Network Working Group J. Jeong
Internet-Draft E. Kim
Intended status: Standards Track Sungkyunkwan University
Expires: January 3, 2019 T. Ahn
Korea Telecom
R. Kumar
Juniper Networks
S. Hares
Huawei
July 2, 2018

I2NSF Consumer-Facing Interface YANG Data Model
draft-ietf-i2nsf-consumer-facing-interface-dm-01

Abstract

This document describes a YANG data model for the Consumer-Facing Interface between an Interface to Network Security Functions (I2NSF) User and Security Controller in an I2NSF system in a Network Functions Virtualization (NFV) environment. The data model is required for enabling different users of a given I2NSF system to define, manage, and monitor security policies for specific flows within an administrative domain.

Status of This Memo

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This Internet-Draft will expire on January 3, 2019.

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Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved.

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Table of Contents

1. Introduction

This document provides a YANG [RFC6020] data model that defines the required data for the Consumer-Facing Interface between an Interface to Network Security Functions (I2NSF) User and Security Controller in an I2NSF system [i2nsf-framework] in a Network Functions Virtualization (NFV) environment. The data model is required for enabling different users of a given I2NSF system to define, manage and monitor security policies for specific flows within an administrative domain. This document defines a YANG data model based on the information model of I2NSF Consumer-Facing Interface [client-facing-inf-im].

Data models are defined at a lower level of abstraction and provide many details. They provide details about the implementation of a protocol’s specification, e.g., rules that explain how to map managed objects onto lower-level protocol constructs. Since conceptual models can be implemented in different ways, multiple data models can be derived by a single information model.

The efficient and flexible provisioning of network functions by NFV leads to a rapid advance in the network industry. As practical applications, network security functions (NSFs), such as firewall, intrusion detection system (IDS)/intrusion protection system (IPS), and attack mitigation, can also be provided as virtual network functions (VNF) in the NFV system. By the efficient virtual technology, these VNFs might be automatically provisioned and dynamically migrated based on real-time security requirements. This document presents a YANG data model to implement security functions based on NFV.

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 [RFC3444].

3. Terminology

This document uses the terminology described in [i2nsf-terminology][client-facing-inf-im][client-facing-inf-req].

4. Data Modeling for Security Policies for Consumer-Facing Interface

The main objective of this data model is to fully transform the information model [client-facing-inf-im] into a YANG data model that can be used for delivering control and management messages via the Consumer-Facing Interface between an I2NSF User and Security Controller for the I2NSF User's high-level security policies.

The semantics of the data model must be aligned with the information model of the Consumer-Facing Interface. The transformation of the information model was performed so that this YANG data model can facilitate the efficient delivery of the control or management messages.

This data model is designed to support the I2NSF framework that can be extended according to the security needs. In other words, the model design is independent of the content and meaning of specific policies as well as the implementation approach. This document suggests a VoIP/VoLTE security service as a use case for policy rule generation.

 
                        +-----------------+       +-----------------+                      
                        |                 |       |                 |                      
                        | Consumer Facing +------>+ Consumer Facing |
                        |    Interface    |       |    Interface    |       
                        |Information Model|       |    Data Model   |
                        +--------+--------+       +-----------------+
                                 ^
                                 |
                                 |
                   +-------------+-------------+
                   |                           |
                   |       Policy-general      |
                   |                           |
                   +-------------+-------------+
                                 ^                                                                                  
                                 |                                                    
      +------------+-------------+------------+--------------+               
      |            |             |            |              |               
+-----+----+  +----+-----+  +----+----+  +----+----+  +------+-----+       
|          |  |          |  |         |  |         |  |            |       
|  Multi   |  | Endpoint |  |  Policy |  | Threat  |  | Telemetry  |
| tenancy  |  |  groups  |  |         |  |  feed   |  |    data    |       
+----------+  +----------+  +----+----+  +---------+  +------------+                                   
                                 ^
                                 |
                                 |
                          +------+------+
                          |             |
                          |     Rule    |
                          |             |
                          +------+------+
                                 ^
                                 |
                +----------------+----------------+
                |                |                |
         +------+------+  +------+------+  +------+------+ 
         |             |  |             |  |             | 
         |    Event    |  |  Condition  |  |    Action   | 
         |             |  |             |  |             | 
         +-------------+  +-------------+  +-------------+ 
        

Figure 1: High-level-abstraction for Consumer Facing Interface

Multi-tenancy in this document enables multiple administrative domains in order to manage application resources. An Enterprise organization may have multiple tenants or departments such as HR, finance, and legal. Thus, we need an object which defines a set of permissions assigned to a user in an organization that wants to manage its own Security Policies. You can think of it as a way to assign policy users to a job function or a set of permissions within the organization. The policy-role object SHALL have Name, Date and access-profile to grant or deny permissions for the perpose of security policy management.

