing methods need further discussion.

4.1.7. Resource Preparation Messages

   The MIF API can use the MIH_MN_HO_Commit. request, which includes the
   target network information to request the network chose for resource
   preparation. The MIHF receives the response from the target network
   when the preparation is done. In order to inform the status of the
   previously issued target notification request, it sends a
   MIH_MN_HO_Commit. confirm message to the MIF API.

4.1.8. Establish Link Messages

   The connection establishment problem can be solved by MIF API using
   the MIH_Link_Action. request. This message primitively defined by the
   [IEEE 802.21] is to control the local or remote lower link layers.
   It includes a MIHF ID and a Link Actions List, which can realize
   many controlling functions. The MIF API should receive a
   MIH_Link_Action. confirm to indicate the result, after the action has
   been executed.

4.1.9. Link Up

   After the new link is established, a Link_Up. indication is delivered
   by MAC layers to MIHF. The MIHF then passes the MIH_Link_Up.


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   indication message to the MIF API. The MIF API can notify the upper
   applications using the "Link is going up" message. Then the higher
   layer handover execution might be triggered and the traffic flow can
   be re-established.

4.1.10. Handover Completed

   This message is sent to the MIF API by the MIHF, which indicates
   that the resource of the previous network is successfully released.

4.1.11. Handover Completion Confirmation

   This message is sent to the MIF API by the MIHF indicating that the
   resource of the previous network is successfully released.

4.2. The Network-initiated Handover

   There are also seven steps in an intact network-initiated handover,
   like the MN-initiated handover:

   1)Information query.

   2)Resource availability check.

   3)Resource preparation.

   4)Establish a L2 connection using MIH_Link_Action. request.

   5)Sent link indications to the MIF API.

   6)Higher layer handover execution.

   7)Resource release.

   The differences between Network-initiated case and MN-initiated case
   are in step 1 and step 2. The MIH user of the serving network can
   initiate the Get Information Request and Information Query
   respectively. Such MIH user will send requests to the MN for a
   response message containing the MN's handover acknowledgement for
   MN's preferring link and PoS lists, when it obtains the information
   from the MIIS server.


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   In step 3, the commitment of target network is also initiated by the
   MIH user of a serving network. After the resource is prepared, the
   PoS of serving network SHOULD notify the MN for the establishment of
   L2 connection in step 4.

   The following messages should be added in MIF API.

4.2.1. Candidate Query Notification

   MN's MIHF receives this message from the PoS of the serving network
   with a list of PoAs of each candidate network link. Such message
   suggests the MN SHOULD consider new access network. This message can
   use the MIH_Net_HO_Candidate_Query. Indication.

4.2.2. Candidate Query Result

   This message is sent to the local serving network's MIHF from MN's
   MIF API, specifying whether the request of handover is permitted or
   not. MIH_Net_HO_Candidate_Query. response can be used here. A new
   access network SHOULD be considered at the handover initiation stage,
   when the handover is permitted.

4.2.3. Check Resources Net

   This message is sent to the MN's MIF API by the PoS of serving
   network with a list of target network information and a set of
   resource parameters assigned to the MN for handover.

   MIH_Net_HO_Commit. indication can be used. TThen the establishment of
   L2 can be triggered by the MIF API using Link_Action. request. After
   the link connection is done, MIF API needs inform the serving
   network. Link_Action. request might also have a list of actions for
   handover control during the link connection period.

4.2.4. Confirm Chosen Target

   The MN's MIF API sent this message as a response to the
   MIH_HO_Commit. indication, revealing that the indication is received.
   MIH_Net_HO_Commit. response can be used. Also such message might
   include a list of the results of previous actions.



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4.2.5. Establish Link Messages

   This message is exactly the same as that of the MN-initiated process,
   for establishing a new L2 link connection.

4.2.6. Link Up

   This message is exactly the same as that of the MN-initiated process,
   for informing the MIF API that the L2 link is completed.

4.2.7. Handover Completed

   This message is exactly the same as that of the MN-initiated process,
   for releasing the resources that have already attained by the MN.

4.2.8. Handover Completion Confirmation

   This message is exactly the same as that of the MN-initiated process,
   for confirming that the resources of the previous network are
   successful.

5. Discussions for New Messages from MIF Perspective

   New messages described in this document are critical for information
   exchanging and function achievement between MIHF and MIF API. Since
   both "upper layer requirements gathering" and "lower layer command
   delivering" (or reverse) can be achieved via messages, the logical
   relationship should be discussed in-depth. The messages below are
   only the examples. Further updating is needed.

