[VNFRQTS] break up larger rst files into toxtree

Broke all chapter files up so they follow the same patter

Change-Id: I8a2152b92f0568cf4858615054bb66fabf0ea343
Issue-ID: VNFRQTS-253
Signed-off-by: stark, steven <ss820f@att.com>

7 files changed, 1418 insertions, 0 deletions

diff --git a/docs/Chapter4/Design.rst b/docs/Chapter4/Design.rst
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+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+VNF Design
+----------
+
+Services are composed of VNFs and common components and are designed to
+be agnostic of the location to leverage capacity where it exists in the
+Network Cloud. VNFs can be instantiated in any location that meets the
+performance and latency requirements of the service.
+
+A key design principle for virtualizing services is decomposition of
+network functions using NFV concepts into granular VNFs. This enables
+instantiating and customizing only essential functions as needed for the
+service, thereby making service delivery more nimble. It provides
+flexibility of sizing and scaling and also provides flexibility with
+packaging and deploying VNFs as needed for the service. It enables
+grouping functions in a common cloud data center to minimize
+inter-component latency. The VNFs should be designed with a goal of
+being modular and reusable to enable using best-in-breed vendors.
+
+Section 5.a VNF Design in *VNF Guidelines* describes
+the overall guidelines for designing VNFs from VNF Components (VNFCs).
+Below are more detailed requirements for composing VNFs.
+
+VNF Design Requirements
+
+* R-58421 The VNF **SHOULD** be decomposed into granular re-usable VNFCs.
+* R-82223 The VNF **MUST** be decomposed if the functions have
+  significantly different scaling characteristics (e.g., signaling
+  versus media functions, control versus data plane functions).
+* R-16496 The VNF **MUST** enable instantiating only the functionality that
+  is needed for the decomposed VNF (e.g., if transcoding is not needed it
+  should not be instantiated).
+* R-02360 The VNFC **MUST** be designed as a standalone, executable process.
+* R-34484 The VNF **SHOULD** create a single component VNF for VNFCs
+  that can be used by other VNFs.
+* R-23035 The VNF **MUST** be designed to scale horizontally (more
+  instances of a VNF or VNFC) and not vertically (moving the existing
+  instances to larger VMs or increasing the resources within a VM)
+  to achieve effective utilization of cloud resources.
+* R-30650 The VNF **MUST** utilize cloud provided infrastructure and
+  VNFs (e.g., virtualized Local Load Balancer) as part of the VNF so
+  that the cloud can manage and provide a consistent service resiliency
+  and methods across all VNF's.
+* R-12709 The VNFC **SHOULD** be independently deployed, configured,
+  upgraded, scaled, monitored, and administered by ONAP.
+* R-37692 The VNFC **MUST** provide API versioning to allow for
+  independent upgrades of VNFC.
+* R-86585 The VNFC **SHOULD** minimize the use of state within
+  a VNFC to facilitate the movement of traffic from one instance
+  to another.
+* R-65134 The VNF **SHOULD** maintain state in a geographically
+  redundant datastore that may, in fact, be its own VNFC.
+* R-75850 The VNF **SHOULD** decouple persistent data from the VNFC
+  and keep it in its own datastore that can be reached by all instances
+  of the VNFC requiring the data.
+* R-88199 The VNF **MUST** utilize a persistent datastore service that
+  can meet the data performance/latency requirements. (For example:
+  Datastore service could be a VNFC in VNF or a DBaaS in the Cloud
+  execution environment)
+* R-99656 The VNF **MUST** NOT terminate stable sessions if a VNFC
+  instance fails.
+* R-84473 The VNF **MUST** enable DPDK in the guest OS for VNF’s requiring
+  high packets/sec performance.  High packet throughput is defined as greater
+  than 500K packets/sec.
+* R-54430 The VNF **MUST** use the NCSP’s supported library and compute
+  flavor that supports DPDK to optimize network efficiency if using DPDK. [1]_
+* R-18864 The VNF **MUST** NOT use technologies that bypass virtualization
+  layers (such as SR-IOV) unless approved by the NCSP (e.g., if necessary
+  to meet functional or performance requirements).
+* R-64768 The VNF **MUST** limit the size of application data packets
+  to no larger than 9000 bytes for SDN network-based tunneling when
+  guest data packets are transported between tunnel endpoints that
+  support guest logical networks.
+* R-74481 The VNF **MUST** NOT require the use of a dynamic routing
+  protocol unless necessary to meet functional requirements.
+
+
+.. [1]
+   Refer to NCSP’s Network Cloud specification
diff --git a/docs/Chapter4/Develop-Steps.rst b/docs/Chapter4/Develop-Steps.rst
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+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+
+VNF Develop Steps
+-----------------
+
+Aid to help the VNF provider to fasten the integration with the GVNFM, the
+ONAP provides the VNF SDK tools, and the documents. In this charter,
+the develop steps for VNF providers will be introduced.
+
+First, using the VNF SDK tools to design the VNF with TOSCA model and
+output the VNF TOSCA package. The VNF package can be validated, and
+tested.
+
+Second, the VNF provider should provide the VNF Rest API to integrate with
+the GVNFM if needed. The VNF Rest API is aligned to the ETSI IFA
+document.