module: policy-general
    +--rw policy
    |  +--rw rule* [rule-id]
    |     +--rw rule-id                      uint16
    |     +--rw name?                        string
    |     +--rw date?                        yang:date-and-time
    |     +--rw case?                        string
    |     +--rw event* [event-id]
    |     |  +--rw event-id                  string
    |     |  +--rw name?                     string
    |     |  +--rw date?                     yang:date-and-time
    |     |  +--rw event-type?               string
    |     |  +--rw time-information?         string
    |     |  +--rw event-map-group?    -> /threat-feed/event-map-group
    |     |                               /event-map-group-id
    |     |  +--rw enable?                   boolean
    |     +--rw condition* [condition-id]
    |     |  +--rw condition-id              string
    |     |  +--rw source?                   string
    |     |  +--rw destination?              string
    |     |  +--rw match?                    boolean
    |     |  +--rw match-direction?          string
    |     |  +--rw exception?                string
    |     +--rw policy-action* [policy-action-id]
    |        +--rw policy-action-id          string
    |        +--rw name?                     string
    |        +--rw date?                     yang:date-and-time
    |        +--rw primary-action?           string
    |        +--rw secondary-action?         string
    |        +--rw owner?                    string
    +--rw multi-tenancy
    |  +--rw policy-domain* [policy-domain-id]
    |  |  +--rw policy-domain-id             uint16
    |  |  +--rw name                         string
    |  |  +--rw address?                     string
    |  |  +--rw contact                      string
    |  |  +--rw date                         yang:date-and-time
    |  |  +--rw policy-tenant* [policy-tenant-id]
    |  |  |  +--rw policy-tenant-id          uint16
    |  |  |  +--rw name                      string
    |  |  |  +--rw date                      yang:date-and-time
    |  |  |  +--rw domain?               ->  /multi-tenancy
    |  |  |                                  /policy-domain
    |  |  |                                  /policy-domain-id
    |  |  +--rw authentication-method?   ->  /multi-tenancy
    |  |                                     /policy-mgnt-auth-method
    |  |                                     /policy-mgnt-auth-method-id
    |  +--rw policy-role* [policy-role-id]
    |  |  +--rw policy-role-id               uint16
    |  |  +--rw name                         string
    |  |  +--rw date                         yang:date-and-time
    |  |  +--rw access-profile               string
    |  +--rw policy-user* [policy-user-id]
    |  |  +--rw policy-user-id               uint16
    |  |  +--rw name                         string
    |  |  +--rw date                         yang:date-and-time
    |  |  +--rw password                     string
    |  |  +--rw email                        string
    |  |  +--rw scope-type?                  string
    |  |  +--rw scope-reference?             string
    |  |  +--rw role                         string
    |  +--rw policy-mgnt-auth-method* [policy-mgnt-auth-method-id]
    |     +--rw policy-mgnt-auth-method-id   uint16
    |     +--rw name                         string
    |     +--rw date                         yang:date-and-time
    |     +--rw authentication-method        enumeration
    |     +--rw mutual-authentication        boolean
    |     +--rw token-server                 inet:ipv4-address
    |     +--rw certificate-server           inet:ipv4-address
    |     +--rw single-sing-on-server        inet:ipv4-address
    +--rw endpoint-group
    |  +--rw meta-data-source* [meta-data-source-id]
    |  |  +--rw meta-data-source-id          uint16
    |  |  +--rw name                         string
    |  |  +--rw date                         yang:date-and-time
    |  |  +--rw tag-type?                    boolean
    |  |  +--rw tag-server-information?      inet:ipv4-address
    |  |  +--rw tag-application-protocol?    string
    |  |  +--rw tag-server-credential?       string
    |  +--rw user-group* [user-group-id]
    |  |  +--rw user-group-id                uint16
    |  |  +--rw name?                        string
    |  |  +--rw date?                        yang:date-and-time
    |  |  +--rw group-type?                  enumeration
    |  |  +--rw meta-data-server?            inet:ipv4-address
    |  |  +--rw group-member?                string
    |  |  +--rw risk-level?                  uint16
    |  +--rw device-group* [device-group-id]
    |  |  +--rw device-group-id              uint16
    |  |  +--rw name?                        string
    |  |  +--rw date?                        yang:date-and-time
    |  |  +--rw group-type?                  enumeration
    |  |  +--rw meta-data-server?            inet:ipv4-address
    |  |  +--rw group-member?                string
    |  |  +--rw risk-level?                  uint16
    |  +--rw application-group* [application-group-id]
    |  |  +--rw application-group-id         uint16
    |  |  +--rw name?                        string
    |  |  +--rw date?                        yang:date-and-time
    |  |  +--rw group-type?                  enumeration
    |  |  +--rw meta-data-server?            inet:ipv4-address
    |  |  +--rw group-member?                string
    |  |  +--rw risk-level?                  uint16
    |  +--rw location-group* [location-group-id]
    |     +--rw location-group-id            uint16
    |     +--rw name?                        string
    |     +--rw date?                        yang:date-and-time
    |     +--rw group-type?                  enumeration
    |     +--rw meta-data-server?            inet:ipv4-address
    |     +--rw group-member?                string
    |     +--rw risk-level?                  uint16
    +--rw threat-feed
    |  +--rw threat-feed* [threat-feed-id]
    |  |  +--rw threat-feed-id               uint16
    |  |  +--rw name?                        string
    |  |  +--rw date?                        yang:date-and-time
    |  |  +--rw feed-type                    enumeration
    |  |  +--rw feed-server?                 inet:ipv4-address
    |  |  +--rw feed-priority?               uint16
    |  +--rw custom-list* [custom-list-id]
    |  |  +--rw custom-list-id               uint16
    |  |  +--rw name?                        string
    |  |  +--rw date?                        yang:date-and-time
    |  |  +--rw list-type                    enumeration
    |  |  +--rw list-property                enumeration
    |  |  +--rw list-content?                string
    |  +--rw malware-scan-group* [malware-scan-group-id]
    |  |  +--rw malware-scan-group-id        uint16
    |  |  +--rw name?                        string
    |  |  +--rw date?                        yang:date-and-time
    |  |  +--rw signature-server?            inet:ipv4-address
    |  |  +--rw file-types?                  string
    |  |  +--rw malware-signatures?          string
    |  +--rw event-map-group* [event-map-group-id]
    |     +--rw event-map-group-id           uint16
    |     +--rw name?                        string
    |     +--rw date?                        yang:date-and-time
    |     +--rw security-events?             string
    |     +--rw threat-map?                  string
    +--rw telemetry-data
       +--rw telemetry-data* [telemetry-data-id]
       |  +--rw telemetry-data-id            uint16
       |  +--rw name?                        string
       |  +--rw date?                        yang:date-and-time
       |  +--rw logs?                        boolean
       |  +--rw syslogs?                     boolean
       |  +--rw snmp?                        boolean
       |  +--rw sflow?                       boolean
       |  +--rw netflow?                     boolean
       |  +--rw interface-stats?             boolean
       +--rw telemetry-source* [telemetry-source-id]
       |  +--rw telemetry-source-id          uint16
       |  +--rw name?                        string
       |  +--rw date?                        yang:date-and-time
       |  +--rw source-type?                 enumeration
       |  +--rw nsf-source?                  inet:ipv4-address
       |  +--rw nsf-credentials?             string
       |  +--rw collection-interval?         uint16
       |  +--rw collection-method?           enumeration
       |  +--rw heartbeat-interval?          uint16
       |  +--rw qos-marking?                 uint16
       +--rw telemetry-destination* [telemetry-destination-id]
          +--rw telemetry-destination-id     uint16
          +--rw name?                        string
          +--rw date?                        yang:date-and-time
          +--rw collector-source?            inet:ipv4-address
          +--rw collector-credentials?       string
          +--rw data-encoding?               string
          +--rw data-transport?              enumeration

              
        

Figure 2: Generic Data Model for Security Policies for cf Interface

5. YANG Data Model for Security Policies for Consumer-Facing Interface

This section describes a YANG data model for Consumer-Facing Interface, based on the information model of Consumer-Facing Interface to security controller [client-facing-inf-im].

<CODE BEGINS> file "policy-general.yang"
module ietf-policy-general {
  namespace
    "urn:ietf:params:xml:ns:yang:ietf-policy-general";
  prefix
    cf-interface;
      
  import ietf-yang-types{
    prefix yang;
  }

  import ietf-inet-types{
    prefix inet;
  }
      
  organization
    "IETF I2NSF (Interface to Network Security Functions) 
     Working Group";

  contact
    "WG Web: <http://tools.ietf.org/wg/i2nsf>
     WG List: <mailto:i2nsf@ietf.org>

     WG Chair: Adrian Farrel
     <mailto:Adrain@olddog.co.uk>

     WG Chair: Linda Dunbar
     <mailto:Linda.duhbar@huawei.com>

     Editor: Jaehoon Paul Jeong
     <mailto:pauljeong@skku.edu>";
        
  description
    "This module defines a YANG data module for consumer-facing 
     interface to security controller.";

  revision "2018-07-02"{
    description "fourth revision";
    reference
      "draft-kumar-i2nsf-client-facing-interface-im-04";
  }
    
