Registration Interface Information Model
draft-hyun-i2nsf-registration-interface-im-06

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Network Working Group                                            S. Hyun
Internet-Draft                                         Chosun University
Intended status: Standards Track                                J. Jeong
Expires: January 18, 2019                                         T. Roh
                                                                   S. Wi
                                                 Sungkyunkwan University
                                                                 J. Park
                                                                    ETRI
                                                           July 17, 2018

                Registration Interface Information Model
             draft-hyun-i2nsf-registration-interface-im-06

Abstract

   This document describes an information model for Interface to Network
   Security Functions (I2NSF) Registration Interface between Security
   Controller and Developer's Management System (DMS).  The information
   model is required to support NSF instance via the registration
   interface.  This document explains the procedures over I2NSF
   registration interface for these functionalities.  It also describes
   the detailed information which should be exchanged via I2NSF
   registration interface.

Status of This Memo

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Copyright Notice

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

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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Objectives  . . . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  Information Model . . . . . . . . . . . . . . . . . . . . . .   4
     5.1.  NSF Instance Managment Mechanism  . . . . . . . . . . . .   5
     5.2.  NSF Registration Mechanism  . . . . . . . . . . . . . . .   6
     5.3.  NSF Access Information  . . . . . . . . . . . . . . . . .   6
     5.4.  NSF Capability Information (Capabilities of an NSF
           instance) . . . . . . . . . . . . . . . . . . . . . . . .   7
       5.4.1.  Performance Capabilities  . . . . . . . . . . . . . .   7
     5.5.  Role-based Access Control List  . . . . . . . . . . . . .   8
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   7.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   9
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  10
   Appendix A.  Lifecycle Managmenet Mechanism . . . . . . . . . . .  12
   Appendix B.  Changes from draft-hyun-i2nsf-registration-
                interface-im-05  . . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12

1.  Introduction

   A number of virtual network security function instances typically
   exist in Interface to Network Security Functions (I2NSF) framework
   [RFC8329].  Since these NSF instances may have different security
   capabilities, it is important to register the security capabilities
   of each NSF instance into the security controller after they have
   been created.  In addition, it is required to instantiate NSFs of
   some required security capabilities on demand.  As an example, if
   additional security capabilities are required to meet the new
   security requirements that an I2NSF user requests, the security
   controller should be able to request the DMS to instantiate NSFs that
   have the required security capabilities.

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   This document describes the information model which is required for
   the registration interface between security controller and
   developer's management system to support registration and
   instantiation of NSFs.  It further describes the procedure based on
   the information model which should be performed by the security
   controller and the developer's management system via the registration
   interface.

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 [RFC2119].

3.  Terminology

   This document uses the terminology described in
   [i2nsf-terminology][capability-im][RFC8329] [nsf-triggered-steering].

   o  Network Security Function (NSF): A function that is responsible
      for specific treatment of received packets.  A Network Security
      Function can act at various layers of a protocol stack (e.g., at
      the network layer or other OSI layers).  Sample Network Security
      Service Functions are as follows: Firewall, Intrusion Prevention/
      Detection System (IPS/IDS), Deep Packet Inspection (DPI),
      Application Visibility and Control (AVC), network virus and
      malware scanning, sandbox, Data Loss Prevention (DLP), Distributed
      Denial of Service (DDoS) mitigation and TLS proxy
      [nsf-triggered-steering].

   o  Advanced Inspection/Action: As like the I2NSF information model
      for NSF-facing interface [capability-im], Advanced Inspection/
      Action means that a security function calls another security
      function for further inspection based on its own inspection result
      [nsf-triggered-steering].

   o  Network Security Function Profile (NSF Profile): NSF Profile
      specifies the security and performance capability of an NSF
      instance.  Each NSF instance has its own NSF Profile which
      describes the type of security service it can provide and its
      performance capabilinty. [nsf-triggered-steering].