+
+Third, the TOSCA model supports the HPA feature.
+
+Note:
+
+1. The scripts to extend capacity to satisfy some special requirements.
+   In the R2, the scripts is not implemented fully, and will be provided
+   in the next release.
+
+2. The monitoring and scale policy also be provide the next release.
diff --git a/docs/Chapter4/Devops.rst b/docs/Chapter4/Devops.rst
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+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+VNF Devops
+---------------------
+
+This section includes guidelines for VNF providers to ensure that a Network
+Cloud Service Provider’s operations personnel have a common and
+consistent way to support VNFs and VNFCs.
+
+NCSPs may elect to support standard images to enable compliance with
+security, audit, regulatory and other needs. As part of the overall VNF
+software bundle, VNF suppliers using standard images would typically
+provide the NCSP with an install package consistent with the default OS
+package manager (e.g. aptitude for Ubuntu, yum for Redhat/CentOS).
+
+Section 5.a DevOps in *VNF Guidelines* describes
+the DevOps guidelines for VNFs.
+
+DevOps Requirements
+
+* R-46960 NCSPs **MAY** operate a limited set of Guest OS and CPU
+  architectures and families, virtual machines, etc.
+* R-23475 VNFCs **SHOULD** be agnostic to the details of the Network Cloud
+  (such as hardware, host OS, Hypervisor or container technology) and must run
+  on the Network Cloud with acknowledgement to the paradigm that the Network
+  Cloud will continue to rapidly evolve and the underlying components of
+  the platform will change regularly.
+* R-33846 The VNF **MUST** install the NCSP required software on Guest OS
+  images when not using the NCSP provided Guest OS images. [1]_
+* R-09467 The VNF **MUST**  utilize only NCSP standard compute flavors. [1]_
+* R-02997 The VNF **MUST** preserve their persistent data. Running VMs
+  will not be backed up in the Network Cloud infrastructure.
+* R-29760 The VNFC **MUST** be installed on non-root file systems,
+  unless software is specifically included with the operating system
+  distribution of the guest image.
+* R-20860 The VNF **MUST** be agnostic to the underlying infrastructure
+  (such as hardware, host OS, Hypervisor), any requirements should be
+  provided as specification to be fulfilled by any hardware.
+* R-89800 The VNF **MUST NOT** require Hypervisor-level customization
+  from the cloud provider.
+* R-86758 The VNF **SHOULD** provide an automated test suite to validate
+  every new version of the software on the target environment(s). The tests
+  should be of sufficient granularity to independently test various
+  representative VNF use cases throughout its lifecycle. Operations might
+  choose to invoke these tests either on a scheduled basis or on demand to
+  support various operations functions including test, turn-up and
+  troubleshooting.
+* R-39650 The VNF **SHOULD** provide the ability to test incremental
+  growth of the VNF.
+* R-14853 The VNF **MUST** respond to a "move traffic" [2]_ command
+  against a specific VNFC, moving all existing session elsewhere with
+  minimal disruption if a VNF provides a load balancing function across
+  multiple instances of its VNFCs. Note: Individual VNF performance
+  aspects (e.g., move duration or disruption scope) may require further
+  constraints.
+* R-06327 The VNF **MUST** respond to a "drain VNFC" [2]_ command against
+  a specific VNFC, preventing new session from reaching the targeted VNFC,
+  with no disruption to active sessions on the impacted VNFC, if a VNF
+  provides a load balancing function across multiple instances of its VNFCs.
+  This is used to support scenarios such as proactive maintenance with no
+  user impact.
+* R-64713 The VNF **SHOULD** support a software promotion methodology
+  from dev/test -> pre-prod -> production in software, development &
+  testing and operations.
+
+
+.. [1]
+   Refer to NCSP’s Network Cloud specification
+
+.. [2]
+   Not currently supported in ONAP release 1
+
diff --git a/docs/Chapter4/Modularity.rst b/docs/Chapter4/Modularity.rst
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+++ b/docs/Chapter4/Modularity.rst
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+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+
+VNF Modularity
+--------------
+
+ONAP Heat Orchestration Templates: Overview
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+ONAP supports a modular Heat Orchestration Template design pattern,
+referred to as *VNF Modularity.*
+
+ONAP VNF Modularity Overview
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+With VNF Modularity, a single VNF may be composed from one or more Heat
+Orchestration Templates, each of which represents a subset of the
+overall VNF. These component parts are referred to as “\ *VNF
+Modules*\ ”. During orchestration, these modules are deployed
+incrementally to create the complete VNF.
+
+A modular Heat Orchestration Template can be either one of the following
+types:
+
+1. Base Module
+
+2. Incremental Module
+
+3. Cinder Volume Module
+
+* R-37028 The VNF **MUST** be composed of one “base” module.
+* R-41215 The VNF **MAY** have zero to many “incremental” modules.
+* R-20974 The VNF **MUST** deploy the base module first, prior to
+  the incremental modules.
+
+ONAP also supports the concept of an optional, independently deployed
+Cinder volume via a separate Heat Orchestration Templates, referred to
+as a Cinder Volume Module. This allows the volume to persist after a
+Virtual Machine (VM) (i.e., OS::Nova::Server) is deleted, allowing the
+volume to be reused on another instance (e.g., during a failover
+activity).