  //Groupings
  container policy {
    description
    "This object is a policy instance to have
    complete information such as where and when
    a policy need to be applied.";
 
    list rule {
     key "rule-id";
     leaf rule-id {
     type uint16;
     description
     "This is ID for rules.";
    }
      description
      "This is a container for rules.";
      leaf name {
       type string;
        description
         "This field idenfifies the name of this object.";
      }

      leaf date {
       type yang:date-and-time;
        description
         "Date this object was created or last 
          modified";
      }

      leaf case {
       type string;
        description
         "to identify whether the rule belongs to
         web filter or enterprise mode.";
      }

      list event {
       key "event-id";
       description
       "This represents the security event of a
       policy-rule.";
    
       leaf event-id {
       type string;
       mandatory true;
       description
       "This represents the event-id.";
       }
     
       leaf name {
        type string;
         description
          "This field idenfifies the name of this object.";
       }
     
       leaf date {
        type yang:date-and-time;
        description
         "Date this object was created or last 
          modified";
       }
     
       leaf event-type {
        type string;
         description
          "This field identifies the event of 
          policy enforcement trigger type.";
       }
     
       leaf time-information {
        type string;
        description
         "This field contains time calendar such as
         BEGIN-TIME and END-TIME for one time 
         enforcement or recurring time calendar for 
         periodic enforcement.";
       }
     
       leaf event-map-group {
        type leafref {
        path "/threat-feed/event-map-group/event-map-group-id";
        }
        description
        "This field contains security events or threat
        map in order to determine when a policy need 
        to be activated. This is a reference to
        Evnet-Map-Group.";
       }
     
       leaf enable {
        type boolean;
         description
          "This determines whether the condition
          matches the security event or not.";
       }
     }
     
     list condition {
      key "condition-id";
      description
      "This represents the condition of a
      policy-rule.";
     
      leaf condition-id {
       type string;
       description
       "This represents the condition-id.";
      }
     
      leaf source {
       type string;
        description
        "This field identifies the source of
        the traffic. This could be reference to 
        either 'Policy Endpoint Group' or 
        'Threat-Feed' or 'Custom-List' if Security 
        Admin wants to specify the source; otherwise, 
        the default is to match all traffic.";
      }
 
      leaf destination {
       type string;
        description
         "This field identifies the source of
          the traffic. This could be reference to 
          either 'Policy Endpoint Group' or 
          'Threat-Feed' or 'Custom-List' if Security 
          Admin wants to specify the source; otherwise, 
          the default is to match all traffic.";
      }
 
      leaf match {
       type boolean;
        description
         "This field identifies the match criteria used to
         evaluate whether the specified action need to be 
         taken or not.  This could be either a Policy-
         Endpoint-Group identifying a Application set or a 
         set of traffic rules.";
      }
 
      leaf match-direction {
       type string;
        description
         "This field identifies if the match criteria is
         to evaluated for both direction of the traffic or
         only in one direction with default of allowing in
         the other direction for stateful match conditions.
         This is optional and by default rule should apply 
         in both directions.";
      }
 
      leaf exception {
       type string;
        description
         "This field identifies the exception 
         consideration when a rule is evaluated for a 
         given communication.  This could be reference to 
         Policy-Endpoint-Group object or set of traffic 
         matching criteria.";
      }
     }

     list policy-action {
      key "policy-action-id";
     
      leaf policy-action-id {
      type string;
      mandatory true;
       description
        "this represents the policy-action-id.";
      }
      description
       "This object represents actions that a 
       Security Admin wants to perform based on 
       a certain traffic class.";
     
      leaf name {
       type string;
        description
         "The name of the policy-action object.";
      }

      leaf date {
       type yang:date-and-time;
        description
         "When the object was created or last 
         modified.";
      }

      leaf primary-action {
       type string;
        description
         "This field identifies the action when a rule
         is matched by NSF. The action could be one of
         'PERMIT', 'DENY', 'RATE-LIMIT', 'TRAFFIC-CLASS', 
         'AUTHENTICATE-SESSION', 'IPS, 'APP-FIREWALL', etc.";
      }

      leaf secondary-action {
       type string;
        description
         "This field identifies additional actions if
         a rule is matched. This could be one of 'LOG',
         'SYSLOG', 'SESSION-LOG', etc.";
      }
        

      leaf owner {
       type string;
        description
         "This field defines the owner of this 
         policy. Only the owner is authorized to 
         modify the contents of the policy.";
      }
     }
    }
 }   

     container multi-tenancy {
        description
          "The descriptions of multi-tenancy.";

        list policy-domain {
          key "policy-domain-id";
        
          leaf policy-domain-id {
            type uint16;
            description
              "This represents the list of domains.";
          }
          description
          "this represent the list of policy domains";
          leaf name {
            type string;
            mandatory true;
            description
              "Name of the organization or customer representing 
              this domain.";
          }

          leaf address {
            type string;
            description
              "address of an organization or customer.";
          }

          leaf contact {
            type string;
            mandatory true;
            description
              "contact information of the organization
               or customer.";
          }

          leaf date {
            type yang:date-and-time;
            mandatory true;
            description
              "The date when this account was created 
              or last modified.";
          }
          list policy-tenant {
            key "policy-tenant-id";
            leaf policy-tenant-id {
              type uint16;
              description
                "The policy tenant id.";
            }
            description
            "This represents the list of tenants";
      
            leaf name {
              type string;
              mandatory true;
              description
                "Name of the Department or Division within
                 an organization.";
            }

            leaf date {
              type yang:date-and-time;
              mandatory true;
              description
                "Date this account was created or last modified.";
            }

            leaf domain {
              type leafref {
                path "/multi-tenancy/policy-domain/policy-domain-id";
              }
              description
              "This field identifies the domain to which this 
              tenant belongs. This should be reference to a 
              'Policy-Domain’ object.";
            }
          }
          leaf authentication-method {
            type leafref {
              path "/multi-tenancy/policy-mgnt-auth-method/policy-mgnt-auth-method-id";
            }
          
            description
            "Authentication method to be used for this domain.
            It should be a reference to a 'policy-mgmt-auth-method'
            object.";
          }
        }

        list policy-role {
          key "policy-role-id";
        
          leaf policy-role-id {
          type uint16;
          mandatory true;
          description
            "This defines a set of permissions assigned 
            to a user in an organization that want to manage 
            its own Security Policies.";
          }
          description
          "This represents the list of policy roles.";
        
          leaf name {
            type string;
            mandatory true;
            description
              "This field identifies name of the role.";
          }
      
          leaf date {
            type yang:date-and-time;
            mandatory true;
            description
              "Date this role was created or last modified.";
          }

          leaf access-profile {
            type string;
            mandatory true;
            description
              "This field identifies the access profile for the
              role. The profile grants or denies access to policy
              objects.  Multiple access profiles can be 
              concatenated together.";
          }
        }

        list policy-user {
          key "policy-user-id";
        
          leaf policy-user-id {
          type uint16;
          description
            "This represents the policy-user-id.";
          }
          description
          "This represents the list of policy users.";
          leaf name {
            type string;
            mandatory true;
            description
              "The name of a user.";
          }
      
          leaf date {
            type yang:date-and-time;
            mandatory true;
            description
              "Date this user was created or last modified";
          }

          leaf password {
            type string;
            mandatory true;
            description
              "User password for basic authentication";
          }

          leaf email {
            type string;
            mandatory true;
            description
              "The email account of a user";
          }
          