4.  Objectives

   o  Registering NSF instances from Developer's Management System:
      Depending on system's security requirements, it may require some
      NSFs by default.  In this case, DMS creates these default NSF
      instances without the need of receiving requests from Security

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      Controller.  After creating them, DMS notifies Security Controller
      of those NSF instances via registration interface.

   o  Creating an NSF instance to serve another NSF's inspection
      request: In I2NSF framework, an NSF can trigger another type of
      NSF(s) for more advanced security inspection of the traffic.  In
      this case, the next NSF is determined by the current NSF's
      inspection result and client's policy.  However, if there is no
      available NSF instance to serve the former NSF's request, we
      should create an NSF instance by requesting Developer's Management
      System (DMS) through registration interface.

   o  Creating NSF instances required to enforce security policy rules
      from Client: In I2NSF framework, users decide which security
      service is necessary in the system.  If there is no NSF instances
      to enforce the client's security policy, then we should also
      create the required instances by requesting DMS via registration
      interface.

   o  Deleting unnecessary NSF instances: In I2NSF framework, users
      decide which security service is unnecessary in the system.  If
      there is unused NSF instances to enforce the client's security
      policy, then we should also delete the existing instances by
      requesting DMS via registration interface.

   o  Updating an NSF instances: After NSF instance is registered in
      I2NSF framework, capability of NSF instance can occur added and
      changed.  This situation should be recognized by the security
      controller of the I2NSF framework.  Therefore, if there is updated
      NSF instances, DMS notifies Security Controller of those NSF
      instances via registration interface.

5.  Information Model

   The I2NSF registration interface was only used for registering new
   NSF instances to Security Controller.  In this document, however, we
   extend its utilization to support on demand NSF instantiation/de-
   instantiation and describe the information that should be exchanged
   via the registration interface for the functionality.  Moreover, we
   also define the information model of NSF Profile because, for
   registration interface, NSF Profile (i.e., capabilities of an NSF)
   needs to be clarified so that the components of I2NSF framework can
   exchange the set of capabilities in a standardized manner.  This is
   typically done through the following process:

   1)  Security Controller first recognizes the set of capabilities
       (i.e., NSF Profile) or the signature of a specific NSF required
       or wasted in the current system.

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   2)  Developer's Management System (DMS) matches the recognized
       information to an NSF based on the information model definition.

   3)  Developer's Management System creates or eliminates NSFs matching
       with the above information.

   4)  Security Controller can then add/remove the corresponding NSF
       instance to/from its list of available NSF instances in the
       system.

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Registration Interface Information Model                          |
   |                                                                   |
   |       +-+-+-+-+-+-+-+-+-+-+-+-+-+       +-+-+-+-+-+-+-+-+-+-+-+   |
   |       |    Instance Management  |       |    Registration     |   |
   |       |         Sub-Model       |       |      Sub-Model      |   |
   |       +-+-+-+-+-+-+-+-+-+-+-+-+-+       +-+-+-+-+-+-+-+-+-+-+-+   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

            Figure 1: Registration Interface Information Model

   As illustrated in Figure 1, the information model for Registration
   Interface consists of two sub-models: instance management,
   registration sub-models.  The instance management functionality and
   the registration functionality use NSF Profile to achieve their
   goals.  In this context, NSF Profile is the capability objects that
   describe and/or prescribe inspection capability an NSF instance can
   provide.

5.1.  NSF Instance Managment Mechanism

   For the instance management of NSFs, Security Controller in I2NSF
   framework requires two types of requests: Instantiation Request and
   Deinstantiation Request.  Security Controller sends the request
   messages to DMS when required.  Once receiving the request, DMS
   conducts creating/eliminating the corresponding NSF instance and
   responds Security Controller with the results.

