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Versions: 00 01

i2rs                                                        M. Wang, Ed.
Internet-Draft                                                   J. Chen
Intended status: Informational                                    Huawei
Expires: September 14, 2017                                        R. Gu
                                                            China Mobile
                                                          March 13, 2017


    Information Model of Control-Plane and User-Plane separation BNG
              draft-wcg-i2rs-cu-separation-infor-model-00

Abstract

   To improve network resource utilization and reduce the operation
   expense, the Control-Plane and User-Plane separation conception is
   raised [draft-gu-nfvrg-cloud-bng-architecture-00].  This document
   describes the information model for the interface between Control-
   Plane and User-Plane separation BNG.  This information model may
   involve both control channel interface and configuration channel
   interface.  The interface for control channel allows the Control-
   Plane to send the user's information table to the User-Plane, and the
   User-Plane to report the statistics information to the Control-Plane,
   etc.  The interface for configuration channel is in charge of the
   version negotiation between the CP and UP, the configuration for the
   devices of CP and UP, and the report of UP's capabilities, etc.  The
   information model defined in this document enable defining a
   standardized data model.  Such a data model can be used to define an
   interface to the CU separation BNG.

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
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   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 September 14, 2017.






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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
   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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Concept and Terminology . . . . . . . . . . . . . . . . . . .   4
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Generic Control Plane and User Plane separation BNG Overview    4
   4.  Information Model . . . . . . . . . . . . . . . . . . . . . .   4
     4.1.  Information Model for Control-Plane . . . . . . . . . . .   5
       4.1.1.  User-Related Information  . . . . . . . . . . . . . .   6
         4.1.1.1.  User Information Model  . . . . . . . . . . . . .   6
         4.1.1.2.  IPv4 Information Model  . . . . . . . . . . . . .   7
         4.1.1.3.  IPv6 Information Model  . . . . . . . . . . . . .   7
         4.1.1.4.  QoS Information Model . . . . . . . . . . . . . .   8
       4.1.2.  Port Related Information  . . . . . . . . . . . . . .   9
         4.1.2.1.  Port Information Model  . . . . . . . . . . . . .   9
       4.1.3.  Device Related Information  . . . . . . . . . . . . .  10
         4.1.3.1.  Address field distribute Table  . . . . . . . . .  10
     4.2.  Information Model for User Plane  . . . . . . . . . . . .  11
       4.2.1.  User Related Information  . . . . . . . . . . . . . .  11
         4.2.1.1.  User Information Model  . . . . . . . . . . . . .  11
         4.2.1.2.  IPv4 Information Model  . . . . . . . . . . . . .  12
         4.2.1.3.  IPv6 Information Model  . . . . . . . . . . . . .  13
         4.2.1.4.  QoS Information Model . . . . . . . . . . . . . .  14
         4.2.1.5.  Traffic Statistics Infor  . . . . . . . . . . . .  15
       4.2.2.  Port Related Information  . . . . . . . . . . . . . .  16
         4.2.2.1.  Port Information Model  . . . . . . . . . . . . .  16
         4.2.2.2.  Port Resources of UP  . . . . . . . . . . . . . .  17
       4.2.3.  Device Related Information  . . . . . . . . . . . . .  18
         4.2.3.1.  Address field distribute Table  . . . . . . . . .  18
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  19
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  19
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .  19
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  19



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1.  Introduction

   The rapid development of new services, such as 4K, IoT, etc, and
   increasing number of home broadband service users present some new
   challenges for BNGs such as:

      Low resource utilization: The traditional BNG acts as both a
      gateway for user access authentication and accounting and an IP
      network's Layer 3 edge.  The mutually affecting nature of the
      tightly coupled control and forwarding planes makes it difficult
      to achieve the maximum performance of either plane.

      Complex management and maintenance: Due to the large number of
      traditional BNGs, a network must have each device configured one
      at a time when deploying global service policies.  As the network
      expands and new services are introduced, this deployment mode will
      cease to be feasible as it is unable to manage services
      effectively and rectify faults rapidly.

      Slow service provisioning: The coupling of control planes and data
      planes, in addition to a distributed network control mechanism,
      means that any new technology has to rely heavily on the existing
      network devices.