          leaf scope-type {
            type string;
            description
              "identifies whether a user has domain-wide
              or tenant-wide privileges";
          }

          leaf scope-reference {
            type string;
            description
              "This references policy-domain or policy-tenant 
              to identify the scope.";
          }

          leaf role {
            type string;
            mandatory true;
            description
              "This references policy-role to define specific
              permissions";
          }
        }
  
        list policy-mgnt-auth-method {
          key "policy-mgnt-auth-method-id";
          
          leaf policy-mgnt-auth-method-id {
          type uint16;
          description
            "This represents the authentication method id.";
          }
          description
          "The descriptions of policy management
            authentication methods.";
          leaf name {
            type string;
            mandatory true;
            description
              "name of the authentication method";
          }

          leaf date {
            type yang:date-and-time;
            mandatory true;
            description
              "date when the authentication method
              was created";
          }

          leaf authentication-method {
            type enumeration{
              enum password{
                description
                  "password-based authentication.";
              }
              enum token{
                description
                  "token-based authentication.";
              }
              enum certificate{
                description
                  "certificate-based authentication.";
              }
            }
            mandatory true;
            description
              "The description of authentication method; 
              token-based, password, certificate, 
              single-sign-on";
          }
 
          leaf mutual-authentication {
            type boolean;
            mandatory true;
            description
              "To identify whether the authentication
               is mutual";
          }

          leaf token-server {
            type inet:ipv4-address;
            mandatory true;
            description
              "The token-server information if the 
              authentication method is token-based";
          }

          leaf certificate-server {
            type inet:ipv4-address;
            mandatory true;
            description
              "The certificate-server information if 
              the authentication method is certificate-based";
          }

          leaf single-sing-on-server {
            type inet:ipv4-address;
            mandatory true;
            description
              "The single-sign-on-server information 
              if the authentication method is 
              single-sign-on-based";
          }
        }
     }
container endpoint-group {
        description
          "A logical entity in their business 
          environment, where a security policy 
          is to be applied.";

        list meta-data-source {
          key "meta-data-source-id";
          leaf meta-data-source-id {
          type uint16;
          mandatory true;
          description
            "This represents the meta-data source id.";
          }
          description
          "This represents the meta-data source.";
          
          leaf name {
            type string;
            mandatory true;
            description
              "This identifies the name of the 
              meta-datas-ource.";
          }
          
          leaf date {
            type yang:date-and-time;
            mandatory true;
            description
              "This identifies the date this object was 
              created or last modified.";
          }

          leaf tag-type {
            type boolean;
            description
              "This identifies the group type; user group, 
              app group or device group.";
          }

          leaf tag-server-information {
            type inet:ipv4-address;
            description
              "The description of suthentication method; 
              token-based, password, certificate, 
              single-sign-on";
          }

          leaf tag-application-protocol {
            type string;
            description
              "This filed identifies the protocol e.g. LDAP, 
              Active Directory, or CMDB";
          }

          leaf tag-server-credential {
            type string;
            description
              "This field identifies the credential 
              information needed to access the tag server";
          }
        }

        list user-group{
          key "user-group-id";
          
          leaf user-group-id {
          type uint16;
          mandatory true;
          description
            "This represents the the user group id.";
          }
          description
          "This represents the user group.";
          
          leaf name {
            type string;
            description
              "This field identifies the name of user-group.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when this user-group was created or last modified.";
          }

          leaf group-type {
            type enumeration{
              enum user-tag{
                description
                  "The user group is based on user-tag.";
              }
              enum user-name{
                description
                  "The user group is based on user-name.";
              }
              enum ip-address{
                description
                  "The user group is based on ip-address.";
              }
            }

            description
              "This describes the group type; User-tag, 
              User-name or IP-address.";
          }

          leaf meta-data-server {
            type inet:ipv4-address;
            description
              "This references metadata source";
          }

          leaf group-member {
            type string;
            description
              "This describes the user-tag information";
          }

          leaf risk-level {
            type uint16;
            description
              "This represents the threat level; valid range
               may be 0 to 9.";
          }
        }

        list device-group {
          key "device-group-id";
          leaf device-group-id {
          type uint16;
           description
            "This represents a device group id.";
          }
          description
            "This represents a device group.";
          leaf name {
            type string;
          description
              "This field identifies the name of 
              a device-group.";
          }
          leaf date {
            type yang:date-and-time;
            description
            "The date when this group was create or 
            last modified.";
          }

          leaf group-type {
            type enumeration{
              enum device-tag{
                description
                  "The device group is based on device-tag.";
              }
              enum device-name{
                description
                  "The device group is based on device-name.";
              }
              enum ip-address{
                description
                  "The device group is based on ip-address.";
              }
            }
            description
              "This describes the group type; device-tag, 
              device-name or IP-address.";
          }

          leaf meta-data-server {
            type inet:ipv4-address;
            description
              "This references meta-data-source 
              object.";
          }

          leaf group-member {
            type string;
            description
              "This describes the device-tag, device-name or 
              IP-address information";
          }

          leaf risk-level {
            type uint16;
            description
              "This represents the threat level; valid range 
              may be 0 to 9.";
          }
        }

        list application-group{
          key "application-group-id";
          leaf application-group-id {
          type uint16;
          description
          "This represents an application group id.";
          }
          description
          "This represents an application group.";
          leaf name {
            type string;
            description
            "This field identifies the name of 
            an application group";
          }

          leaf date {
            type yang:date-and-time;
            description
            "The date when this group was created or 
            last modified.";
          }

          leaf group-type {
            type enumeration{
              enum application-tag{
                description
                  "The application group is based on application-tag.";
              }
              enum device-name{
                description
                  "The application group is based on application-name.";
              }
              enum ip-address{
                description
                  "The application group is based on ip-address.";
              }
            }
            description
              "This identifies the group type; 
              application-tag, application-name or
              IP-address.";
          }

          leaf meta-data-server {
            type inet:ipv4-address;
            description
              "This references meta-data-source 
              object.";
          }

          leaf group-member {
            type string;
            description
              "This describes the application-tag, 
              application-name or IP-address information";
          }

          leaf risk-level {
            type uint16;
            description
              "This represents the threat level; valid range
               may be 0 to 9.";
          }
        }

        list location-group{
          key "location-group-id";
          leaf location-group-id {
          type uint16;
          description
          "This represents a location group id.";
          }
          description
          "This represents a location group.";
          
          leaf name {
            type string;
            description
            "This field identifies the name of 
            a location group";

