The Data Model of Netork Infrastructure Device Management Plane Security Baseline
draft-lin-sacm-nid-mp-security-baseline-00

Versions: 00                                                            
Security Automation and Continuous Monitoring (SACM)              Q. Lin
Internet-Draft                                                    L. Xia
Intended status: Standards Track                                  Huawei
Expires: March 11, 2018                                September 7, 2017


The Data Model of Netork Infrastructure Device Management Plane Security
                                Baseline
               draft-lin-sacm-nid-mp-security-baseline-00

Abstract

   Network infrastructure devices such as routers, switches are
   important parts for network security.  This document describes
   security baseline for network infrastructure device management plane,
   with YANG output, to provide a minimum set of important security
   management features.  The security baselines for control plane, data
   plane, application layer and infrastructure layer of network
   infrastructure devices are described in [I-D. ietf-dong-sacm-nid-cp-
   security-baseline], [I-D.ietf-xia-sacm-nid-dp-security-baseline], [I-
   D.ietf-xia-sacm-nid-app-infr-layers-security-baseline], respectively.

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 https://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 March 11, 2018.

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
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents



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   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  Data Model Structure  . . . . . . . . . . . . . . . . . . . .   4
     5.1.  User Interface Security . . . . . . . . . . . . . . . . .   4
     5.2.  Remote Login Security . . . . . . . . . . . . . . . . . .   5
     5.3.  snmp management security  . . . . . . . . . . . . . . . .   7
     5.4.  AAA . . . . . . . . . . . . . . . . . . . . . . . . . . .   9
     5.5.  Log Security  . . . . . . . . . . . . . . . . . . . . . .  10
     5.6.  File Security . . . . . . . . . . . . . . . . . . . . . .  12
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  12
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   Securing network infrastructure devices is a challenging and critical
   task for organizations and operators to preserve the confidentiality,
   integrity and availability of network and network traffic
   information.  The development and deployment of the security baseline
   for network infrastructure is needed to provide a solid foundation
   for the overall network security.

   To address threats and attacks to network infrastructure devices,
   different security functions are implemented in application layer,
   network layer and infrastructure layer.  Network layer of network
   infrastructure devices is typically categorized into three planes of
   operation, management plane, control plane and data plane.  All the
   planes should be protected and monitored to provide secure network.

   This document focuses on security baseline for network infrastructure
   device management plane.  Management plane provides configuration and
   monitoring services of network infrastructure devices.  It provides a
   platform for all the system management traffic.  Unauthorized access,
   using insecure access channels, implementing insecure cryptographic



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   algorithms are common security issues that break management plane
   security.  To enhance security, secure configuration should be
   implemented to ensure proper configuration and control of network
   infrastructure devices.  A number of security best practices have
   been proposed, such as disabling unused services and ports,
   discarding insecure access channels, enforce strong user
   authentication and authorization, etc.  In this document, we propose
   the most important and universal points of management plane security
   baseline to provide a minimum set.  Thus, future extensibility can be
   achieved.

   YANG subscribed notifications via SACM Statements
   [I-D.ietf-birkholz-sacm-yang-content] defines a method of
   constructing the YANG data model scheme for the security posture
   assessment of the network infrastructure device by brokering of YANG
   push telemetry via SACM statements.  In this document, we follow the
   same way to define the YANG output for network infrastructure device
   security posture based on the SACM Information Model
   [I-D.ietf-sacm-information-model].

   Besides management plane security baseline, the security baselines
   for control plane, data plane, application layer and infrastructure
   layer of network infrastructure devices are described in [I-D.ietf-
   dong-sacm-nid-cp-security-baseline], [I-D.ietf-xia-sacm-nid-dp-
   security-baseline], [I-D.ietf-xia-sacm-nid-app-infr-layers-security-
   baseline], respectively.

2.  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].

3.  Terminology

   This document uses the terms defined in YANG - A Data Modeling
   Language for the Network Configuration Protocol (NETCONF) [RFC6020] .

4.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is as
   follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Abbreviations before data node names: "rw" means configuration
      (read-write) and "ro" state data (read-only).



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   o  Symbols after data node names: "?" means an optional node, "!"
      means a presence container, and "*" denotes a "list" and "leaf-
      list".