   To address these challenges, cloud-based BNG with C/U separated
   conception is raised [draft-gu-nfvrg-cloud-bng-architecture-00].  The
   main idea of Control-Plane and User-Plane separation method is to
   extract and centralize the user management functions of multiple BNG
   devices, forming an unified and centralized control plane (CP).  And
   the traditional router's Control Plane and forwarding plane are both
   preserved on BNG devices in the form of a user plane (UP).

   This document describes the information model for the interface
   between Control-Plane and User-Plane separation BNG.  This
   information model may involve both control channel interface and
   configuration channel interface.  The interface for control channel
   allows the Control-Plane to send the user's information table to the
   User-Plane, and the User-Plane to report the statistics information
   to the Control-Plane, etc.  The interface for configuration channel
   is in charge of the version negotiation between the CP and UP, the
   configuration for the devices of CP and UP, and the report of UP's
   capabilities, etc.  The information model defined in this document
   enable defining a standardized data model.  Such a data model can be
   used to define an interface to the CU separation BNG.







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2.  Concept and 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 [RFC2119].

2.1.  Terminology

   BNG: Broadband Network Gateway.  A broadband remote access server
   (BRAS, B-RAS or BBRAS) routes traffic to and from broadband remote
   access devices such as digital subscriber line access multiplexers
   (DSLAM) on an Internet service provider's (ISP) network.  BRAS can
   also be referred to as a Broadband Network Gateway (BNG).

   CP: Control Plane.  The CP is a user control management component
   which support to manage UP's resources such as the user entry and
   forwarding policy

   UP: User Plane.  UP is a network edge and user policy implementation
   component.

3.  Generic Control Plane and User Plane separation BNG Overview

   Briefly, a C/U separated BNG is made up of a CP and a UP.  The CP is
   a user control management component which support to manage UP's
   resources such as the user entry and forwarding policy, for example,
   the access bandwidth and priority management.  And the UP is a
   network edge and user policy implementation component.  It can
   support the forwarding plane functions on traditional BNG devices,
   such as traffic forwarding, QoS, and traffic statistics collection,
   and it can also support the control plane functions on traditional
   BNG devices, such as routing, multicast, etc.

   In CP's view, the UP provides the control management network
   resources such as user's formation, access bandwidth, etc.  The CP
   manages these resources and according to specific service's
   requirements to generate several tables which contains a set of
   rules.  And then CP sends these tables to UP.

   In UP's view, the CP generates tables and provides the rules.  The UP
   receives these tables, parses it, matches these rules, and then
   performs corresponding actions.

4.  Information Model

   This section describes information model that represents the concept
   of the interface of CU separation BNG which is language and protocol
   neutral.



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   The following figure describes the Overview of Information Model for
   CU separation BNG.

                +---CP: (generate Tables, which including several rules)
                |     |
                |     +---PORT information: rule 1, 2, 3 ...
                |     |
                |     +---User Infor: rule 1, 2, 3 ...
                |     |
                |     +---IPv4 Infor: rule 1, 2, 3 ...
                |     |
                |     +---IPv6 Infor: rule 1, 2, 3 ...
                |     |
                |     +---QoS: rule 1, 2, 3 ...
                |     |
                |     +---Address field distribute: rule 1, 2, 3 ...
                |
                +---UP
                     |
                     +---Case 1:(report resources and statistical information)
                     |   |
                     |   +---PORT RESOURCES of UP
                     |   |
                     |   +---Traffic statistics
                     |
                     +---Case 2:(match rules then perform corresponding actions)
                         |
                         +---PORT information: match rules than action
                         |
                         +---User Infor: match rules than action
                         |
                         +---IPv4 Infor: match rules than action
                         |
                         +---IPv6 Infor: match rules than action
                         |
                         +---QoS: match rules than action
                         |
                         +---Address field distribute: match rules than action


4.1.  Information Model for Control-Plane

   This section describes information model for the interface of
   Control-Plane (CP).  As mentioned in section 3, the CP is a user
   control management component which support to manage UP's resources
   and forwarding policy, and base on these resources and specific
   requirements of user's service, generate several tables which
   contains a set of matching rules.



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4.1.1.  User-Related Information

4.1.1.1.  User Information Model

   The User information may contains a set of User's information.  Base
   on above information CP generates corresponding table and matching
   rules.  And then sends it to UP.

   The Figure below illustrates the User Information Table of Control-
   Plane:

        +---CP: (generate Tables, which contains several rules)
            |
            +---User-Infor
                |
                +---SubId
                |
                +---SubMac
                |
                +---AccessType
                |
                +---SessionID
                |
                +---InnerVlanId
                |
                +---OuterVlanId
                |
                +---SubIf

   User Information may include:

      SubID: Identifier of user.