+
+* R-11200 The VNF **MUST** keep the scope of a Cinder volume module,
+  when it exists, to be 1:1 with the VNF Base Module or Incremental Module.
+
+* R-38474 The VNF **MUST** have a corresponding environment file for
+  a Base Module.
+* R-81725 The VNF **MUST** have a corresponding environment file for
+  an Incremental Module.
+* R-53433 The VNF **MUST** have a corresponding environment file for
+  a Cinder Volume Module.
+
+These concepts will be described in more detail throughout the document.
+This overview is provided to set the stage and help clarify the concepts
+that will be introduced.
+
+
+ONAP VNF Modularity
+^^^^^^^^^^^^^^^^^^^^^^
+
+ONAP supports a modular Heat Orchestration Template design pattern,
+referred to as *VNF Modularity.* With this approach, a single VNF may be
+composed from one or more Heat Orchestration Templates, each of which
+represents a subset of the overall VNF. These component parts are
+referred to as “\ *VNF Modules*\ ”. During orchestration, these modules
+are deployed incrementally to create the complete VNF.
+
+A modular Heat Orchestration Template can be either one of the following
+types:
+
+1. Base Module
+
+2. Incremental Module
+
+3. Cinder Volume Module
+
+A VNF must be composed of one “base” module and may be composed of zero
+to many “incremental” modules. The base module must be deployed first,
+prior to the incremental modules.
+
+ONAP also supports the concept of an optional, independently deployed
+Cinder volume via a separate Heat Orchestration Templates, referred to
+as a Cinder Volume Module. This allows the volume to persist after a VM
+(i.e., OS::Nova::Server) is deleted, allowing the volume to be reused on
+another instance (e.g., during a failover activity).
+
+The scope of a Cinder volume module, when it exists, must be 1:1 with a
+Base module or Incremental Module.
+
+A Base Module must have a corresponding environment file.
+
+An Incremental Module must have a corresponding environment file.
+
+A Cinder Volume Module must have a corresponding environment file.
+
+A VNF module (base, incremental, cinder) may support nested templates.
+
+A shared Heat Orchestration Template resource must be defined in the
+base module. A shared resource is a resource that that will be
+referenced by another resource that is defined in the Base Module and/or
+one or more incremental modules.
+
+When the shared resource needs to be referenced by a resource in an
+incremental module, the UUID of the shared resource must be exposed by
+declaring an ONAP Base Module Output Parameter.
+
+Note that a Cinder volume is *not* a shared resource. A volume template
+must correspond 1:1 with a base module or incremental module.
+
+An example of a shared resource is the resource
+OS::Neutron::SecurityGroup. Security groups are sets of IP filter rules
+that are applied to a VNF’s networking. The resource OS::Neutron::Port
+has a property security\_groups which provides the security groups
+associated with port. The value of parameter(s) associated with this
+property must be the UUIDs of the resource(s)
+OS::Neutron::SecurityGroup.
+
+*Note:* A Cinder volume is *not* considered a shared resource. A volume
+template must correspond 1:1 with a base template or add-on module
+template.
+
+Suggested Patterns for Modular VNFs
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+There are numerous variations of VNF modularity. Below are two suggested
+usage patterns.
+
+**Option 1: Modules per VNFC type**
+
+a. Base module contains only the shared resources.
+
+b. Group all VMs (e.g., VNFCs) of a given type (i.e. {vm-type}) into its
+   own incremental module. That is, the VNF has an incremental module
+   for each {vm-type}.
+
+c. For a given {vm-type} incremental module, the VNF may have
+
+   i.  One incremental module used for both initial turn up and re-used
+       for scaling. This approach is used when the number of VMs
+       instantiated will be the same for initial deployment and scaling.
+
+   ii. Two incremental modules, where one is used for initial turn up
+       and one is used for scaling. This approach is used when the
+       number of VMs instantiated will be different for initial
+       deployment and scaling.
+
+**Option 2: Base VNF with Incremental Growth Modules**
+
+a. Base module contains a complete initial VNF instance
+
+b. Incremental modules for incremental scaling units
+
+   i.  May contain VMs of multiple types in logical scaling combinations
+
+   ii. May be separated by VM type for multi-dimensional scaling
+
+With no growth units, Option 2 is equivalent to the “One Heat Template
+per VNF” model.
+
+Note that modularization of VNFs is not required. A single Heat
+Orchestration Template (a base module) may still define a complete VNF,
+which might be appropriate for smaller VNFs that do not have any scaling
+options.