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            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+    +-+-+-+-+-+-+-+-+-+-+
            |  Instantiation/Re-instantiation |    | De-instantiation  |
            |             Request             |    |      Request      |
            +-+-+-+-+-+-+-+-+-^-+-+-+-+-+-+-+-+    +-+-+-+-+-^-+-+-+-+-+
                              |                              |
                              |                              |
                              |                              |
                              |                              |
                    +-+-+-+-+-+-+-+-+-+              +-+-+-+-+-+-+-+-+
                    |  NSF Capability |              |  NSF Access   |
                    |   Information   |              |  Information  |
                    +-+-+-+-+-+-+-+-+-+              +-+-+-+-+-+-+-+-+

            Figure 2: Overview of Instance Management Sub-Model

5.2.  NSF Registration Mechanism

   In order to register a new NSF instance, DMS should generate a
   Registration Message to Security Controller.  A Registration Message
   consists of an NSF Profile and an NSF Access Information.  The former
   describes the inspection capability of the new NSF instance and the
   latter is for enabling network access to the new instance from other
   components.  After this registration process, as explained in
   [capability-im], the I2NSF capability interface can conduct
   controlling and monitoring the new registered NSF instance.

                                 +-+-+-+-+-+-+-+-+
                                 |      NSF      |
                                 |  Registration |
                                 +-+-+-+-^-+-+-+-+
                                         |
                      +-------------------------------------+
                      |                  |                  |
                      |                  |                  |
             +-+-+-+-+-+-+-+-+-+  +-+-+-+-+-+-+-+  +-+-+-+-+-+-+-+-+-+
             |  NSF Capability |  | NSF Access  |  | NSF Rold-based  |
             |   Information   |  | Information |  |       ACL       |
             +-+-+-+-+-+-+-+-+-+  +-+-+-+-+-+-+-+  +-+-+-+-+-+-+-+-+-+

            Figure 3: Registration Mechanism Sub-Model Overview

5.3.  NSF Access Information

   NSF Access Information contains the followings that are required to
   communicate with an NSF: IPv4 address, IPv6 address, port number, and
   supported transport protocol(s) (e.g., Virtual Extensible LAN (VXLAN)
   [RFC 7348], Generic Protocol Extension for VXLAN (VXLAN-GPE)

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   [draft-ietf-nvo3-vxlan-gpe], Generic Route Encapsulation (GRE),
   Ethernet etc.).  In this document, NSF Access Information is used to
   identify a specific NSF instance (i.e.  NSF Access Information is the
   signature(unique identifier) of an NSF instance in the overall
   system).

5.4.  NSF Capability Information (Capabilities of an NSF instance)

   NSF Profile basically describes the inspection capabilities of an NSF
   instance.  In Figure 4, we show capability objects of an NSF
   instance.  Following the information model of NSF capabilities
   defiend in [capability-im], we share the same security capabilities:
   Network-Security Capabilities, Content-Security Capabilities, and
   Attack Mitigation Capabilities.  Also, NSF Profile additionally
   contains the performance capabilities and role-Based access control
   list (ACL) as shown in Figure 4.

                    +-+-+-+-+-+-+-+-+
                    |  Capability   |
                    |    Objects    |
                    +-+-+-+-^-+-+-+-+
                            |
                            |
               +---------------+-------+--------------+
               |                       |              |
               |                       |              |
       +-+-+-+-+-+-+-+-+-+     +-+-+-+-+-+-+-+-+-+    |
       |Network-Security |     |Content-Security |    |
       |   Capabilities  |     |   Capabilities  |    |
       +-+-+-+-+-+-+-+-+-+     +-+-+-+-+-+-+-+-+-+    |
                                                      |
               +-----------------------+--------------+
               |                       |
               |                       |
       +-+-+-+-+-+-+-+-+-+     +-+-+-+-+-+-+-+-+-+
       |   Performance   |     |Attack Mitigation|
       |   Capabilities  |     |   Capabilities  |
       +-+-+-+-+-+-+-+-+-+     +-+-+-+-+-+-+-+-+-+