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

5.  Data Model Structure

   To provide security in management plane of network infrastructure
   devices, strict access control, secure access channel, implementing
   secure protocol and cryptographic algorithms, logging system
   operations and secure file management are needed.

   The following parts describe several key points of management plane
   security baseline, such as how to prevent unauthenticated access and
   SNMP attacks, how to authenticate and authorize user, and how to
   safely manage device information and files.  Both security
   configuration and runtime state of security controls are included in
   the following YANG tree diagrams.

5.1.  User Interface Security

   User interfaces of network infrastructure devices provide venues for
   user login and configuration operations.  Typically, there are two
   ways to log in the device, one way is connecting the device directly
   by console port, another is connecting to the device remotely.  Thus,
   network infrastructure devices support console user interface and
   virtual type terminal user interface.  The security configuration of
   user interface includes user authentication and authorization.  User
   authentication configuration is to determine which kind of
   authentication method should be used, such as password only for
   console login, aaa for remote user login.  User authorization
   configuration is to determine the user with which level of privilege
   can successfully log into the device.  For virtual type terminal user
   interface, other security controls can be enforced, such as blocking
   ip addresses after failing authentication, clearing authentication
   request that has been pending for a certain time when the amount of
   authentication requests reaches the limit.









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   module:ietf-user-interface-security
        +--rw user-interface-security
           +--rw (user-interface-type)
              +--:(console)
              |  +--rw user-authen-type       user-authen-type
              |  +--rw user-level             uint8
              +--:(vty)
                 +--rw user-authen-type       user-authen-type
                 +--rw user-level             uint8
                 +--rw ip-block?
                 |  +--rw ip-failed-times     uint8
                 |  +--rw ip-failed-period    uint8
                 |  +--rw ip-reactive-time    uint16
                 +--ro ip-block-list*? [blocked-ip]
                 |  +--ro blocked-ip          inet:ip-address
                 |  +--ro blokced-ip-vpn      string
                 |  +--ro unblocke-interval   uint16
                 +--rw request-limit-renew?
                    +--rw pend-time-limit     uint8

5.2.  Remote Login Security

   There are many access channels such as tlenet, ssh to log in the
   device through remote connection.  For different ways of connection,
   one common thing is that security configuration need to be enforced.
   The access requirements of services must be met preferentially based
   on service requirement analysis.  When an access requirement has
   multiple access channels, the insecure access channels must be
   discarded and the secure channels must be selected.  For example, it
   is strongly recommended that SSH channel should be used instead of
   Telnet for remote login, SFTP should be used instead of FTP for file
   transfer.  If insecure access channels have to be used, several
   security configuration can be enforced to provide basic security
   control.

   Access control is an important part in remote login security,
   different access channels can define different access control
   policies according to service requirements.  Access Control List
   (ACL) is usually used as a basic element for the forwarding behaviour
   configuration of network infrastructure devices.  In this document,
   access control list is also used to enforce security policies on
   network infrastructure devices.  Network Access Control List (ACL)
   YANG Data Model [I-D.ietf-netmod-acl-model] describes the "ietf-
   access-control-list" module to generally define the commonly used ACL
   components.  The "ietf-remote-login-security" module defined in this
   section, imports the "ietf-access-control-list" module.  The derived
   type "acl-type" is used.




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   module:ietf-remote-login-security
        +--rw remote-login-security
           +--rw (remote-login-channel)
              +--:(telnet)
              |  +--rw telnet!
              |     +--rw telnet-authen-type          user-authen-type
              |     +--rw source-interface?           uint16
              |     +--rw {common remote login params}
              +--:(ftp)
              |  +--rw ftp!
              |     +--rw ftp-authen-type             user-authen-type
              |     +--rw ftp-source-interface?
              |     |  +--rw ftp-source-ip?           inet:ip-address
              |     |  +--rw ftp-source-port-type     port-type
              |     |  +--rw ftp-source-port          inet:port-number
              |     +--rw {common remote login params}
              +--:(ssh)
                 +--rw ssh!
                    +--rw ssh-service-type            ssh-service-type
                    +--rw ssh-authen-type             ssh-authenn-type
                    +--rw source-interface?           uint16
                    +--rw rekey-interval?             uint16
                    +--rw authen-retry-times?         uint8
                    +--rw ssh-cipher                  cipher-type
                    +--rw ssh-hmac                    hmac-type
                    +--rw ssh-key-exchange            key-exchange-type
                    +--rw {common remote login params}