+
+Modularity Rules
+^^^^^^^^^^^^^^^^^^^
+
+There are some rules to follow when building modular VNF templates:
+
+1. All VNFs must have one Base VNF Module (template) that must be the
+   first one deployed. The base template:
+
+   a. Must include all shared resources (e.g., private networks, server
+      groups, security groups)
+
+   b. Must expose all shared resources (by UUID) as “outputs” in its
+      associated Heat template (i.e., ONAP Base Module Output
+      Parameters)
+
+   c. May include initial set of VMs
+
+   d. May be operational as a stand-alone “minimum” configuration of the
+      VNF
+
+2. VNFs may have one or more incremental modules which:
+
+   a. Defines additional resources that can be added to an existing VNF
+
+   b. Must be complete Heat templates
+
+      i. i.e. not snippets to be incorporated into some larger template
+
+   c. Should define logical growth-units or sub-components of an overall
+      VNF
+
+   d. On creation, receives appropriate Base Module outputs as
+      parameters
+
+      i.  Provides access to all shared resources (by UUID)
+
+      ii. must not be dependent on other Add-On VNF Modules
+
+   e. Multiple instances of an incremental Module may be added to the
+      same VNF (e.g., incrementally grow a VNF by a fixed “add-on”
+      growth units)
+
+3. Each VNF Module (base or incremental) may have (optional) an
+   associated Cinder Volume Module (see Cinder Volume Templates)
+
+   a. Volume modules must correspond 1:1 with a base module or
+      incremental module
+
+   b. A Cinder volume may be embedded within the base module or
+      incremental module if persistence is not required
+
+4. Shared resource UUIDs are passed between the base module and
+   incremental modules via Heat Outputs Parameters (i.e., Base Module
+   Output Parameters)
+
+   a. The output parameter name in the base must match the parameter
+      name in the add-on module
+
+VNF Modularity Examples
+^^^^^^^^^^^^^^^^^^^^^^^
+
+*Example: Base Module creates SecurityGroup*
+
+A VNF has a base module, named base.yaml, that defines a
+OS::Neutron::SecurityGroup. The security group will be referenced by an
+OS::Neutron::Port resource in an incremental module, named
+INCREMENTAL\_MODULE.yaml. The base module defines a parameter in the out
+section named dns\_sec\_grp\_id. dns\_sec\_grp\_id is defined as a
+parameter in the incremental module. ONAP captures the UUID value of
+dns\_sec\_grp\_id from the base module output statement and provides the
+value to the incremental module.
+
+Note that the example below is not a complete Heat Orchestration
+Template. The {network-role} has been defined as oam to represent an oam
+network and the {vm-type} has been defined as dns.
+
+base\_MODULE.yaml
+
+.. code-block:: yaml
+
+ parameters:
+   . . .
+
+ resources:
+   DNS_SECURITY_GROUP:
+     type: OS::Neutron::SecurityGroup
+     properties:
+       description: vDNS security group
+       name:
+         str_replace:
+           template: VNF_NAME_sec_grp_DNS
+           params:
+             VMF_NAME: {get_param: vnf_name}
+       rules: [. . . . .
+
+   . . .
+
+ outputs:
+   dns_sec_grp_id:
+     description: UUID of DNS Resource SecurityGroup
+     value: { get_resource: DNS_SECURITY_GROUP }
+
+
+INCREMENTAL\_MODULE.yaml
+
+.. code-block:: yaml
+
+ parameters:
+   dns_sec_grp_id:
+     type: string
+     description: security group UUID
+   . . .
+
+ resources:
+   dns_oam_0_port:
+     type: OS::Neutron::Port
+     properties:
+       name:
+         str_replace:
+           template: VNF_NAME_dns_oam_port
+           params:
+             VNF_NAME: {get_param: vnf_name}
+       network: { get_param: oam_net_name }
+       fixed_ips: [{ "ip_address": { get_param: dns_oam_ip_0 }}]
+       security_groups: [{ get_param: dns_sec_grp_id }]
+
+
+*Examples: Base Module creates an internal network*
+
+A VNF has a base module, named base\_module.yaml, that creates an
+internal network. An incremental module, named incremental\_module.yaml,
+will create a VM that will connect to the internal network. The base
+module defines a parameter in the out section named int\_oam\_net\_id.
+int\_oam\_net\_id is defined as a parameter in the incremental module.
+ONAP captures the UUID value of int\_oam\_net\_id from the base module
+output statement and provides the value to the incremental module.
+
+Note that the example below is not a complete Heat Orchestration
+Template. The {network-role} has been defined as oam to represent an oam
+network and the {vm-type} has been defined as lb for load balancer.
+
+base.yaml
+
+.. code-block:: yaml
+
+ heat_template_version: 2013-05-23
+
+ resources:
+    int_oam_network:
+       type: OS::Neutron::Network
+       properties:
+          name: {… }
+          . . .
+ outputs:
+    int_oam_net_id:
+       value: {get_resource: int_oam_network }
+
+
+incremental.yaml
+
+.. code-block:: yaml
+
+ heat_template_version: 2013-05-23
+
+ parameters:
+    int_oam_net_id:
+       type: string
+       description: ID of shared private network from Base template
+    lb_name_0:
+       type: string
+       description: name for the add-on VM instance
+
+ Resources:
+    lb_server:
+       type: OS::Nova::Server
+       properties:
+          name: {get_param: lb_name_0}
+          networks:
+             - port: { get_resource: lb_port }
+          . . .
+
+    lb_port:
+       type: OS::Neutron::Port
+       properties:
+          network_id: { get_param: int_oam_net_id }
+ ...
diff --git a/docs/Chapter4/Resiliency.rst b/docs/Chapter4/Resiliency.rst
new file mode 100644
index 0000000..bf3e2e8
--- /dev/null
+++ b/docs/Chapter4/Resiliency.rst
@@ -0,0 +1,301 @@
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+VNF Resiliency
+-------------------------
+
+The VNF is responsible for meeting its resiliency goals and must factor
+in expected availability of the targeted virtualization environment.