      SubMac: MAC address of user.

      AccessType: Indicate the access type, for example PPPoE, IPoE,
      etc.

      SessionID: The Session Identifier, for example PPPoE session ID.

      InnerVlanID: Identifier of inner VLAN.

      OuterVlanID: Identifier of outer VLAN.

      SubIF: Index of user's interface.






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4.1.1.2.  IPv4 Information Model

   The User-IPv4 information may contains a set of User's information
   and corresponding IPv4 address information.  Base on above
   information CP generates corresponding table and matching rules.  And
   then sends it to UP.

   The Figure below illustrates the IPv4 Information Table of Control-
   Plane:

        +---CP: (generate Tables, which contains several rules)
            |
            +---IPv4-Infor
                |
                +---UserID
                |
                +---SubIPv4
                |
                +---MaskLen
                |
                +---GateWay
                |
                +---VRF



   IPv4-Infor includes:

      UserID: Identifier of User.

      SubIPv4: IPv4 address of user.

      MaskLen: Mask Length.

      GateWay: Gate Way information of user.

      VRF: Identifier of VRF.

4.1.1.3.  IPv6 Information Model

   The User-IPv6 information may contains a set of User's information
   and corresponding IPv6 address information.  Base on above
   information CP generates corresponding table and matching rules.  And
   then sends it to UP.

   The Figure below illustrates the IPv6 Information Table of Control-
   Plane:




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           +---CP: (generate Tables, which contains several rules)
               |
               +---IPv6-Infor
                   |
                   +---UserID
                   |
                   +---SubIPv6
                   |
                   +---IPv6MaskLen
                   |
                   +---PDAddr
                   |
                   +---PDMasklen
                   |
                   +---Vrf


   IPv6 Infor includes:

      UserID: Identifier of User.

      SubIPv6: IPv6 address of user.

      IPv6MaskLen: Mask Length.

      PDAddr: PD address.

      PDMaskLen: PD Mask Length.

      VRF: Identifier of VRF.

4.1.1.4.  QoS Information Model

   In CU separation BNG information model, the Control-Plane (CP)
   generates the QoS Table base on managed UP's bandwidth resources and
   specific QoS requirements of user's services.  This table may
   contains a set of QoS matching rules.  The CP sends this table to UP,
   UP receives and parses this table, matches these QoS rules, and then
   performs corresponding actions.

   The Figure below illustrates the QoS Table of Control-Plane:










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        +---CP: (generate Tables, which including several rules)
            |
            +---PORT-infor
                |
                +--- UserId
                |
                +--- QosSubCarCir
                |
                +--- QosSubCarPir
                |
                +--- QosSubCarCbs
                |
                +--- QosSubCarPbs


   UserId: Identifier of user.

   QosSubCarCir: Committed Information Rate.

   QosSubCarPir: Peak information rate.

   QosSubCarCbs:Committed Burst Size.

   QosSubCarPbs:Peak Burst Size.

4.1.2.  Port Related Information

4.1.2.1.  Port Information Model

   The Port is a logical construct that identifies a specific process or
   a type of network service.  In CU separation BNG information model,
   the Control-Plane (CP) generate the Port-Infor table base on the
   port-resources, which are received from the User-Plane (UP), and the
   specific requirements of user's services.  This table contains a set
   of Port's matching rules.  And then the CP sends this Port-Infor to
   UP

   The Figure below illustrates the Port Information Table of Control-
   Plane:












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        +---CP: (generate tables, which contains several rules)
            |
            +---PORT-infor
                |
                +---IfIndex
                |
                +---BasEn



   IfIndex: Index for interface.

   BasEn: Enable the Bas Port.

4.1.3.  Device Related Information

4.1.3.1.  Address field distribute Table

   In CU separation BNG information model, the Control-Plane (CP)
   generates and sends this Address field distribute Information table
   to UP.  The UP receives and parses this table, matches corresponding
   rules presented in Address-field-distribute, and then performs
   actions

   The Figure below illustrates the Address field distribute Table of
   Control-Plane:

   +---UP:(match rules then perform corresponding actions)
       |
       +---PORT-infor
           |
           +---AddressSegment
           |
           +---AddressSegmentMask
           |
           +---AddressSegmentVrf
           |
           +---NextHop
           |
           +---IfIndex
           |
           +---MaskLen


   AddressSegment: The address segment information.