   The "{common remote login params}" are:

   {common remote login params}
        +--rw listening-port?            inet:port-number
        +--rw timeout?                   uint16
        +--rw acl*? [acl-name acl-type]
        |  +--rw acl-name                string
        |  +--rw acl-type                acl:acl-type
        +--rw ip-block?
        |  +--rw ip-failed-times          uint8
        |  +--rw ip-failed-period         unit8
        |  +--rw ip-reactive-time         uint16
        +--ro ip-block-list?
        |  +--ro blocked-ip               inet:ip-address
        |  +--ro blokced-ip-vpn           string
        |  +--ro unblocke-interval        uint16
        +--rw login-failed-threshold-alarm?
           +--rw upper-limit              uint8
           +--rw lower-limit              uint8
           +--rw period                   uint16



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5.3.  snmp management security

   Simple Network Management Protocol (SNMP) is a network management
   standard for monitoring managed network devices.  Three SNMP versions
   are available: SNMPv1, SNMPv2c, and SNMPv3.RFC7407 [RFC7407] (A YANG
   Data Model for SNMP Configuration) has defined community-based
   security model for SNMPv1 and SNMPv2c, view-based access control
   model and user-based security model for SNMPv3.  The following module
   "ietf-snmp-management-security" reuses the security control related
   submodules defined in RFC7407 for SNMP security configuration.

module:ietf-snmp-management-security
     +--rw snmp-management-security
        +--rw target* [name]
        |  +--rw name                      snmp:identifier
        |  +--rw (transport)
        |  |  +--:(udp)
        |  |  |  +--rw udp
        |  |  |     +--rw ip               inet:ip-address
        |  |  |     +--rw port?            inet:port-number
        |  |  |     +--rw prefix-length?   uint8
        |  |  +--:(tls)
        |  |  |  +--rw tls
        |  |  |     +-- {common (d)tls transport params}
        |  |  +--:(dtls)
        |  |  |  +--rw dtls
        |  |  |      +-- {common (d)tls transport params}
        |  |  +--:(ssh)
        |  |     +--rw ssh
        |  |     +--rw ip inet:host
        |  |     +--rw port? inet:port-number
        |  |     +--rw username? string
        |  +--rw tlstm
        |  |  +--rw cert-to-name* [id]
        |  |     +--rw id                  uint32
        |  |     +--rw fingerprint         x509c2n:tls-fingerprint
        |  |     +--rw map-type            identityref
        |  |     +--rw name                string
        |  +--rw tag*                      snmp:identifier
        |  +--rw timeout?                  uint32
        |  +--rw retries?                  uint8
        |  +--rw target-params             snmp:identifier
        +--rw target-params* [name]
        |  +--rw name                      snmp:identifier
        |  +--rw (params)?
        |     +--:(v1)
        |     |  +--rw v1
        |     |     +--rw security-name    snmp:security-name



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        |     +--:(v2c)
        |     |  +--rw v2c
        |     |     +--rw security-name    snmp:security-name
        |     +--:(usm)
        |     |   +--rw usm
        |     |      +--rw user-name       snmp:security-name
        |     |      +--rw security-level  security-level
        |     +--:(tsm)
        |         +--rw tsm
        |            +--rw security-name   snmp:security-name
        |            +--rw security-level  security-level
        +--rw community* [index]
        |   +--rw index                    snmp:identifier
        |   +--rw (name)?
        |   |  +--:(text-name)
        |   |  |  +--rw text-name?         string
        |   |  +--:(binary-name)
        |   |     +--rw binary-name?       binary
        |   +--rw security-name            snmp:security-name
        |   +--rw engine-id?               snmp:engine-id
        |   +--rw context?                 snmp:context-name
        |   +--rw target-tag?              snmp:identifier
        +--rw vacm
        |   +--rw group* [name]
        |   |  +--rw name                 group-name
        |   |  +--rw member* [security-name]
        |   |  |  +--rw security-name     snmp:security-name
        |   |  |  +--rw security-model*   snmp:security-model
        |   |  +--rw access* [context security-model security-level]
        |   |     +--rw context           snmp:context-name
        |   |     +--rw context-match?    enumeration
        |   |     +--rw security-model    snmp:security-model-or-any
        |   |     +--rw security-level    snmp:security-level
        |   |     +--rw read-view?        view-name
        |   |     +--rw write-view?       view-name
        |   |     +--rw notify-view?      view-name
        |   +--rw view* [name]
        |      +--rw name                 view-name
        |      +--rw include*             snmp:wildcard-object-identifier
        |      +--rw exclude*             snmp:wildcard-object-identifier
        +--rw usm
        |   +--rw local
        |   |  +--rw user* [name]
        |   |     +-- {common user params}
        |   +--rw remote* [engine-id]
        |      +--rw engine-id            snmp:engine-id
        |      +--rw user* [name]
        |         +-- {common user params}