+This is likely to be much lower than found in a traditional data center.
+Resiliency is defined as the ability of the VNF to respond to error
+conditions and continue to provide the service intended. A number of
+software resiliency dimensions have been identified as areas that should
+be addressed to increase resiliency. As VNFs are deployed into the
+Network Cloud, resiliency must be designed into the VNF software to
+provide high availability versus relying on the Network Cloud to achieve
+that end.
+
+Section 5.a Resiliency in *VNF Guidelines* describes
+the overall guidelines for designing VNFs to meet resiliency goals.
+Below are more detailed resiliency requirements for VNFs.
+
+All Layer Redundancy
+^^^^^^^^^^^^^^^^^^^^^^
+
+Design the VNF to be resilient to the failures of the underlying
+virtualized infrastructure (Network Cloud). VNF design considerations
+would include techniques such as multiple vLANs, multiple local and
+geographic instances, multiple local and geographic data replication,
+and virtualized services such as Load Balancers.
+
+
+All Layer Redundancy Requirements
+
+* R-52499 The VNF **MUST** meet their own resiliency goals and not rely
+  on the Network Cloud.
+* R-42207 The VNF **MUST** design resiliency into a VNF such that the
+  resiliency deployment model (e.g., active-active) can be chosen at
+  run-time.
+* R-03954 The VNF **MUST** survive any single points of failure within
+  the Network Cloud (e.g., virtual NIC, VM, disk failure).
+* R-89010 The VNF **MUST** survive any single points of software failure
+  internal to the VNF (e.g., in memory structures, JMS message queues).
+* R-67709 The VNF **MUST** be designed, built and packaged to enable
+  deployment across multiple fault zones (e.g., VNFCs deployed in
+  different servers, racks, OpenStack regions, geographies) so that
+  in the event of a planned/unplanned downtime of a fault zone, the
+  overall operation/throughput of the VNF is maintained.
+* R-35291 The VNF **MUST** support the ability to failover a VNFC
+  automatically to other geographically redundant sites if not
+  deployed active-active to increase the overall resiliency of the VNF.
+* R-36843 The VNF **MUST** support the ability of the VNFC to be deployable
+  in multi-zoned cloud sites to allow for site support in the event of cloud
+  zone failure or upgrades.
+* R-00098 The VNF **MUST NOT** impact the ability of the VNF to provide
+  service/function due to a single container restart.
+* R-79952 The VNF **SHOULD** support container snapshots if not for rebuild
+  and evacuate for rollback or back out mechanism.
+
+Minimize Cross Data-Center Traffic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Avoid performance-sapping data center-to-data center replication delay
+by applying techniques such as caching and persistent transaction paths
+- Eliminate replication delay impact between data centers by using a
+concept of stickiness (i.e., once a client is routed to data center "A",
+the client will stay with Data center “A” until the entire session is
+completed).
+
+Minimize Cross Data-Center Traffic Requirements
+
+* R-92935 The VNF **SHOULD** minimize the propagation of state information
+  across multiple data centers to avoid cross data center traffic.
+
+Application Resilient Error Handling
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Ensure an application communicating with a downstream peer is equipped
+to intelligently handle all error conditions. Make sure code can handle
+exceptions seamlessly - implement smart retry logic and implement
+multi-point entry (multiple data centers) for back-end system
+applications.
+
+Application Resilient Error Handling Requirements
+
+* R-26371 The VNF **MUST** detect communication failure for inter VNFC
+  instance and intra/inter VNF and re-establish communication
+  automatically to maintain the VNF without manual intervention to
+  provide service continuity.
+* R-18725 The VNF **MUST** handle the restart of a single VNFC instance
+  without requiring all VNFC instances to be restarted.
+* R-06668 The VNF **MUST** handle the start or restart of VNFC instances
+  in any order with each VNFC instance establishing or re-establishing
+  required connections or relationships with other VNFC instances and/or
+  VNFs required to perform the VNF function/role without requiring VNFC
+  instance(s) to be started/restarted in a particular order.
+* R-80070 The VNF **MUST** handle errors and exceptions so that they do
+  not interrupt processing of incoming VNF requests to maintain service
+  continuity (where the error is not directly impacting the software
+  handling the incoming request).
+* R-32695 The VNF **MUST** provide the ability to modify the number of
+  retries, the time between retries and the behavior/action taken after
+  the retries have been exhausted for exception handling to allow the
+  NCSP to control that behavior, where the interface and/or functional
+  specification allows for altering behaviour.
+* R-48356 The VNF **MUST** fully exploit exception handling to the extent
+  that resources (e.g., threads and memory) are released when no longer
+  needed regardless of programming language.
+* R-67918 The VNF **MUST** handle replication race conditions both locally
+  and geo-located in the event of a data base instance failure to maintain
+  service continuity.
+* R-36792 The VNF **MUST** automatically retry/resubmit failed requests
+  made by the software to its downstream system to increase the success rate.
+* R-70013 The VNF **MUST NOT** require any manual steps to get it ready for
+  service after a container rebuild.
+* R-65515 The VNF **MUST** provide a mechanism and tool to start VNF
+  containers (VMs) without impacting service or service quality assuming
+  another VNF in same or other geographical location is processing service
+  requests.