   AddressSegmentMask: The address segment mask information.




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   AddressSegmentVrf: The address segment VRF.

   NextHop: The next hop.

   IfIndex: The index of the outing interface.

   MaskLen: The Mask length.

4.2.  Information Model for User Plane

   This section describes information model for the interface of User-
   Plane (UP).  As mentioned in section 3, the CP is a network edge and
   user policy implementation component.  It supports: Forwarding plane
   functions on traditional BNG devices, including traffic forwarding,
   QoS, and traffic statistics collection Control plane functions on
   traditional BNG devices, including routing, multicast, and MPLS.

   In CU separation BNG information model, the CP generates tables and
   provides the rules.  The UP plays two roles:

   1.  It receives these tables, parses it, and matches these rules,
       then performs corresponding actions.

   2.  It reports the resources and statistical information to CP.

4.2.1.  User Related Information

4.2.1.1.  User Information Model

   The User information may contains a set of User's information.  In CU
   separation BNG information model, the CP generates and sends this
   Information table to UP.  The UP parses this table, matches
   corresponding rules, and then performs next step of actions.

   The Figure below illustrates the User Information Table of User-
   Plane:















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        +---CP: (generate Tables, which contains several rules)
            |
            +---User-Infor
                |
                +---SubId
                |
                +---SubMac
                |
                +---AccessType
                |
                +---SessionID
                |
                +---InnerVlanId
                |
                +---OuterVlanId
                |
                +---SubIf


   User Information may include:

      SubID: Identifier of user.

      SubMac: MAC address of user.

      AccessType: Indicate the access type, for example PPPoE, IPoE,
      etc.

      SessionID: The Session Identifier, for example PPPoE session ID.

      InnerVlanID: Identifier of inner VLAN.

      OuterVlanID: Identifier of outer VLAN.

      SubIF: Index of user's interface.

4.2.1.2.  IPv4 Information Model

   The IPv4 information may contains a set of User's information and
   corresponding IPv4 address information.  In CU separation BNG
   information model, the CP generates and sends this Information table
   to UP.  The UP parses this table, matches corresponding rules, and
   then performs next step of actions.

   The Figure below illustrates the IPv4 Information Table of User-
   Plane:





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        +---CP: (generate Tables, which contains several rules)
            |
            +---IPv4-Infor
                |
                +---UserID
                |
                +---SubIPv4
                |
                +---MaskLen
                |
                +---GateWay
                |
                +---VRF



   IPv4-Infor includes:

      UserID: Identifier of User.

      SubIPv4: IPv4 address of user.

      MaskLen: Mask Length.

      GateWay: Gate Way information of user.

      VRF: Identifier of VRF.

4.2.1.3.  IPv6 Information Model

   The IPv6 information may contains a set of User's information and
   corresponding IPv6 address information.  In CU separation BNG
   information model, the CP generates and sends this Information table
   to UP.  The UP parses this table, matches corresponding rules, and
   then performs next step of actions.

   The Figure below illustrates the IPv6 Information Table of User-
   Plane:













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           +---CP: (generate Tables, which contains several rules)
               |
               +---IPv6-Infor
                   |
                   +---UserID
                   |
                   +---SubIPv6
                   |
                   +---IPv6MaskLen
                   |
                   +---PDAddr
                   |
                   +---PDMasklen
                   |
                   +---Vrf


   IPv6-Infor includes:

      UserID: Identifier of User.

      SubIPv6: IPv6 address of user.

      IPv6MaskLen: Mask Length.

      PDAddr: PD address.

      PDMaskLen: PD Mask Length.

      VRF: Identifier of VRF.

4.2.1.4.  QoS Information Model

   In CU separation BNG information model, the Control-Plane (CP)
   generates the QOS Table base on managed UP's bandwidth resources and
   specific QoS requirements of user's services.  This table may
   contains a set of QoS matching rules.  The CP sends this table to UP,
   UP receives and parses this table, matches corresponding QoS rules
   presented in the table, and then performs corresponding actions.

   The Figure below illustrates the QoS Table of User-Plane:










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        +---CP: (generate Tables, which including several rules)
            |
            +---PORT-infor
                |
                +--- UserId
                |
                +--- QosSubCarCir
                |
                +--- QosSubCarPir
                |
                +--- QosSubCarCbs
                |
                +--- QosSubCarPbs


   UserId: Identifier of user.