5.1. Get Information

   According to [IEEE 802 21] this information query is related to a
   specific interface. It has the flexibility to query either a
   specific data within a network interface or an extended schema of a
   given network. As "Announce Interface", "Announce PVD" and "Announce
   IE (Information Elements)" are sent by an advanced application or
   upper APIs, the MIF API could obtain the information via the
   Get_information. request in MIH.




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5.2. Release the Ongoing Connection

   The [I-D.ietf-mif-api-extension] defines a message "Connection can
   be broken", which means that the MN can tolerate the connection
   being broken, e.g. for power conservation. When the subscribers of
   MIF API delivers this message, the MIF API SHOULD send "Release the
   ongoing connection" to the MIHF so that directly releasing the
   current resources of network to cut off this connection, which will
   not weaken the application function.

5.3. Establish New L2 Connection

   According to [IEEE 802.21], a L2 link connection can be triggered by
   the MIH_Link_Actions. The MIF API will receive "Connect to Address"
   or "Connect to Address from Address" messages, when MN wants to
   build a TCP connection with an IP host. Then the MIF API can use the
   MIH_Link_Actions. request to ask MIHF for new L2 link connection.

6. Discussions for New Messages from IEEE Perspective

   The following tables, table1, 2, 3 and 4, are from the [IEEE 802.21].
   These messages might be used in the MIF API because they are
   exchanged between the MIHF and its MIH users. Even though some of
   them have been discussed above, the specific usage of the rest is
   not represented. This section presents only a direct list of their
   category and brief descriptions. Further discussion is needed.

   +---------------------+-------------------------------------------+
   | Messages            | Description                               |
   | (Information)       |                                           |
   +---------------------+-------------------------------------------+
   | MIH_Get_Information | Request to get information from repository|
   +---------------------+-------------------------------------------+
   | MIH_Push_Information| Notify the MN of operator policies or     |
   |                     | other information                         |
   +---------------------+-------------------------------------------+
                  Table 1 Information Messages of MIHF







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   +---------------------+--------------------------------------------+
   | Messages (Event)    |  Description                               |
   +---------------------+--------------------------------------------+
   | MIH_Link_Detected   |  Link of a new access network has been     |
   |                     |  detected. This event is typically on      |
   |                     |  the MN when the first PoA of an access    |
   |                     |  network is detected                       |
   +---------------------+--------------------------------------------+
   | Track_timeout       |  This event is not generated when          |
   |                     |  subsequent PoAs of the same access        |
   |                     |  network are discovered                    |
   +---------------------+--------------------------------------------+
   | MIH_Link_Up         |  L2 connection is established and link     |
   |                     |  is available for use                      |
   +---------------------+--------------------------------------------+
   | MIH_Link_Down       |  L2 connection is broken and link is       |
   |                     |  not available for use                     |
   +---------------------+--------------------------------------------+
   | MIH_Link_Paremeters |  Link parameters have crossed a speci-     |
   | _Report             |  fied threshold and need to be reported    |
   +---------------------+--------------------------------------------+
   | MIH_Link_Going_Down |  Link conditions are degrading and         |
   |                     |  connection loss is imminent               |
   +---------------------+--------------------------------------------+
   | MIH_Link_Handover   |  L2 handover is imminent based on ei-      |
   | _Imminent           |  ther the changes in the link condition    |
   |                     |  or additional information available in    |
   |                     |  the network                               |
   +---------------------+--------------------------------------------+
   | MIH_Link_Handover   |  L2 handover to a new PoA has been         |
   | _Complete           |  completed                                 |
   +---------------------+--------------------------------------------+
   | MIH_Link_PDU        |  Indicate transmission status of a PDU     |
   | _Transmit_Status    |                                            |
   +---------------------+--------------------------------------------+
                Table 2 Event Messages of MIHF



