Applicability of Interfaces to Network Security Functions to Network-Based Security Services
draft-ietf-i2nsf-applicability-01

Network Working Group                                           J. Jeong
Internet-Draft                                                   S. Hyun
Intended status: Informational                   Sungkyunkwan University
Expires: April 5, 2018                                            T. Ahn
                                                           Korea Telecom
                                                                S. Hares
                                                                  Huawei
                                                                D. Lopez
                                                          Telefonica I+D
                                                         October 2, 2017


 Applicability of Interfaces to Network Security Functions to Network-
                        Based Security Services
                   draft-ietf-i2nsf-applicability-00

Abstract

   This document describes the applicability of Interface to Network
   Security Functions (I2NSF) to network-based security services in
   Network Functions Virtualization (NFV) environments, such as
   firewall, deep packet inspection, or attack mitigation engines.

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
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   This Internet-Draft will expire on April 5, 2018.

Copyright Notice




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   Copyright (c) 2017 IETF Trust and the persons identified as the
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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Requirements Language  . . . . . . . . . . . . . . . . . . . .  3
   3.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   4.  I2NSF Framework  . . . . . . . . . . . . . . . . . . . . . . .  4
   5.  Use Cases  . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     5.1.  Firewall: Centralized Firewall System  . . . . . . . . . .  6
     5.2.  Deep Packet Inspection: Centralized VoIP/VoLTE
           Security System  . . . . . . . . . . . . . . . . . . . . .  7
     5.3.  Attack Mitigation: Centralized DDoS-attack Mitigation
           System . . . . . . . . . . . . . . . . . . . . . . . . . .  9
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   7.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 11
   8.  Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 11
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 12
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 12




















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1.  Introduction

   Interface to Network Security Functions (I2NSF) defined a framework
   and interfaces for interacting with Network Security Functions
   (NSFs).  The I2NSF framework allows heterogeneous NSFs developed by
   different security solution vendors to be used in the NFV environment
   by utilizing the capabilities of such products and the virtualization
   of security functions in the NFV platform.  In the I2NSF framework,
   each NSF initially registers the profile of its own capabilities into
   the system in order for themselves to be available in the system.  In
   addition, the Security Controller registers itself to the I2NSF user
   so that the user can request security services to the Security
   Controller.

   This document describes the applicability of I2NSF to network-based
   security services with use cases, such as firewall
   [opsawg-firewalls], Deep Packet Inspection (DPI), and Distributed
   Denial of Service (DDoS) attack mitigation.  We implemented the I2NSF
   framework based on SDN for these use cases, and the implementation
   successfully verified the effectiveness of the I2NSF framework.

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 terminology described in [RFC7149],
   [ITU-T.Y.3300], [ONF-OpenFlow], [ONF-SDN-Architecture],
   [ITU-T.X.1252], [ITU-T.X.800], [i2nsf-framework],
   [i2nsf-terminology], [consumer-facing-inf-im],
   [consumer-facing-inf-dm], [i2nsf-nsf-cap-im], [nsf-facing-inf-dm],
   [registration-inf-im], [registration-inf-dm], and
   [nsf-triggered-steering].  In addition, the following terms are
   defined below:

   o  Software-Defined Networking (SDN): A set of techniques that
      enables to directly program, orchestrate, control, and manage
      network resources, which facilitates the design, delivery and
      operation of network services in a dynamic and scalable manner
      [ITU-T.Y.3300].

   o  Firewall: A service function at the junction of two network
      segments that inspects every packet that attempts to cross the
      boundary.  It also rejects any packet that does not satisfy
      certain criteria for, for example, disallowed port numbers or IP



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      addresses.

   o  Centralized Firewall System: A centralized firewall that can
      establish and distribute policy rules into network resources for
      efficient firewall management.  These rules can be managed
      dynamically by a centralized server for firewall.  SDN can work as
      a network-based firewall system through a standard interface
      between an SDN switch and a firewall function as a vitual network
      function (VNF).

   o  Centralized VoIP Security System: A centralized security system
      that handles the security functions required for VoIP and VoLTE
      services.  SDN can work as a network-based security system through
      a standard interface between an SDN switch and a VoIP/VoLTE
      security function as a VNF.

   o  Centralized DDoS-attack Mitigation System: A centralized mitigator
      that can establish and distribute access control policy rules into
      network resources for efficient DDoS-attack mitigation.  These
      rules can be managed dynamically by a centralized server for DDoS-
      attack mitigation.  The SDN controller and switches can
      cooperatively work as a network-based firewall system through a
      standard interface between an SDN switch and a firewall function
      as a VNF running in the SDN controller.