   QosSubCarCir: Committed Information Rate.

   QosSubCarPir: Peak information rate.

   QosSubCarCbs:Committed Burst Size.

   QosSubCarPbs:Peak Burst Size.

4.2.1.5.  Traffic Statistics Infor

   Another role of User-Plane is to report the available network
   resources and statistical information.  This section describes the
   information model of UP's traffic statistics report.  The User-Plane
   captures run time traffic statistics, generates the traffic-
   statistics infor table, and then reports it to Control-Plane.

   The Figure below illustrates the Traffic Statistics Infor Table of
   User-Plane:
















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   +---UP:(report Traffic statistics)
       |
       +---UP-Traffic statistics
           |
           +--- UserID
           |
           +--- StatisticsType
           |
           +--- IngressStatisticsPackets
           |
           +--- IngressStatisticsBytes
           |
           +--- EngressStatisticsPackets
           |
           +--- EngressStatisticsBytes

   UserID: The Identifier of User.

   StatisticsType: Traffic types such as IPv4, IPv6.

   IngressStatisticsPackets: Ingress Statistics Packets

   IngressStatisticsBytes: Ingress Statistics Bytes.

   EngressStatisticsPackets: Engress Statistics Packets

   EngressStatisticsBytes: Engress Statistics Bytes.

4.2.2.  Port Related Information

4.2.2.1.  Port Information Model

   The Port is a logical construct that identifies a specific process or
   a type of network service.  In CU separation BNG information model,
   the Control-Plane (CP) generate the Port-Infor table base on the
   port-resources, which are received from the User-Plane (UP), and the
   specific requirements of user's services.  This table contains a set
   of Port's matching rules.  And then the CP sends this Port-Infor to
   UP

   The Figure below illustrates the Port Information Table of User-
   Plane:









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        +---CP: (generate tables, which contains several rules)
            |
            +---PORT-infor
                |
                +---IfIndex
                |
                +---BasEn



   IfIndex: Index for interface.

   BasEn: Enable the Bas Port.

4.2.2.2.  Port Resources of UP

   Another role of User-Plane is to report the available network
   resources and statistical information.  This section describes the
   information model of UP's port resources report.  The User-Plane
   looks up the available ports, reports them to the Control-Plane.  The
   Control-Plane can generate Port-Infor table base on these information
   and specific requirements of user's services.

   The Figure below illustrates the Port Resources Information Table of
   User-Plane:

   +---UP:(report network resources)
       |
       +---UP-PORT-RESOURCES
           |
           +---IfIndex
           |
           +---IfName
           |
           +---IfType
           |
           +---LinkType
           |
           +---MacAddr
           |
           +---IfPhyState
           |
           +---MTU



   IfIndex: The Index of interface.




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   IfName: The name of interface.

   IfType: The interface type.

   LinkType: The link type.

   MacAddr: The Mac address.

   IfPhyState: The physical state of the interface.

   MTU: Maximum Transmission Unit.

4.2.3.  Device Related Information

4.2.3.1.  Address field distribute Table

   In CU separation BNG information model, the Control-Plane (CP)
   generates and sends this Address field distribute Information table
   to UP.  The UP receives and parses this table, matches corresponding
   rules presented in Address-field-distribute, and then performs
   actions

   The Figure below illustrates the Address field distribute Table of
   User-Plane:

   +---UP:(match rules then perform corresponding actions)
       |
       +---PORT-infor
           |
           +---AddressSegment
           |
           +---AddressSegmentMask
           |
           +---AddressSegmentVrf
           |
           +---NextHop
           |
           +---IfIndex
           |
           +---MaskLen


   AddressSegment: The address segment information.

   AddressSegmentMask: The address segment mask information.

   AddressSegmentVrf: The address segment VRF.




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   NextHop: The next hop.

   IfIndex: The index of the outing interface.

   MaskLen: The Mask length.

5.  Security Considerations

   None.

6.  IANA Considerations

   None.

7.  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>.

Authors' Addresses

   Michael Wang (editor)
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: wangzitao@huawei.com


   Jie Chen
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: chenjie@huawei.com


   Rong Gu
   China Mobile
   32 Xuanwumen West Ave, Xicheng District
   Beijing, Beijing  100053
   China

   Email: gurong_cmcc@outlook.com



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