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        +--rw tsm
           +--rw use-prefix?             boolean


   The "{common user params}" are:

   {common user params}
        +--rw name    snmp:identifier
        +--rw auth!
        |  +--rw (protocol)
        |     +--:(md5)
        |     |  +--rw md5
        |     |     +-- rw key    yang:hex-string
        |     +--:(sha)
        |        +--rw sha
        |           +-- rw key    yang:hex-string
        +--rw priv!
           +--rw (protocol)
              +--:(des)
              |  +--rw des
              |     +-- rw key    yang:hex-string
              +--:(aes)
                 +--rw aes
                    +-- rw key    yang:hex-string

   The "{common (d)tls transport params}" are:

   {common (d)tls transport params}
         +--rw ip?                   inet:host
         +--rw port?                 inet:port-number
         +--rw client-fingerprint?   x509c2n:tls-fingerprint
         +--rw server-fingerprint?   x509c2n:tls-fingerprint
         +--rw server-identity?      snmp:admin-string

5.4.  AAA

   For user management, AAA provides three types of security services,
   authentication, authorization and accounting.  In AAA user
   management, RADIUS (Remote Authentication Dial In User Service) or
   TACACS (Terminal Access Controller Access Control System) can be used
   for remote authentication and authorization of users.  Besides, local
   authentication can also be used.









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module:ietf-aaa
        +--rw aaa
           +--rw reauthorize!
           |  +--rw user-name                                    string
           |  +--rw user-group-name                              string
           +--rw authentication-scheme* [authentication-scheme-name]
           |  +--rw authentication-scheme-name                   string
           |  +--rw authentication-mode                          authentication-mode
           |  +--rw authening-fail?
           |  |  +--rw authening-fail-action                     authening-fail-action
           |  |  +--rw authening-fail-online-domain?             string
           |  +--rw authen-redirect?
           |  |  +--rw authen-redirect-domain                    string
           |  +--rw mac-authentication                           boolean
           +--rw authorization-scheme* [authorization-scheme-name]
           |  +--rw authorization-scheme-name                    string
           |  +--rw authorization-mode                           authorization-mode
           |  +--rw authorization-cmd-level                      uint8
           |  +--rw authorization-cmd-no-response
           |     +--rw no-response-action                        no-response-action
           |     +--rw max-times                                 uint8
           +--accounting-scheme* [accounting-scheme-name]
              +--rw accounting-scheme-name                       string
              +--rw accounting-mode                              accounting-mode
              +--rw accounting-interim-interval
                 +--rw interval                                  uint32
                 +--rw traffic?                                  boolean
                 +--rw hash?                                     boolean

5.5.  Log Security

   Logs record information such as user operations on devices and device
   running status.  Stored as log files on devices, logs help network
   administrators monitor the running status of routers and diagnose
   network faults.  The log records can be outputted to console, or
   stored locally, or outputted to remote Syslog server.  The following
   defined "ietf-log-security" module reuses the security related
   submodules of A YANG Data Model for Syslog Configuration
   [I-D.ietf-netmod-syslog-model], and adds security configurations to
   provide confidentiality and integrity for locally stored log files.