          }

          leaf date {
            type yang:date-and-time;
            description
            "The date when this group was created or 
            last modified.";
          }

          leaf group-type {
            type enumeration{
              enum location-tag{
                description
                  "The location group is based on location-tag.";
              }
              enum location-name{
                description
                  "The location group is based on location-name.";
              }
              enum ip-address{
                description
                  "The location group is based on ip-address.";
              }
            }
            description
              "This identifies the group type; 
              location-tag, location-name or
              IP-address.";
          }

          leaf meta-data-server {
            type inet:ipv4-address;
            description
              "This references meta-data-source 
              object.";
          }

          leaf group-member {
            type string;
            description
              "This describes the location-tag, 
              location-name or IP-address information";
          }

          leaf risk-level {
            type uint16;
            description
              "This represents the threat level; valid range
               may be 0 to 9.";
          }
        }
    }

    container threat-feed {
      description
      "this describes the list of threat-feed.";

        list threat-feed {
          key "threat-feed-id";
          leaf threat-feed-id {
          type uint16;
          mandatory true;
          description
            "This represents the threat-feed-id.";
          }
          description
            "This represents the threat feed within the 
            threat-prevention-list.";
          leaf name {
            type string;
            description
              "Name of the theat feed.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the threat-feed was created.";
          }

          leaf feed-type {
            type enumeration {
              enum unknown {
                description
                  "feed-type is unknown.";
              }
              enum ip-address {
                description
                  "feed-type is IP address.";
              }
              enum url {
                description
                  "feed-type is URL.";
              }
            }
            mandatory true; 
            description
              "This determined whether the feed-type is IP address 
              based or URL based.";
          }

          leaf feed-server {
            type inet:ipv4-address;
            description
              "this contains threat feed server information.";
          }

          leaf feed-priority {
            type uint16;
            description
              "this describes the priority of the threat from 
              0 to 5, where 0 means the threat is minimum and
              5 meaning the maximum.";
          }
      }

      list custom-list {
          key "custom-list-id";
          leaf custom-list-id {
          type uint16;
          description
          "this describes the custom-list-id.";
          }
          description
          "this describes the threat-prevention custom list.";
          leaf name {
            type string;
            description
              "Name of the custom-list.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the custom list was created.";
          }

          leaf list-type {
            type enumeration {
              enum unknown {
                description
                  "list-type is unknown.";
              }
              enum ip-address {
                description
                  "list-type is IP address.";
              }
              enum mac-address {
                description
                  "list-type is MAC address.";
              }
              enum url {
                description
                  "list-type is URL.";
              }
            }
            mandatory true; 
            description
              "This determined whether the feed-type is IP address 
              based or URL based.";
          }

         leaf list-property {
            type enumeration {
              enum unknown {
                description
                  "list-property is unknown.";
              }
              enum blacklist {
                description
                  "list-property is blacklist.";
              }
              enum whitelist {
                description
                  "list-property is whitelist.";
              }
            }
            mandatory true; 
            description
              "This determined whether the list-type is blacklist 
              or whitelist.";
          }

          leaf list-content {
            type string;
            description
              "This describes the contents of the custom-list.";
          }
      }

      list malware-scan-group {
          key "malware-scan-group-id";
          leaf malware-scan-group-id {
          type uint16;
          mandatory true;
          description
          "This is the malware-scan-group-id.";
          }
          description
          "This represents the malware-scan-group.";
          leaf name {
            type string;
            description
              "Name of the malware-scan-group.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the malware-scan-group was created.";
          }

          leaf signature-server {
            type inet:ipv4-address;
            description
              "This describes the signature server of the 
              malware-scan-group.";
          }
          
          leaf file-types {
            type string;
            description
              "This contains a list of file types needed to
              be scanned for the virus.";
          }

          leaf malware-signatures {
            type string;
            description
              "This contains a list of malware signatures or hash.";
          }
      }

      list event-map-group {
          key "event-map-group-id";
          leaf event-map-group-id {
          type uint16;
          mandatory true;
          description
          "This is the event-map-group-id.";
          }
          description
          "This represents the event map group.";
      
          leaf name {
            type string;
            description
              "Name of the event-map.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the event-map was created.";
          }

          leaf security-events {
            type string;
            description
              "This contains a list of security events.";
          }

          leaf threat-map {
            type string;
            description
              "This contains a list of threat levels.";
          }
      }
    }

    container telemetry-data {
      description
      "Telemetry provides visibility into the network 
      activities which can be tapped for further 
      security analytics, e.g., detecting potential 
      vulnerabilities, malicious activities, etc.";
      
      list telemetry-data {
        key "telemetry-data-id";
    
        leaf telemetry-data-id {
        type uint16;
        mandatory true;
        description
        "This is ID for telemetry-data-id.";
        }
        description
        "This is ID for telemetry-data.";
    
        leaf name {
          type string;
          description
            "Name of the telemetry-data object.";
        }

        leaf date {
          type yang:date-and-time;
          description
            "This field states when the telemery-data 
            object was created.";
        }

        leaf logs {
          type boolean;
          description
            "This field identifies whether logs 
            need to be collected.";
        }

        leaf syslogs {
          type boolean;
          description
            "This field identifies whether System logs 
            need to be collected.";
        }

        leaf snmp {
          type boolean;
          description
            "This field identifies whether 'SNMP traps' and
            'SNMP alarms' need to be collected.";
        }

        leaf sflow {
          type boolean;
          description
            "This field identifies whether 'sFlow' data 
            need to be collected.";
        }

        leaf netflow {
          type boolean;
          description
            "This field identifies whether 'NetFlow' data 
            need to be collected.";
        }

        leaf interface-stats {
          type boolean;
          description
            "This field identifies whether 'Interface' data 
            such as packet bytes and counts need to be
            collected.";
        }
      }

      list telemetry-source {
        key "telemetry-source-id";
      
        leaf telemetry-source-id {
        type uint16;
        mandatory true;
        description
        "This is ID for telemetry-source-id.";
        }
        description
        "This is ID for telemetry-source.";          
     
        leaf name {
          type string;
          description
            "This identifies the name of this object.";
        }

        leaf date {
          type yang:date-and-time;
            description
              "Date this object was created or last modified";
        }

        leaf source-type {
          type enumeration {
            enum network-nsf {
              description
                "NSF telemetry source type is network-nsf.";
            }
     
            enum firewall-nsf {
              description
                "NSF telemetry source type is firewall-nsf.";
            }
            enum ids-nsf {
              description
                "NSF telemetry source type is ids-nsf.";
            }
            enum ips-nsf {
              description
                "NSF telemetry source type is ips-nsf.";
            }
            enum proxy-nsf {
              description
                "NSF telemetry source type is proxy-nsf.";
            }
            enum other-nsf {
              description
                "NSF telemetry source type is other-nsf.";
            }
          }
          description
            "This should have one of the following type of 
            the NSF telemetry source: NETWORK-NSF, 
            FIREWALL-NSF, IDS-NSF, IPS-NSF, 
            PROXY-NSF, VPN-NSF, DNS, ACTIVE-DIRECTORY,
            IP Reputation Authority, Web Reputation 
            Authority, Anti-Malware Sandbox, Honey Pot, 
            DHCP, Other Third Party, ENDPOINT";
        }

        leaf nsf-source {
          type inet:ipv4-address;
           description
            "This field contains information such as
            IP address and protocol (UDP or TCP) port 
            number of the NSF providing telemetry data.";
        }

        leaf nsf-credentials {
          type string;
          description
            "This field contains username and password 
            to authenticate with the NSF.";
        }

        leaf collection-interval {
          type uint16;
          units seconds;
          default 5000;
          description
            "This field contains time in milliseconds
             between each data collection. For example, 
             a value of 5000 means data is streamed to 
             collector every 5 seconds. Value of 0 means 
             data streaming is event-based";
        }