                      Figure 4: NSF Profile Overview

5.4.1.  Performance Capabilities

   This information represents the processing capability of an NSF.
   This information can be used to determine whether the NSF is in
   congestion by comparing this with the workload that the NSF currently
   undergoes.  Moreover, this information can specify an available
   amount of each type of resources such as processing power which are

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   available on the NSF.  (The registration interface can control the
   usages and limitations of the created instance and make the
   appropriate request according to the status.)  As illustrated in
   Figure 5, this information consists of two items: Processing and
   Bandwidth.  Processing information describes the NSF's available
   processing power.  Bandwidth describes the information about
   available network amount in two cases, outbound, inbound.  This two
   information can be used for the NSF's instance request.

                            +-+-+-+-+-+-+-+-+-+
                            |   Performance   |
                            |   Capabilities  |
                            +-+-+-+-^-+-+-+-+-+
                                    |
                      +----------------------------+
                      |                            |
                      |                            |
              +-+-+-+-+-+-+-+-+            +-+-+-+-+-+-+-+
              |  Processing   |            |  Bandwidth  |
              +-+-+-+-+-+-+-+-+            +-+-+-+-+-+-+-+

                 Figure 5: Performance Capability Overview

5.5.  Role-based Access Control List

   This information specifies access policies of an NSF to determine
   whether to permit or deny the access of an entity to the NSF based on
   the role given to the entity.  Each NSF is associated with a role-
   based access control list (ACL) so that it can determine whether to
   permit or deny the access request from an entity.  Figure 6 and
   Figure 7 show the structure of the role-based ACL, which is composed
   of role-id, access-type, and permit/deny.  The role-id identifies
   roles of entities (e.g., administrator, developer etc.).  The access-
   type identifies the specific type of access requests such as NSF rule
   configuration/update and NSF monitoring.  Consequently, the role-
   based ACL in Figure 6 and Figure 7 specifies a set of access-types to
   be permitted and to be denied by each role-id.

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                              +-+-+-+-+-+-+-+-+
                              |   Role-based  |
                              |      ACL      |
                              +-+-+-+-+-+-+-+-+
                                      |
                    +-----------------------------------+
                    |                                   |
              +-+-+-+-+-+-+                       +-+-+-+-+-+-+
              | Role-id 1 |          ...          | Role-id N |
              +-+-+-+-+-+-+                       +-+-+-+-+-+-+

                 Figure 6: Role-based Access Control List

                              +-+-+-+-+-+-+-+-+
                              |   Role-id i   |
                              +-+-+-+-+-+-+-+-+
                                      |
                      +---------------------------------+
                      |                                 |
                +-+-+-+-+-+-+                     +-+-+-+-+-+-+
                |   Permit  |                     |   Deny    |
                +-+-+-+-+-+-+                     +-+-+-+-+-+-+
                      |                                 |
            +------------------+              +------------------+
            |                  |              |                  |
      +-+-+-+-+-+-+      +-+-+-+-+-+-+  +-+-+-+-+-+-+      +-+-+-+-+-+-+
      |access-type| ...  |access-type|  |access-type| ...  |access-type|
      |     p1    |      |     pn    |  |     d1    |      |     dn    |
      +-+-+-+-+-+-+      +-+-+-+-+-+-+  +-+-+-+-+-+-+      +-+-+-+-+-+-+

                         Figure 7: Role-id Subtree

6.  Security Considerations

   The information model of the registration interface is based on the
   I2NSF framework without any architectural changes.  Thus, this
   document shares the security considerations of the I2NSF framwork
   that are specified in [RFC8329] for the purpose of achieving secure
   communication between components in the proposed architecture.

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).

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   This document has greatly benefited from inputs by SangUk Woo and
   YunSuk Yeo.

8.  References

8.1.  Normative References

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

8.2.  Informative References

   [capability-im]
              Xia, L., Strassner, J., Basile, C., and D. Lopez,
              "Information Model of NSFs Capabilities", draft-ietf-
              i2nsf-capability-01 (work in progress), April 2018.