+* R-94978 The VNF **MUST** provide a mechanism and tool to perform a graceful
+  shutdown of all the containers (VMs) in the VNF without impacting service
+  or service quality assuming another VNF in same or other geographical
+  location can take over traffic and process service requests.
+
+
+System Resource Optimization
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Ensure an application is using appropriate system resources for the task
+at hand; for example, do not use network or IO operations inside
+critical sections, which could end up blocking other threads or
+processes or eating memory if they are unable to complete. Critical
+sections should only contain memory operation, and should not contain
+any network or IO operation.
+
+
+System Resource Optimization Requirements
+
+* R-22059 The VNF **MUST NOT** execute long running tasks (e.g., IO,
+  database, network operations, service calls) in a critical section
+  of code, so as to minimize blocking of other operations and increase
+  concurrent throughput.
+* R-63473 The VNF **MUST** automatically advertise newly scaled
+  components so there is no manual intervention required.
+* R-74712 The VNF **MUST** utilize FQDNs (and not IP address) for
+  both Service Chaining and scaling.
+* R-41159 The VNF **MUST** deliver any and all functionality from any
+  VNFC in the pool (where pooling is the most suitable solution). The
+  VNFC pool member should be transparent to the client. Upstream and
+  downstream clients should only recognize the function being performed,
+  not the member performing it.
+* R-85959 The VNF **SHOULD** automatically enable/disable added/removed
+  sub-components or component so there is no manual intervention required.
+* R-06885 The VNF **SHOULD** support the ability to scale down a VNFC pool
+  without jeopardizing active sessions. Ideally, an active session should
+  not be tied to any particular VNFC instance.
+* R-12538 The VNF **SHOULD** support load balancing and discovery
+  mechanisms in resource pools containing VNFC instances.
+* R-98989 The VNF **SHOULD** utilize resource pooling (threads,
+  connections, etc.) within the VNF application so that resources
+  are not being created and destroyed resulting in resource management
+  overhead.
+* R-55345 The VNF **SHOULD** use techniques such as “lazy loading” when
+  initialization includes loading catalogues and/or lists which can grow
+  over time, so that the VNF startup time does not grow at a rate
+  proportional to that of the list.
+* R-35532 The VNF **SHOULD** release and clear all shared assets (memory,
+  database operations, connections, locks, etc.) as soon as possible,
+  especially before long running sync and asynchronous operations, so as
+  to not prevent use of these assets by other entities.
+
+
+Application Configuration Management
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Leverage configuration management audit capability to drive conformity
+to develop gold configurations for technologies like Java, Python, etc.
+
+Application Configuration Management Requirements
+
+* R-77334 The VNF **MUST** allow configurations and configuration parameters
+  to be managed under version control to ensure consistent configuration
+  deployment, traceability and rollback.
+* R-99766 The VNF **MUST** allow configurations and configuration parameters
+  to be managed under version control to ensure the ability to rollback to
+  a known valid configuration.
+* R-73583 The VNF **MUST** allow changes of configuration parameters
+  to be consumed by the VNF without requiring the VNF or its sub-components
+  to be bounced so that the VNF availability is not effected.
+
+
+Intelligent Transaction Distribution & Management
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Leverage Intelligent Load Balancing and redundant components (hardware
+and modules) for all transactions, such that at any point in the
+transaction: front end, middleware, back end -- a failure in any one
+component does not result in a failure of the application or system;
+i.e., transactions will continue to flow, albeit at a possibly reduced
+capacity until the failed component restores itself. Create redundancy
+in all layers (software and hardware) at local and remote data centers;
+minimizing interdependencies of components (i.e. data replication,
+deploying non-related elements in the same container).
+
+Intelligent Transaction Distribution & Management Requirements
+
+* R-21558 The VNF **SHOULD** use intelligent routing by having knowledge
+  of multiple downstream/upstream endpoints that are exposed to it, to
+  ensure there is no dependency on external services (such as load balancers)
+  to switch to alternate endpoints.
+* R-08315 The VNF **SHOULD** use redundant connection pooling to connect
+  to any backend data source that can be switched between pools in an
+  automated/scripted fashion to ensure high availability of the connection
+  to the data source.
+* R-27995 The VNF **SHOULD** include control loop mechanisms to notify
+  the consumer of the VNF of their exceeding SLA thresholds so the consumer
+  is able to control its load against the VNF.
+
+Deployment Optimization
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Reduce opportunity for failure, by human or by machine, through smarter
+deployment practices and automation. This can include rolling code
+deployments, additional testing strategies, and smarter deployment
+automation (remove the human from the mix).
+
+Deployment Optimization Requirements
+
+* R-73364 The VNF **MUST** support at least two major versions of the
+  VNF software and/or sub-components to co-exist within production
+  environments at any time so that upgrades can be applied across
+  multiple systems in a staggered manner.
+* R-02454 The VNF **MUST** support the existence of multiple major/minor
+  versions of the VNF software and/or sub-components and interfaces that
+  support both forward and backward compatibility to be transparent to
+  the Service Provider usage.
+* R-57855 The VNF **MUST** support hitless staggered/rolling deployments
+  between its redundant instances to allow "soak-time/burn in/slow roll"
+  which can enable the support of low traffic loads to validate the
+  deployment prior to supporting full traffic loads.