4.  I2NSF Framework

   This section describes an I2NSF framework with SDN for I2NSF
   applicability and use cases, such as firewall, deep packet
   inspection, and DDoS-attack mitigation functions.

   Figure 1 shows an I2NSF framework [i2nsf-framework] with SDN networks
   to support network-based security services.  As shown in Figure 1,
   I2NSF User can use security functions by delivering their high-level
   security policies to the Security Controller via the Consumer-Facing
   Interface [consumer-facing-inf-im][consumer-facing-inf-dm].

   The Security Controller can translate the high-level security
   policies (received from an I2NSF User via the Consumer-Facing
   Interface) into low-level security policies for the corresponding
   NSFs.  These low-level security policies are sent to NSFs via the
   NSF-Facing Interface [i2nsf-nsf-cap-im][nsf-facing-inf-dm].

   The Security Controller requests NSFs to perform low-level security
   services via the NSF-Facing Interface.  The NSFs are enabled as
   Virtual Network Functions (VNFs) on top of virtual machines through
   Network Functions Virtualization (NFV) [ETSI-NFV].  The Security
   Controller also instructs the Switch Controller to perform their



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   required security services on switches under the supervision of
   Switch Controller (i.e., SDN Controller).  In addition, the Security
   Controller uses the I2NSF Registration Interface
   [registration-inf-im][registration-inf-dm] to communicate with
   Developer's Management System (called Developer's Mgmt System) for
   registering (or deregistering) the developer's NSFs into (or from)
   the NFV system using the I2NSF framework.

   The Consumer-Facing Interface between an I2NSF User and the Security
   Controller can be implemented using, for example, RESTCONF [RFC8040].
   Data models specified by YANG [RFC6020] describe high-level security
   policies to be specified by an I2NSF User.  The data model defined in
   [consumer-facing-inf-dm] can be used for the I2NSF Consumer-Facing
   Interface.

      +------------+
      | I2NSF User |
      +------------+
             ^
             | Consumer-Facing Interface
             v
   +-------------------+     Registration     +-----------------------+
   |Security Controller|<-------------------->|Developer's Mgmt System|
   +-------------------+       Interface      +-----------------------+
      ^     ^
      |     | NSF-Facing Interface
      |     v
      | +----------------+ +---------------+   +-----------------------+
      | |      NSF-1     |-|     NSF-2     |...|         NSF-n         |
      | |   (Firewall)   | |     (DPI)     |   |(DDoS-Attack Mitigator)|
      | +----------------+ +---------------+   +-----------------------+
      |
      | NSF-Facing Interface
      v                                              SDN Network
   +-------------------------------------------------------------------+
   |  +-----------------+                                              |
   |  |Switch Controller|                                              |
   |  +-----------------+                                              |
   |           ^                                                       |
   |           | SDN Southbound Interface                              |
   |           v                                                       |
   |      +--------+ +--------+      +--------+                        |
   |      |Switch 1|-|Switch 2|......|Switch m|                        |
   |      +--------+ +--------+      +--------+                        |
   +-------------------------------------------------------------------+

              Figure 1: An I2NSF Framework with SDN Networks




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   The NSF-Facing Interface between Security Controller and NSFs can be
   implemented using NETCONF [RFC6241].  YANG data models describe low-
   level security policies for the sake of NSFs, which are translated
   from the high-level security policies by the Security Controller.
   The data model defined in [nsf-facing-inf-dm] can be used for the
   I2NSF NSF-Facing Interface.

   The Registration Interface between the Security Controller and the
   Developer's Mgmt System can be implemented by RESTCONF [RFC8040].
   The data model defined in [registration-inf-dm] can be used for the
   I2NSF Registration Interface.