        leaf collection-method {
          type enumeration {
            enum unknown {
              description
                "collection-method is unknown.";
            }
            enum push-based {
              description
                "collection-method is PUSH-based.";
            }
            enum pull-based {
              description
                "collection-method is PULL-based.";
            }
          }
          description
          "This field contains a method of collection, 
          i.e., whether it is PUSH-based or PULL-based.";
        }
        leaf heartbeat-interval {
          type uint16;
          units seconds;
          description
          "time in seconds the source sends telemetry 
          heartbeat.";
        }

        leaf qos-marking {
          type uint16;
          description
          "DSCP value must be contained in this field.";
        }
      }
  
      list telemetry-destination {
        key "telemetry-destination-id";
  
        leaf telemetry-destination-id {
        type uint16;
        description
        "this represents the telemetry-destination-id";
        }
        description
        "This object contains information related to 
        telemetry destination. The destination is 
        usually a collector which is either a part of
        Security Controller or external system 
        such as Security Information and Event 
        Management (SIEM).";
          
        leaf name {
          type string;
          description
            "This identifies the name of this object.";
        }

        leaf date {
          type yang:date-and-time;
          description
            "Date this object was created or last 
            modified";
        }

          leaf collector-source {
            type inet:ipv4-address;
              description
                "This field contains information such as
                IP address and protocol (UDP or TCP) port 
                number for the collector's destination.";
          }

          leaf collector-credentials {
            type string;
              description
              "This field contains the username and
             password for the collector.";
          }

          leaf data-encoding {
            type string;
             description
              "This field contains the telemetry data encoding 
              in the form of schema.";
          }

          leaf data-transport {
            type enumeration{
              enum grpc {
                description
                  "telemetry data protocol is grpc.";
              }
              enum buffer-over-udp{
                description
                  "telemetry data protocol is buffer over UDP.";
              }
            }
            description
            "This field contains streaming telemetry data 
            protocols. This could be gRPC, protocol
            buffer over UDP, etc.";
          }
      }
    }
  }
<CODE ENDS>
                

Figure 3: YANG for policy-general

6. Security Considerations

The data model for the I2NSF Consumer-Facing Interface is derived from the I2NSF Consumer-Facing Interface Information Model [client-facing-inf-im], so the same security considerations with the information model should be included in this document. The data model needs to support a mechanism to protect Consumer-Facing Interface to Security Controller.

7. Acknowledgments

This work was supported by Institute for Information & communications Technology Promotion(IITP) grant funded by the Korea government(MSIP) (No.R-20160222-002755, Cloud based Security Intelligence Technology Development for the Customized Security Service Provisioning).

This document has greatly benefited from inputs by Hyoungshick Kim, Mahdi F. Dachmehchi, Seungjin Lee, Jinyong Tim Kim, and Daeyoung Hyun.

8. Contributors

I2NSF is a group effort. The following people actively contributed to the consumer facing interface data model, and are considered co-authors: o Hyoungshick Kim (Sungkyunkwan University) o Seungjin Lee (Sungkyunkwan University)

9. References

9.1. Normative References

[RFC3444] Pras, A., "On the Difference between Information Models and Data Models", RFC 3444, January 2003.

9.2. Informative References

[client-facing-inf-im] Kumar, R., Lohiya, A., Qi, D., Bitar, N., Palislamovic, S. and L. Xia, "Information model for Client-Facing Interface to Security Controller", Internet-Draft draft-kumar-i2nsf-client-facing-interface-im-04, July 2017.
[client-facing-inf-req] Kumar, R., Lohiya, A., Qi, D., Bitar, N., Palislamovic, S. and L. Xia, "Requirements for Client-Facing Interface to Security Controller", Internet-Draft draft-ietf-i2nsf-client-facing-interface-req-03, July 2017.
[i2nsf-framework] Lopez, D., Lopez, E., Dunbar, L., Strassner, J. and R. Kumar, "Framework for Interface to Network Security Functions", Internet-Draft draft-ietf-i2nsf-framework-08, October 2017.
[i2nsf-terminology] Hares, S., Strassner, J., Lopez, D., Birkholz, H. and L. Xia, "Information model for Client-Facing Interface to Security Controller", Internet-Draft draft-ietf-i2nsf-terminology-04, July 2017.
[RFC6020] Bjorklund, M., "YANG – A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010.

Appendix A. Changes from draft-ietf-i2nsf-consumer-facing-interface-dm-00

The following changes have been made from draft-jeong-i2nsf-consumer-facing-interface-dm-05:

Appendix B. Use Case: Policy Instance Example for VoIP/VoLTE Security Services

A common scenario for VoIP/VoLTE policy enforcement could be that a malicious call is made to a benign user of any telecommunication company. For example, imagine a case wherea company "A" employs a hacker with a malicious attempt to hack a user's phone with malware. The company "A" is located in a country, such as Africa, and uses the user's hacked phone to call the company. The hacked user is unaware of the company "A" so complains about the international call that was made to the company "B", which is the user's telecommunications company. The company "A" charges the company "B" for the international call. The company "B" cannot charge the user for the call, and has no choice but to pay the company "A". The following shows the example data tree model for the VoIP/VoLTE services. Multi-tenancy, endpoint groups, threat prevention, and telemetry data components are general part of the tree model, so we can just modify the policy instance in order to generate and enforce high-level policies. The policy-calendar can act as a scheduler to set the star and end time to block calls which uses suspicious ids, or calls from other countries.

module: policy-voip
    +--rw policy-voip
    |  +--rw rule-voip* [rule-voip-id]
    |  |  +--rw rule-voip-id           uint16
    |  |  +--rw name?                  string
    |  |  +--rw date?                  yang:date-and-time
    |  |  +--rw event* [event-id]
    |  |  |  +--rw event-id            string
    |  |  |  +--rw name?               string
    |  |  |  +--rw date?               yang:date-and-time
    |  |  |  +--rw event-type?         string
    |  |  |  +--rw Time-Information?   string
    |  |  |  +--rw event-map-group?    -> /threat-feed/event-map-group
    |  |  |                               /event-map-group-id
    |  |  |  +--rw enable?             boolean
    |  |  +--rw condition* [condition-id]
    |  |  |  +--rw condition-id        string
    |  |  |  +--rw source-caller?      -> /threat-feed/threat-feed
    |  |  |                               /threat-feed-id
    |  |  |  +--rw destination-callee? -> /threat-feed/custom-list
    |  |  |                               /custom-list-id
    |  |  |  +--rw match?              boolean
    |  |  |  +--rw match-direction?    string
    |  |  |  +--rw exception?          string
    |  |  +--rw action* [action-id]
    |  |  |  +--rw action-id           string
    |  |  |  +--rw name?               string
    |  |  |  +--rw date?               yang:date-and-time
    |  |  |  +--rw primary-action?     string
    |  |  |  +--rw secondary-action?   string
    |  |  +--rw precedence?            uint16
    |  +--rw owner* [owner-id]
    |     +--rw owner-id               string
    |     +--rw name?                  string
    |     +--rw date?                  yang:date-and-time
    +--rw threat-feed
       +--rw threat-feed* [threat-feed-id]
       |  +--rw threat-feed-id         uint16
       |  +--rw name?                  string
       |  +--rw date?                  yang:date-and-time
       |  +--rw feed-type              enumeration
       |  +--rw feed-server?           inet:ipv4-address
       |  +--rw feed-priority?         uint16
       +--rw custom-list* [custom-list-id]
       |  +--rw custom-list-id         uint16
       |  +--rw name?                  string
       |  +--rw date?                  yang:date-and-time
       |  +--rw list-type              enumeration
       |  +--rw list-property          enumeration
       |  +--rw list-content?          string
       +--rw malware-scan-group* [malware-scan-group-id]
       |  +--rw malware-scan-group-id  uint16
       |  +--rw name?                  string
       |  +--rw date?                  yang:date-and-time
       |  +--rw signature-server?      inet:ipv4-address
       |  +--rw file-types?            string
       |  +--rw malware-signatures?    string
       +--rw event-map-group* [event-map-group-id]
          +--rw event-map-group-id     uint16
          +--rw name?                  string
          +--rw date?                  yang:date-and-time
          +--rw security-events?       string
          +--rw threat-map?            string
      