+* R-64445 The VNF **MUST** support the ability of a requestor of the
+  service to determine the version (and therefore capabilities) of the
+  service so that Network Cloud Service Provider can understand the
+  capabilities of the service.
+* R-56793 The VNF **MUST** test for adherence to the defined performance
+  budgets at each layer, during each delivery cycle with delivered
+  results, so that the performance budget is measured and the code
+  is adjusted to meet performance budget.
+* R-77667 The VNF **MUST** test for adherence to the defined performance
+  budget at each layer, during each delivery cycle so that the performance
+  budget is measured and feedback is provided where the performance budget
+  is not met.
+* R-49308 The VNF **SHOULD** test for adherence to the defined resiliency
+  rating recommendation at each layer, during each delivery cycle with
+  delivered results, so that the resiliency rating is measured and the
+  code is adjusted to meet software resiliency requirements.
+* R-16039 The VNF **SHOULD** test for adherence to the defined
+  resiliency rating recommendation at each layer, during each
+  delivery cycle so that the resiliency rating is measured and
+  feedback is provided where software resiliency requirements are
+  not met.
+
+Monitoring & Dashboard
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Promote dashboarding as a tool to monitor and support the general
+operational health of a system. It is critical to the support of the
+implementation of many resiliency patterns essential to the maintenance
+of the system. It can help identify unusual conditions that might
+indicate failure or the potential for failure. This would contribute to
+improve Mean Time to Identify (MTTI), Mean Time to Repair (MTTR), and
+post-incident diagnostics.
+
+Monitoring & Dashboard Requirements
+
+* R-34957 The VNF **MUST** provide a method of metrics gathering for each
+  layer's performance to identify/document variances in the allocations so
+  they can be addressed.
+* R-49224 The VNF **MUST** provide unique traceability of a transaction
+  through its life cycle to ensure quick and efficient troubleshooting.
+* R-52870 The VNF **MUST** provide a method of metrics gathering
+  and analysis to evaluate the resiliency of the software from both
+  a granular as well as a holistic standpoint. This includes, but is
+  not limited to thread utilization, errors, timeouts, and retries.
+* R-92571 The VNF **MUST** provide operational instrumentation such as
+  logging, so as to facilitate quick resolution of issues with the VNF to
+  provide service continuity.
+* R-48917 The VNF **MUST** monitor for and alert on (both sender and
+  receiver) errant, running longer than expected and missing file transfers,
+  so as to minimize the impact due to file transfer errors.
+* R-28168 The VNF **SHOULD** use an appropriately configured logging
+  level that can be changed dynamically, so as to not cause performance
+  degradation of the VNF due to excessive logging.
+* R-87352 The VNF **SHOULD** utilize Cloud health checks, when available
+  from the Network Cloud, from inside the application through APIs to check
+  the network connectivity, dropped packets rate, injection, and auto failover
+  to alternate sites if needed.
+* R-16560 The VNF **SHOULD** conduct a resiliency impact assessment for all
+  inter/intra-connectivity points in the VNF to provide an overall resiliency
+  rating for the VNF to be incorporated into the software design and
+  development of the VNF.
diff --git a/docs/Chapter4/Security.rst b/docs/Chapter4/Security.rst
new file mode 100644
index 0000000..a0691ae
--- /dev/null
+++ b/docs/Chapter4/Security.rst
@@ -0,0 +1,563 @@
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+VNF Security
+----------------------
+
+The objective of this section is to provide the key security
+requirements that need to be met by VNFs. The security requirements are
+grouped into five areas as listed below. Other security areas will be
+addressed in future updates. These security requirements are applicable
+to all VNFs. Additional security requirements for specific types of VNFs
+will be applicable and are outside the scope of these general
+requirements.
+
+Section 5.a Security in *VNF Guidelines* outlines
+the five broad security areas for VNFs that are detailed in the
+following sections:
+
+-  **VNF General Security**: This section addresses general security
+   requirements for the VNFs that the VNF provider will need to address.
+
+-  **VNF Identity and Access Management**: This section addresses
+   security requirements with respect to Identity and Access Management
+   as these pertain to generic VNFs.
+
+-  **VNF API Security**: This section addresses the generic security
+   requirements associated with APIs. These requirements are applicable
+   to those VNFs that use standard APIs for communication and data
+   exchange.
+
+-  **VNF Security Analytics**: This section addresses the security
+   requirements associated with analytics for VNFs that deal with
+   monitoring, data collection and analysis.
+
+-  **VNF Data Protection**: This section addresses the security
+   requirements associated with data protection.
+
+VNF General Security Requirements
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+This section provides details on the VNF general security requirements
+on various security areas such as user access control, network security,
+ACLs, infrastructure security, and vulnerability management. These
+requirements cover topics associated with compliance, security patching,
+logging/accounting, authentication, encryption, role-based access
+control, least privilege access/authorization. The following security
+requirements need to be met by the solution in a virtual environment:
+
+General Security Requirements
+
+Integration and operation within a robust security environment is necessary
+and expected. The security architecture will include one or more of the
+following: IDAM (Identity and Access Management) for all system and
+applications access, Code scanning, network vulnerability scans, OS,
+Database and application patching, malware detection and cleaning,
+DDOS prevention, network security gateways (internal and external)
+operating at various layers, host and application based tools for
+security compliance validation, aggressive security patch application,
+tightly controlled software distribution and change control processes
+and other state of the art security solutions. The VNF is expected to
+function reliably within such an environment and the developer is
+expected to understand and accommodate such controls and can expected
+to supply responsive interoperability support and testing throughout
+the product’s lifecycle.