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   +---------------------+--------------------------------------------+
   | Messages (Command)  |  Description                               |
   +---------------------+--------------------------------------------+
   | MIH_Link_Get        |  Get the status of a link                  |
   | _Parameters         |                                            |
   +---------------------+--------------------------------------------+
   | MIH_Net_HO          | Network initiates handover and sends a list|
   | _Candidate _Query   | of suggested networks and associated points|
   |                     | of attachment                              |
   +---------------------+--------------------------------------------+
   | MIH_Link_Configure  | Configure link parameter thresholds        |
   | Thresholds          |                                            |
   +---------------------+--------------------------------------------+
   | MIH_Link_Actions    | Control the behavior of a set of links     |
   +---------------------+--------------------------------------------+
   | MIH_MN_HO_          | Command used by MN to query and obtain     |
   | _Candidate Query    | handover related information about possible|
   |                     | candidate networks                         |
   +---------------------+--------------------------------------------+
   | MIH_N2N_HO_Query    | command sent by the serving MIHF entity to |
   | _Resources          | the target MIHF entity for resource query  |
   +---------------------+--------------------------------------------+
   | MIH_MN_HO_Commit    | Command used by MN to notify the serving   |
   |                     | network of the decided target network      |
   |                     | information                                |
   +---------------------+--------------------------------------------+
   | MIH_Net_HO_Commit   | Command used by the network to notify the  |
   |                     | MN of the decided target network informatio|
   +---------------------+--------------------------------------------+
   | MIH_N2N_HO_Commit   | Command used by a serving network to inform|
   |                     | a target network that an MN is about to    |
   |                     | move toward that network, initiate context |
   |                     | transfer and perform handover preparation  |
   +---------------------+--------------------------------------------+
   | MIH_MN_HO_Complete  | Notification from MIHF of the MN to the    |
   |                     | target or source MIHF indicating the       |
   |                     | status of handover completion              |
   +---------------------+--------------------------------------------+
   | MIH_N2N_HO_         | Notification from MIHF of the MN to the    |
   | Complete            | target or source MIHF indicating the       |
   |                     | status of handover completion              |
   +---------------------+--------------------------------------------+
   | MIH_N2N_HO          | Notification from either source or target  |
   | Complete            | MIHF to the peer MIHF indicating the status|
   |                     | of the handover completion                 |
   +---------------------+--------------------------------------------+
                  Table 3 Command Messages of MIHF


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   +---------------------+-------------------------------------------+
   | Messages            | Description                               |
   |(Service management) |                                           |
   +---------------------+-------------------------------------------+
   | MIH_Capability      | Discover list of Events and Commands      |
   | _Discover           | supported by MIHF                         |
   +---------------------+-------------------------------------------+
   | MIH_Register        | Register with a remote MIHF               |
   +---------------------+-------------------------------------------+
   | MIH_DeRegister      | Deregister with a remote MIHF             |
   +---------------------+-------------------------------------------+
   | MIH_Event_Subscribe | Subscribe for MIH event notification      |
   +---------------------+-------------------------------------------+
   |MIH_Event_Unsubscibe | Unsubscribe from MIH event notification   |
   +---------------------+-------------------------------------------+
                     Table 4 Service Management of MIHF

7. Security Considerations

   This document does not contain any security considerations.

8. IANA Considerations

   There are presently no IANA considerations with this document.








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9. References

9.1. Normative References

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicat
   Requirement Levels", BCP 14, RFC 2119, March 1997.

9.2. Informative References

   [IEEE 802.21] IEEE, "IEEE Standard for Local and Metropolitan Area
   Networks Part 21: Media Independent Handover Services", IEEE LAN/MAN
   Std 802.21-2008, January 2009.

   <http://www.ieee802.org/21/private/Published%20Spec/802.21-2008.pdf>.

   [I-D.ietf-mif-api-extension] Liu, D., Lemon, T., Ismailov, Y., and
   Z.Cao, "MIF API consideration", draft-ietf-mif-api-extension-05
   (work in progress), Feb. 2014.

10. Acknowledgments

   This document was prepared using 2-Word-v2.0.template.dot.




















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   Authors' Addresses

   Hongke Zhang
   Beijing Jiaotong University (BJTU)
   Beijing, 100044, P.R.China

   Email: hkzhang@bjtu.edu.cn


   Fei Song
   Beijing Jiaotong University (BJTU)
   Beijing, 100044, P.R.China

   Email: fsong@bjtu.edu.cn


   Boxin Du
   Beijing Jiaotong University (BJTU)
   Beijing, 100044, P.R.China

   Email: 10291070@bjtu.edu.cn


   Mi Zhang
   Beijing Jiaotong University (BJTU)
   Beijing, 100044, P.R.China

   Email: 13120174@bjtu.edu.cn














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