   

Figure 4: Policy Instance Example for VoIP/VoLTE Security Services

Appendix C. Policy Instance YANG Example for VoIP/VoLTE Security Services

The following YANG data model is a policy instance for VoIP/VoLTE security services. The policy-calendar can act as a scheduler to set the start time and end time to block malicious calls which use suspicious IDs, or calls from other countries.


<CODE BEGINS> file "ietf-i2nsf-cf-interface-voip.yang"

  module ietf-policy-voip {
  namespace
    "urn:ietf:params:xml:ns:yang:ietf-policy-voip";
  prefix
    "cf-interface";
      
  import ietf-yang-types{
    prefix yang;
  }

  import ietf-inet-types{
    prefix inet;
  }
  organization
    "IETF I2NSF (Interface to Network Security Functions) 
     Working Group";

  contact
    "WG Web: <http://tools.ietf.org/wg/i2nsf>
     WG List: <mailto:i2nsf@ietf.org>

     WG Chair: Adrian Farrel
     <mailto:Adrain@olddog.co.uk>

     WG Chair: Linda Dunbar
     <mailto:Linda.duhbar@huawei.com>

     Editor: Jaehoon Paul Jeong
     <mailto:pauljeong@skku.edu>";
        
  description
    "This module defines a YANG data module for consumer-facing 
     interface to security controller.";

  revision "2018-07-02"{
    description "sixth revision";
    reference
      "draft-kumar-i2nsf-client-facing-interface-im-04";
  }
  
  container policy-voip {
          description
            "This object is a policy instance to have
            complete information such as where and when
            a policy need to be applied.";
    list rule-voip {
          key "rule-voip-id";
          leaf rule-voip-id {
          type uint16;
          mandatory true;
          description
          "This is ID for rules.";
          }
          description
          "This is a container for rules.";
          leaf name {
            type string;
            description
              "This field idenfifies the name of this object.";
          }
          leaf date {
            type yang:date-and-time;
            description
              "Date this object was created or last 
              modified";
          }
        list event {
          key "event-id";
          description
          "This represents the security event of a
              policy-rule.";
          leaf event-id {
            type string;
            mandatory true;
            description
              "This represents the event-id.";
          }
          leaf name {
            type string;
            description
              "This field idenfifies the name of this object.";
          }
          leaf date {
            type yang:date-and-time;
            description
              "Date this object was created or last 
              modified";
          }
          leaf event-type {
            type string;
            description
              "This field identifies the event event type 
              .";
          }
          leaf Time-Information {
            type string;
            description
              "This field contains time calendar such as
             BEGIN-TIME and END-TIME for one time 
             enforcement or recurring time calendar for 
             periodic enforcement.";
          }
          leaf event-map-group {
            type leafref{
              path "/threat-feed/event-map-group/event-map-group-id";
          }
            description
            "This field contains security events or threat
            map in order to determine when a policy need 
            to be activated. This is a reference to
            Evnet-Map-Group.";
          }
          leaf enable {
            type boolean;
            description
              "This determines whether the condition
              matches the security event or not.";
          }
        }
        list condition {
          key "condition-id";
          description
          "This represents the condition of a
              policy-rule.";
          leaf condition-id {
            type string;
            description
              "This represents the condition-id.";
          }
          leaf source-caller {
            type leafref {
              path "/threat-feed/threat-feed/threat-feed-id";
            }
            description
              "This field identifies the source of
              the traffic. This could be reference to 
              either 'Policy Endpoint Group' or 
              'Threat-Feed' or 'Custom-List' if Security 
              Admin wants to specify the source; otherwise, 
              the default is to match all traffic.";
          }
          leaf destination-callee {
            type leafref {
              path "/threat-feed/custom-list/custom-list-id";
            }
            description
              "This field identifies the source of
              the traffic. This could be reference to 
              either 'Policy Endpoint Group' or 
              'Threat-Feed' or 'Custom-List' if Security 
              Admin wants to specify the source; otherwise, 
              the default is to match all traffic.";
          }
          leaf match {
            type boolean;
            description
              "This field identifies the match criteria used to
             evaluate whether the specified action need to be 
             taken or not.  This could be either a Policy-
             Endpoint-Group identifying a Application set or a 
             set of traffic rules.";
          }
          leaf match-direction {
            type string;
            description
              "This field identifies if the match criteria is
             to evaluated for both direction of the traffic or
             only in one direction with default of allowing in
             the other direction for stateful match conditions.
             This is optional and by default rule should apply 
             in both directions.";
          }
          leaf exception {
            type string;
            description
              "This field identifies the exception 
              consideration when a rule is evaluated for a 
              given communication.  This could be reference to 
              Policy-Endpoint-Group object or set of traffic 
              matching criteria.";
          }
        }
        list action {
          key "action-id";
          leaf action-id {
          type string;
          mandatory true;
          description
            "this represents the policy-action-id.";
          }
          description
            "This object represents actions that a 
            Security Admin wants to perform based on 
            a certain traffic class.";
          leaf name {
            type string;
            description
              "The name of the policy-action object.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "When the object was created or last 
              modified.";
          }
          leaf primary-action {
            type string;
            description
              "This field identifies the action when a rule
              is matched by NSF. The action could be one of
              'PERMIT', 'DENY', 'RATE-LIMIT', 'TRAFFIC-CLASS', 
              'AUTHENTICATE-SESSION', 'IPS, 'APP-FIREWALL', etc.";
          }
          leaf secondary-action {
            type string;
            description
              "This field identifies additional actions if
              a rule is matched. This could be one of 'LOG',
              'SYSLOG', 'SESSION-LOG', etc.";
          }
        }
        leaf precedence {
          type uint16;
            description
              "This field identifies the precedence
              assigned to this rule by Security Admin.
              This is helpful in conflict resolution 
              when two or more rules match a given 
              traffic class.";
        }
    }
    list owner {
          key "owner-id";
          leaf owner-id {
          type string;
          mandatory true;
          description
            "this represents the owner-id.";
          }
          description
            "This field defines the owner of this policy.
            Only the owner is authorized to modify the 
            contents of the policy.";
          leaf name {
            type string;
            description
              "The name of the owner.";
          }
          leaf date {
            type yang:date-and-time;
            description
              "When the object was created or last 
              modified.";
          }
    }
  }
  container threat-feed {
      description
      "this describes the list of threat-feed.";