   Also, the I2NSF framework can enforce multiple chained NSFs for the
   low-level security policies by means of service function chaining
   (SFC) techniques for the I2NSF architecture described in
   [nsf-triggered-steering].

5.  Use Cases

   This section introduces three use cases for cloud-based security
   services: (i) firewall system, (ii) deep packet inspection system,
   and (iii) attack mitigation system.  [RFC8192]

5.1.  Firewall: Centralized Firewall System

   A centralized network firewall can manage each network resource and
   firewall rules can be managed flexibly by a centralized server for
   firewall (called Firewall).  The centralized network firewall
   controls each switch for the network resource management and the
   firewall rules can be added or deleted dynamically.

   The procedure of firewall operations in this system is as follows:

   1.  A switch forwards an unknown flow's packet to one of the Switch
       Controllers.

   2.  The Switch Controller forwards the unknown flow's packet to an
       appropriate security service application, such as the Firewall.

   3.  The Firewall analyzes, typically, the headers and contents of the
       packet.

   4.  If the Firewall regards the packet as a malicious one with a
       suspicious pattern, it reports the malicious packet to the Switch
       Controller.

   5.  The Switch Controller installs new rules (e.g., drop packets with
       the suspicious pattern) into underlying switches.



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   6.  The suspected packets are dropped by these switches.

   Existing SDN protocols can be used through standard interfaces
   between the firewall application and switches
   [RFC7149][ITU-T.Y.3300][ONF-OpenFlow] [ONF-SDN-Architecture].

   Legacy firewalls have some challenges such as the expensive cost,
   performance, management of access control, establishment of policy,
   and packet-based access mechanism.  The proposed framework can
   resolve the challenges through the above centralized firewall system
   based on SDN as follows:

   o  Cost: The cost of adding firewalls to network resources such as
      routers, gateways, and switches is substantial due to the reason
      that we need to add firewall on each network resource.  To solve
      this, each network resource can be managed centrally such that a
      single firewall is manipulated by a centralized server.

   o  Performance: The performance of firewalls is often slower than the
      link speed of network interfaces.  Every network resource for
      firewall needs to check firewall rules according to network
      conditions.  Firewalls can be adaptively deployed among network
      switches, depending on network conditions in the framework.

   o  The management of access control: Since there may be hundreds of
      network resources in a network, the dynamic management of access
      control for security services like firewall is a challenge.  In
      the framework, firewall rules can be dynamically added for new
      malware.

   o  The establishment of policy: Policy should be established for each
      network resource.  However, it is difficult to describe what flows
      are permitted or denied for firewall within a specific
      organization network under management.  Thus, a centralized view
      is helpful to determine security policies for such a network.

   o  Packet-based access mechanism: Packet-based access mechanism is
      not enough for firewall in practice since the basic unit of access
      control is usually users or applications.  Therefore, application
      level rules can be defined and added to the firewall system
      through the centralized server.

5.2.  Deep Packet Inspection: Centralized VoIP/VoLTE Security System

   A centralized VoIP/VoLTE security system can monitor each VoIP/VoLTE
   flow and manage VoIP/VoLTE security rules controlled by a centralized
   server for VoIP/VoLTE security service called VoIP Intrusion
   Prevention System (IPS).  The VoIP/VoLTE security system controls



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   each switch for the VoIP/VoLTE call flow management by manipulating
   the rules that can be added, deleted or modified dynamically.

   The procedure of VoIP/VoLTE security operations in this system is as
   follows:

   1.  A switch forwards an unknown call flow's signal packet (e.g., SIP
       packet) to the Switch Controller.  Also, if the packet belongs to
       a matched flow's packet related to SIP (called matched SIP
       packet), the Switch forwards the packet to the Switch Controller
       so that the packet can be checked by an NSF for VoIP (i.e., VoIP
       IPS) via the Switch Controller, which monitors the behavior of
       its SIP call.

   2.  The Switch Controller forwards the unknown flow's packet or the
       matched SIP packet to an appropriate security service function,
       such as VoIP IPS.

   3.  VoIP IPS analyzes the headers and contents of the signal packet,
       such as IP addresses, calling number, and session description
       headers [RFC4566].