   [draft-ietf-nvo3-vxlan-gpe]
              Maino, Ed., F., Kreeger, Ed., L., and U. Elzur, Ed.,
              "Generic Protocol Extension for VXLAN", draft-ietf-nvo3-
              vxlan-gpe-06 (work in progress), April 2018.

   [i2nsf-hong-monitoring]
              Hong, D., Jeong, J., Kim, J., Hares, S., Xia, L., and H.
              Birkholz, "YANG Data Model for Monitoring I2NSF Network
              Security Functions", draft-hong-i2nsf-nsf-monitoring-data-
              model-03 (work in progress), March 2018.

   [i2nsf-nsf-monitoring]
              Xia, L., Zhang, D., Wu, Y., Kumar, R., Lohiya, A., and H.
              Birkholz, "An Information Model for the Monitoring of
              Network Security Functions(NSF)", draft-zhang-i2nsf-info-
              model-monitoring-06 (work in progress), May 2018.

   [i2nsf-terminology]
              Hares, S., Strassner, J., Lopez, D., Xia, L., and H.
              Birkholz, "Interface to Network Security Functions (I2NSF)
              Terminology", draft-ietf-i2nsf-terminology-05 (work in
              progress), January 2018.

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

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   [nsf-triggered-steering]
              Hyun, S., Jeong, J., Park, J., and S. Hares, "Service
              Function Chaining-Enabled I2NSF Architecture", draft-hyun-
              i2nsf-nsf-triggered-steering-05 (work in progress), March
              2018.

   [RFC8329]  Lopez, D., Lopez, E., Dunbar, L., Strassner, J., and R.
              Kumar, "Framework for Interface to Network Security
              Functions", RFC 8329, February 2018.

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Appendix A.  Lifecycle Managmenet Mechanism

   The [nfv-framework] in ETSI group defined the NSF architecture
   framework.  The NSF architecture framework provides VNF lifecycle
   management through the Ve-Vnfm interface.  The role of Ve-Vnfm is
   requesting for VNF lifecycle management, exchanging configuration
   information, and exchanging state information necessary for network
   service lifecycle management.

   For the lifecycle management of NSFs, DMSs receive the NSF capability
   information that obtained via monitoring NSF in the I2NSF system
   [i2nsf-hong-monitoring] and [i2nsf-nsf-monitoring] such as memory
   alarm, cpu alarm, disk alarm, hardware alarm, and interface alarm.
   So Ve-Vnfm interface and monitoring interface can interact for
   lifecycle management.

   This information can be additionally used for life-cycle management
   of NSF instances, and so the security controller can deliver the
   information to the DMSs via the registration interface.  As a result,
   registration interface can NSF capability management using
   [i2nsf-hong-monitoring], [i2nsf-nsf-monitoring], and [nfv-framework]

Appendix B.  Changes from draft-hyun-i2nsf-registration-interface-im-05

   The following changes are made from draft-hyun-i2nsf-registration-
   interface-im-05:

   o  Appendix A are clarified to discuss the use of the registration
      interface related to lifecycle management.

   o  Typos are corrected.

Authors' Addresses

   Sangwon Hyun
   Department of Computer Engineering
   Chosun University
   309, Pilmun-daero, Dong-gu
   Gwangju, Jeollanam-do  61452
   Republic of Korea

   EMail: shyun@chosun.ac.kr

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   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

   TaeKyun Roh
   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: tkroh0198@skku.edu
   URI:   http://imtl.skku.ac.kr/xe/index.php?mid=board_YoKq57

   SaRang Wi
   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: dnl9795@skku.edu
   URI:   http://imtl.skku.ac.kr/xe/index.php?mid=board_YoKq57

   Jung-Soo Park
   Electronics and Telecommunications Research Institute
   218 Gajeong-Ro, Yuseong-Gu
   Daejeon  305-700
   Republic of Korea

   Phone: +82 42 860 6514
   EMail: pjs@etri.re.kr

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