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module:ietf-log-security
     +--rw log-security
        +--rw (log-mode)
           +--:(file)?
           |  +--rw user-level-for-read                  uint8
           |  +--rw log-file-protection-type
           |     +--rw file-encryption?
           |     |  +--rw file-encryption-cypher         cypher-type
           |     +--rw file-integrity?
           |        +--rw file-integrity-algorithm       integrity-algorithm
           +--:(remote)?
              ...
              +--rw (transport)
              |  ...
              |  +--:(tls)
              |     +--rw tls
              |        +--rw server-auth
              |        |  +--rw trusted-ca-certs?        -> /ks:keystore/trusted-certificates/name
              |        |  +--rw trusted-server-certs?    -> /ks:keystore/trusted-certificates/name
              |        +--rw client-auth
              |        |  +--rw (auth-type)?
              |        |     +--:(certificate)
              |        |        +--rw certificate?       -> /ks:keystore/keys/key/certificates/certificate/name
              |        +--rw hello-params {tls-client-hello-params-config}?
              |        |  +--rw tls-versions
              |        |  |  +--rw tls-version*          identityref
              |        |  +--rw cipher-suites
              |        |     +--rw cipher-suite*         identityref
              |        +--rw address?                    inet:host
              |        +--rw port?                       inet:port-number
              +--rw signing-options! {signed-messages}?
                 +--rw cert-signers
                    +--rw cert-signer* [name]
                    |  +--rw name                        string
                    |  +--rw certificate?                -> /ks:keystore/keys/key/certificates/certificate/name
                    |  +--rw hash-algorithm?             enumeration
                    +--rw cert-initial-repeat?           uint32
                    +--rw cert-resend-delay?             uint32
                    +--rw cert-resend-count?             uint32
                    +--rw sig-max-delay?                 uint32
                    +--rw sig-number-resends?            uint32
                    +--rw sig-resend-delay?              uint32
                    +--rw sig-resend-count?              uint32








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5.6.  File Security

   Patches, packages, configuration files are critical system files for
   network infrastructure devices.  To provide security, only users
   under certain security levels are allowed to access these files, but
   cannot delete or modify them.  For configuration files, only users
   with certain configuration rights can modify them.

   module:ietf-file-security
        +--rw file-security
           +--rw user-level-for-read             uint8
           +--rw (file-type)
              +--:(patch)
              |  +--rw patch-verify-type         file-verify-type
              |  +--rw patch-protection-type     file-protection-type
              +--:(package)
              |  +--rw package-verify-type       file-verify-type
              |  +--rw package-protection-type   file-protection-type
              +--:(configuration-file)
                 +--rw user-level-for-modify     uint8

6.  Acknowledgements

7.  IANA Considerations

   This document requires no IANA actions.

8.  Security Considerations

   TBD

9.  References

9.1.  Normative References

   [I-D.ietf-birkholz-sacm-yang-content]
              Birkholz, H. and N. Cam-Winget, "YANG subscribed
              notifications via SACM Statements", 2017,
              <https://datatracker.ietf.org/doc/
              draft-birkholz-sacm-yang-content/>.

   [I-D.ietf-netmod-acl-model]
              Bogdanovic, D., Jethanandani, M., Huang, L., Agarwal, S.,
              and D. Blair, "Network Access Control List(ACL) YANG Data
              Model", 2017, <https://tools.ietf.org/pdf/
              draft-ietf-netmod-acl-model-11.pdf>.





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   [I-D.ietf-netmod-syslog-model]
              Wildes, C. and K. Koushik, "A YANG Data Model for Syslog
              Configuration", 2017, <https://tools.ietf.org/pdf/
              draft-ietf-netmod-syslog-model-16.pdf>.

   [I-D.ietf-sacm-information-model]
              Waltermire, D., Watson, K., Kahn, C., Lorenzin, L., Cokus,
              M., Haynes, D., and H. Birkholz, "SACM Information Model",
              2017, <https://datatracker.ietf.org/doc/
              draft-ietf-sacm-information-model/>.

   [RFC7407]  Bjorklund, M. and J. Schoenwaelder, "A YANG Data Model for
              SNMP Configuration", RFC 7407, DOI 10.17487/RFC7407,
              December 2014, <https://www.rfc-editor.org/info/rfc7407>.

9.2.  Informative References

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

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

Authors' Addresses

   Qiushi Lin
   Huawei
   Huawei Industrial Base
   Shenzhen, Guangdong  518129
   China

   Email: linqiushi@huawei.com


   Liang Xia
   Huawei
   101 Software Avenue, Yuhuatai District
   Nanjing, Jiangsu  210012
   China

   Email: Frank.xialiang@huawei.com






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