   4.  If, for example, VoIP IPS regards the packet as a spoofed packet
       by hackers or a scanning packet searching for VoIP/VoLTE devices,
       it requests the Switch Controller to block that packet and the
       subsequent packets that have the same call-id.

   5.  The Switch Controller installs new rules (e.g., drop packets)
       into underlying switches.

   6.  The illegal packets are dropped by these switches.

   Existing SDN protocols can be used through standard interfaces
   between the VoIP IPS application and switches [RFC7149][ITU-T.Y.3300]
   [ONF-OpenFlow][ONF-SDN-Architecture].

   Legacy hardware based VoIP IPS has some challenges, such as
   provisioning time, the granularity of security, expensive cost, and
   the establishment of policy.  The I2NSF framework can resolve the
   challenges through the above centralized VoIP/VoLTE security system
   based on SDN as follows:

   o  Provisioning: The provisioning time of setting up a legacy VoIP
      IPS to network is substantial because it takes from some hours to
      some days.  By managing the network resources centrally, VoIP IPS
      can provide more agility in provisioning both virtual and physical
      network resources from a central location.




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   o  The granularity of security: The security rules of a legacy VoIP
      IPS are compounded considering the granularity of security.  The
      proposed framework can provide more granular security by
      centralizing security control into a switch controller.  The VoIP
      IPS can effectively manage security rules throughout the network.

   o  Cost: The cost of adding VoIP IPS to network resources, such as
      routers, gateways, and switches is substantial due to the reason
      that we need to add VoIP IPS on each network resource.  To solve
      this, each network resource can be managed centrally such that a
      single VoIP IPS is manipulated by a centralized server.

   o  The establishment of policy: Policy should be established for each
      network resource.  However, it is difficult to describe what flows
      are permitted or denied for VoIP IPS within a specific
      organization network under management.  Thus, a centralized view
      is helpful to determine security policies for such a network.

5.3.  Attack Mitigation: Centralized DDoS-attack Mitigation System

   A centralized DDoS-attack mitigation can manage each network resource
   and manipulate rules to each switch through a centralized server for
   DDoS-attack mitigation (called DDoS-attack Mitigator).  The
   centralized DDoS-attack mitigation system defends servers against
   DDoS attacks outside private network, that is, from public network.

   Servers are categorized into stateless servers (e.g., DNS servers)
   and stateful servers (e.g., web servers).  For DDoS-attack
   mitigation, traffic flows in switches are dynamically configured by
   traffic flow forwarding path management according to the category of
   servers [AVANT-GUARD].  Such a managenent should consider the load
   balance among the switches for the defense against DDoS attacks.

   The procedure of DDoS-attack mitigation operations in this system is
   as follows:

   1.  A Switch periodically reports an inter-arrival pattern of a
       flow's packets to one of the Switch Controllers.

   2.  The Switch Controller forwards the flow's inter-arrival pattern
       to an appropriate security service application, such as DDoS-
       attack Mitigator.

   3.  The DDoS-attack Mitigator analyzes the reported pattern for the
       flow.

   4.  If the DDoS-attack Mitigator regards the pattern as a DDoS
       attack, it computes a packet dropping probability corresponding



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       to suspiciousness level and reports this DDoS-attack flow to
       Switch Controller.

   5.  The Switch Controller installs new rules into switches (e.g.,
       forward packets with the suspicious inter-arrival pattern with a
       dropping probability).

   6.  The suspicious flow's packets are randomly dropped by switches
       with the dropping probability.

   For the above centralized DDoS-attack mitigation system, the existing
   SDN protocols can be used through standard interfaces between the
   DDoS-attack mitigator application and switches [RFC7149]
   [ITU-T.Y.3300][ONF-OpenFlow][ONF-SDN-Architecture].