        list threat-feed {
          key "threat-feed-id";
          leaf threat-feed-id {
          type uint16;
          mandatory true;
          description
            "This represents the threat-feed-id.";
          }
          description
            "This represents the threat feed within the 
            threat-prevention-list.";
          leaf name {
            type string;
            description
              "Name of the theat feed.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the threat-feed was created.";
          }

          leaf feed-type {
            type enumeration {
              enum unknown {
                description
                  "feed-type is unknown.";
              }
              enum ip-address {
                description
                  "feed-type is IP address.";
              }
              enum url {
                description
                  "feed-type is URL.";
              }
            }
            mandatory true; 
            description
              "This determined whether the feed-type is IP address 
              based or URL based.";
          }

          leaf feed-server {
            type inet:ipv4-address;
            description
              "this contains threat feed server information.";
          }

          leaf feed-priority {
            type uint16;
            description
              "this describes the priority of the threat from 
              0 to 5, where 0 means the threat is minimum and
              5 meaning the maximum.";
          }
      }

      list custom-list {
          key "custom-list-id";
          leaf custom-list-id {
          type uint16;
          description
          "this describes the custom-list-id.";
          }
          description
          "this describes the threat-prevention custom list.";
          leaf name {
            type string;
            description
              "Name of the custom-list.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the custom list was created.";
          }

          leaf list-type {
            type enumeration {
              enum unknown {
                description
                  "list-type is unknown.";
              }
              enum ip-address {
                description
                  "list-type is IP address.";
              }
              enum mac-address {
                description
                  "list-type is MAC address.";
              }
              enum url {
                description
                  "list-type is URL.";
              }
            }
            mandatory true; 
            description
              "This determined whether the feed-type is IP address 
              based or URL based.";
          }

         leaf list-property {
            type enumeration {
              enum unknown {
                description
                  "list-property is unknown.";
              }
              enum blacklist {
                description
                  "list-property is blacklist.";
              }
              enum whitelist {
                description
                  "list-property is whitelist.";
              }
            }
            mandatory true; 
            description
              "This determined whether the list-type is blacklist 
              or whitelist.";
          }

          leaf list-content {
            type string;
            description
              "This describes the contents of the custom-list.";
          }
      }

      list malware-scan-group {
          key "malware-scan-group-id";
          leaf malware-scan-group-id {
          type uint16;
          mandatory true;
          description
          "This is the malware-scan-group-id.";
          }
          description
          "This represents the malware-scan-group.";
          leaf name {
            type string;
            description
              "Name of the malware-scan-group.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the malware-scan-group was created.";
          }

          leaf signature-server {
            type inet:ipv4-address;
            description
              "This describes the signature server of the 
              malware-scan-group.";
          }
          
          leaf file-types {
            type string;
            description
              "This contains a list of file types needed to
              be scanned for the virus.";
          }

          leaf malware-signatures {
            type string;
            description
              "This contains a list of malware signatures or hash.";
          }
      }

      list event-map-group {
          key "event-map-group-id";
          leaf event-map-group-id {
          type uint16;
          mandatory true;
          description
          "This is the event-map-group-id.";
          }
          description
          "This represents the event map group.";
      
          leaf name {
            type string;
            description
              "Name of the event-map.";
          }

          leaf date {
            type yang:date-and-time;
            description
              "when the event-map was created.";
          }

          leaf security-events {
            type string;
            description
              "This contains a list of security events.";
          }

          leaf threat-map {
            type string;
            description
              "This contains a list of threat levels.";
          }
      }
    }
}
          
  
<CODE ENDS>
            

Figure 5: Policy Instance YANG Example for VoIP Security Services

Appendix D. Example XML output for VoIP service

In this section, we present an XML example for VoIP service. Here, we are going to drop calls commin from a country with an Ip from South Africa that is classified as malicious.


<?xml version="1.1" encoding="UTF-8"?>
<rpc message-id="1" xmlns="urn:ietf:params:xml:ns:restconf:base:1.0">
 <edit-config>
  <target>
   <running/>
  </target>
   <config>
    <i2nsf-cf-interface-voip-req nc:operation="create">
        <policy-voip>
            <rule-voip>
                <rule-voip-id>01</rule-voip-id>
                <rule-voip-name>voip-policy-example</rule-voip-name>
                <rule-voip-date>2017.10.25/20:30:32</rule-voip-date>
                <event>
                    <event-id>01</event-id>
                    <event-name>voip_call</event-name>
                    <event-date>2017.10.25/20:30:32</event-date>
                    <event-type>malicious</event-type>
                    <time-information>
                        <begin-time>22:00</begin-time>
                        <end-time>08:00</end-time>
                    </time-information>
                    <event-map-group>19</event-map-group>
                    <enable>True</enable>
                </event>
                <condition>
                    <condition-id>01</condition-id>
                    <source-caller>105.176.0.0</source-caller>
                    <destination-callee>192.168.171.35</destination-callee>
                    <match-direction>default</match-direction>
                    <exeption>00</exeption>
                </condition>
                <action>
                    <action-id>01</action-id>
                    <action-name>action-voip</action-name>
                    <action-date>2017.10.25/20:30:32</action-date>
                    <primary-action>DENY</primary-action>
                    <secondary-action>LOG</secondary-action>
                </action>
                <precedence>none</precedence>
              <owner>
                <owner-id>01</owner-id>
                <name>i2nsf-admin</name>
              </owner>
            </rule-voip>
        </policy-voip>
    </i2nsf-cf-interface-voip-req>
   </config>
 </edit-config>
</rpc>
       

Figure 6: An XML example for VoIP service

Authors' Addresses

Jaehoon Paul Jeong Department of Software Sungkyunkwan University 2066 Seobu-Ro, Jangan-Gu Suwon, Gyeonggi-Do 16419 Republic of Korea Phone: +82 31 299 4957 Fax: +82 31 290 7996 EMail: pauljeong@skku.edu URI: http://iotlab.skku.edu/people-jaehoon-jeong.php
Eunsoo Kim Department of Electrical and Computer Engineering Sungkyunkwan University 2066 Seobu-Ro, Jangan-Gu Suwon, Gyeonggi-Do 16419 Republic of Korea Phone: +82 31 299 4104 EMail: eskim86@skku.edu URI: http://seclab.skku.edu/people/eunsoo-kim/
Tae-Jin Ahn Korea Telecom 70 Yuseong-Ro, Yuseong-Gu Daejeon, 305-811 Republic of Korea Phone: +82 42 870 8409 EMail: taejin.ahn@kt.com
Rakesh Kumar Juniper Networks 1133 Innovation Way Sunnyvale, CA 94089 USA EMail: rkkumar@juniper.net
Susan Hares Huawei 7453 Hickory Hill Saline, MI 48176 USA Phone: +1-734-604-0332 EMail: shares@ndzh.com