   The centralized DDoS-attack mitigation system has challenges similar
   to the centralized firewall system.  The proposed framework can
   resolve the challenges through the above centralized DDoS-attack
   mitigation system based on SDN as follows:

   o  Cost: The cost of adding DDoS-attack mitigators to network
      resources such as routers, gateways, and switches is substantial
      due to the reason that we need to add DDoS-attack mitigator on
      each network resource.  To solve this, each network resource can
      be managed centrally such that a single DDoS-attack mitigator is
      manipulated by a centralized server.

   o  Performance: The performance of DDoS-attack mitigators is often
      slower than the link speed of network interfaces.  The checking of
      DDoS attacks may reduce the performance of the network interfaces.
      DDoS-attack mitigators can be adaptively deployed among network
      switches, depending on network conditions in the framework.

   o  The management of network resources: Since there may be hundreds
      of network resources in an administered network, the dynamic
      management of network resources for performance (e.g., load
      balancing) is a challenge for DDoS-attack mitigation.  In the
      framework, as dynamic network resource management, traffic flow
      forwarding path management can handle the load balancing of
      network switches [AVANT-GUARD].  With this management, the current
      and near-future workload can be spread among the network switches
      for DDoS-attack mitigation.  In addition, DDoS-attack mitigation
      rules can be dynamically added for new DDoS attacks.

   o  The establishment of policy: Policy should be established for each
      network resource.  However, it is difficult to describe what flows
      are permitted or denied for new DDoS-attacks (e.g., DNS reflection
      attack) within a specific organization network under management.



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      Thus, a centralized view is helpful to determine security policies
      for such a network.

   So far this document has described the procedure and impact of the
   three use cases for network-based security services using the I2NSF
   framework with SDN networks.  To support these use cases in the
   proposed data-driven security service framework, YANG data models
   described in [consumer-facing-inf-dm], [nsf-facing-inf-dm], and
   [registration-inf-dm] can be used as Consumer-Facing Interface, NSF-
   Facing Interface, and Registration Interface, respectively, along
   with RESTCONF [RFC8040] and NETCONF [RFC6241].

6.  Security Considerations

   The I2NSF framework with SDN networks in this document is derived
   from the I2NSF framework [i2nsf-framework], so the security
   considerations of the I2NSF framework should be included in this
   document.  Therefore, proper secure communication channels should be
   used the delivery of control or management messages among the
   components in the proposed framework.

   This document shares all the security issues of SDN that are
   specified in the "Security Considerations" section of [ITU-T.Y.3300].

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).

8.  Contributors

   I2NSF is a group effort.  I2NSF has had a number of contributing
   authors.  The following are considered co-authors:

   o  Hyoungshick Kim (Sungkyunkwan University)

   o  Jung-Soo Park (ETRI)

   o  Tae-Jin Ahn (Korea Telecom)

   o  Se-Hui Lee (Korea Telecom)

   o  Mohamed Boucadair (Orange)





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9.  References

9.1.  Normative References

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

   [i2nsf-framework]         Lopez, D., Lopez, E., Dunbar, L.,
                             Strassner, J., and R. Kumar, "Framework for
                             Interface to Network Security Functions",
                             draft-ietf-i2nsf-framework-07 (work in
                             progress), August 2017.

   [RFC6020]                 Bjorklund, M., "YANG - A Data Modeling
                             Language for the Network Configuration
                             Protocol (NETCONF)", RFC 6020,
                             October 2010.

   [RFC6241]                 Enns, R., Bjorklund, M., Schoenwaelder, J.,
                             and A. Bierman, "Network Configuration
                             Protocol (NETCONF)", RFC 6241, June 2011.

   [RFC8040]                 Bierman, A., Bjorklund, M., and K. Watsen,
                             "RESTCONF Protocol", RFC 8040,
                             January 2017.

9.2.  Informative References

   [consumer-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", draft-kumar-i2nsf-
                             client-facing-interface-im-03 (work in
                             progress), July 2017.

   [consumer-facing-inf-dm]  Jeong, J., Kim, E., Ahn, T., Kumar, R., and
                             S. Hares, "I2NSF Consumer-Facing Interface
                             YANG Data Model", draft-jeong-i2nsf-
                             consumer-facing-interface-dm-04 (work in
                             progress), October 2017.

   [i2nsf-nsf-cap-im]        Xia, L., Strassner, J., Basile, C., and D.
                             Lopez, "Information Model of NSFs
                             Capabilities",
                             draft-ietf-i2nsf-capability-00 (work in
                             progress), September 2017.




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   [nsf-facing-inf-dm]       Kim, J., Jeong, J., Park, J., Hares, S.,
                             and L. Xia, "I2NSF Network Security
                             Functions-Facing Interface YANG Data
                             Model", draft-kim-i2nsf-nsf-facing-
                             interface-data-model-03 (work in progress),
                             October 2017.

   [registration-inf-im]     Hyun, S., Jeong, J., Woo, S., Yeo, Y., and
                             J. Park, "I2NSF Registration Interface
                             Information Model", draft-hyun-i2nsf-
                             registration-interface-im-02 (work in
                             progress), July 2017.

   [registration-inf-dm]     Hyun, S., Jeong, J., Yeo, Y., Woo, S., and
                             J. Park, "I2NSF Registration Interface YANG
                             Data Model",
                             draft-hyun-i2nsf-registration-dm-01 (work
                             in progress), July 2017.

   [nsf-triggered-steering]  Hyun, S., Jeong, J., Park, J., and S.
                             Hares, "Service Function Chaining-Enabled
                             I2NSF Architecture",
                             draft-hyun-i2nsf-nsf-triggered-steering-03
                             (work in progress), July 2017.

   [RFC7149]                 Boucadair, M. and C. Jacquenet, "Software-
                             Defined Networking: A Perspective from
                             within a Service Provider Environment",
                             RFC 7149, March 2014.

   [ITU-T.Y.3300]            Recommendation ITU-T Y.3300, "Framework of
                             Software-Defined Networking", June 2014.

   [ONF-OpenFlow]            ONF, "OpenFlow Switch Specification
                             (Version 1.4.0)", October 2013.

   [ONF-SDN-Architecture]    ONF, "SDN Architecture", June 2014.

   [ITU-T.X.1252]            Recommendation ITU-T X.1252, "Baseline
                             Identity Management Terms and Definitions",
                             April 2010.

   [ITU-T.X.800]             Recommendation ITU-T X.800, "Security
                             Architecture for Open Systems
                             Interconnection for  CCITT Applications",
                             March 1991.

   [AVANT-GUARD]             Shin, S., Yegneswaran, V., Porras, P., and



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                             G. Gu, "AVANT-GUARD: Scalable and Vigilant
                             Switch Flow Management in Software-Defined
                             Networks", ACM CCS, November 2013.

   [ETSI-NFV]                ETSI GS NFV 002 V1.1.1, "Network Functions
                             Virtualisation (NFV); Architectural
                             Framework", October 2013.

   [RFC4566]                 Handley, M., Jacobson, V., and C. Perkins,
                             "SDP: Session Description Protocol",
                             RFC 4566, July 2006.

   [i2nsf-terminology]       Hares, S., Strassner, J., Lopez, D., Xia,
                             L., and H. Birkholz, "Interface to Network
                             Security Functions (I2NSF) Terminology",
                             draft-ietf-i2nsf-terminology-04 (work in
                             progress), July 2017.

   [opsawg-firewalls]        Baker, F. and P. Hoffman, "On Firewalls in
                             Internet Security",
                             draft-ietf-opsawg-firewalls-01 (work in
                             progress), October 2012.

   [RFC8192]                 Hares, S., Lopez, D., Zarny, M., Jacquenet,
                             C., Kumar, R., and J. Jeong, "Interface to
                             Network Security Functions (I2NSF): Problem
                             Statement and Use Cases", RFC 8192,
                             July 2017.

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









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   Sangwon Hyun
   Department of Software
   Sungkyunkwan University
   2066 Seobu-Ro, Jangan-Gu
   Suwon, Gyeonggi-Do  16419
   Republic of Korea

   Phone: +82 31 290 7222
   Fax:   +82 31 299 6673
   EMail: swhyun77@skku.edu
   URI:   http://imtl.skku.ac.kr/


   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


   Susan Hares
   Huawei
   7453 Hickory Hill
   Saline, MI  48176
   USA

   Phone: +1-734-604-0332
   EMail: shares@ndzh.com


   Diego R. Lopez
   Telefonica I+D
   Jose Manuel Lara, 9
   Seville,   41013
   Spain

   Phone: +34 682 051 091
   EMail: diego.r.lopez@telefonica.com










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