+
+* R-23740 The VNF **MUST** accommodate the security principle of
+  “least privilege” during development, implementation and operation.
+  The importance of “least privilege” cannot be overstated and must be
+  observed in all aspects of VNF development and not limited to security.
+  This is applicable to all sections of this document.
+* R-61354 The VNF **MUST** implement access control list for OA&M
+  services (e.g., restricting access to certain ports or applications).
+* R-85633 The VNF **MUST** implement Data Storage Encryption
+  (database/disk encryption) for Sensitive Personal Information (SPI)
+  and other subscriber identifiable data. Note: subscriber’s SPI/data
+  must be encrypted at rest, and other subscriber identifiable data
+  should be encrypted at rest. Other data protection requirements exist
+  and should be well understood by the developer.
+* R-92207 The VNF **SHOULD** implement a mechanism for automated and
+  frequent "system configuration (automated provisioning / closed loop)"
+  auditing.
+* R-23882 The VNF **SHOULD** be scanned using both network scanning
+  and application scanning security tools on all code, including underlying
+  OS and related configuration. Scan reports shall be provided. Remediation
+  roadmaps shall be made available for any findings.
+* R-46986 The VNF **SHOULD** have source code scanned using scanning
+  tools (e.g., Fortify) and provide reports.
+* R-55830 The VNF **MUST** distribute all production code from NCSP
+  internal sources only. No production code, libraries, OS images, etc.
+  shall be distributed from publically accessible depots.
+* R-99771 The VNF **MUST** provide all code/configuration files in a
+  "Locked down" or hardened state or with documented recommendations for
+  such hardening. All unnecessary services will be disabled. VNF provider
+  default credentials, community strings and other such artifacts will be
+  removed or disclosed so that they can be modified or removed during
+  provisioning.
+* R-19768 The VNF **SHOULD** support L3 VPNs that enable segregation of
+  traffic by application (dropping packets not belonging to the VPN) (i.e.,
+  AVPN, IPSec VPN for Internet routes).
+* R-33981 The VNF **SHOULD** interoperate with various access control
+  mechanisms for the Network Cloud execution environment (e.g.,
+  Hypervisors, containers).
+* R-40813 The VNF **SHOULD** support the use of virtual trusted platform
+  module, hypervisor security testing and standards scanning tools.
+* R-56904 The VNF **MUST** interoperate with the ONAP (SDN) Controller so that
+  it can dynamically modify the firewall rules, ACL rules, QoS rules, virtual
+  routing and forwarding rules.
+* R-26586 The VNF **SHOULD** support the ability to work with aliases
+  (e.g., gateways, proxies) to protect and encapsulate resources.
+* R-49956 The VNF **MUST** pass all access to applications (Bearer,
+  signaling and OA&M) through various security tools and platforms from
+  ACLs, stateful firewalls and application layer gateways depending on
+  manner of deployment. The application is expected to function (and in
+  some cases, interwork) with these security tools.
+* R-69649 The VNF **MUST** have all vulnerabilities patched as soon
+  as possible. Patching shall be controlled via change control process
+  with vulnerabilities disclosed along with mitigation recommendations.
+* R-78010 The VNF **MUST** use the NCSP’s IDAM API for Identification,
+  authentication and access control of customer or VNF application users.
+* R-42681 The VNF **MUST** use the NCSP’s IDAM API or comply with
+  the requirements if not using the NCSP’s IDAM API, for identification,
+  authentication and access control of OA&M and other system level
+  functions.
+* R-68589 The VNF **MUST**, if not using the NCSP’s IDAM API, support
+  User-IDs and passwords to uniquely identify the user/application. VNF
+  needs to have appropriate connectors to the Identity, Authentication
+  and Authorization systems that enables access at OS, Database and
+  Application levels as appropriate.
+* R-52085 The VNF **MUST**, if not using the NCSP’s IDAM API, provide
+  the ability to support Multi-Factor Authentication (e.g., 1st factor =
+  Software token on device (RSA SecureID); 2nd factor = User Name+Password,
+  etc.) for the users.
+* R-98391 The VNF **MUST**, if not using the NCSP’s IDAM API, support
+  Role-Based Access Control to permit/limit the user/application to
+  performing specific activities.
+* R-63217 The VNF **MUST**, if not using the NCSP’s IDAM API, support
+  logging via ONAP for a historical view of “who did what and when”.
+* R-62498 The VNF **MUST**, if not using the NCSP’s IDAM API, encrypt
+  OA&M access (e.g., SSH, SFTP).
+* R-79107 The VNF **MUST**, if not using the NCSP’s IDAM API, enforce
+  a configurable maximum number of Login attempts policy for the users.
+  VNF provider must comply with "terminate idle sessions" policy.
+  Interactive sessions must be terminated, or a secure, locking screensaver
+  must be activated requiring authentication, after a configurable period
+  of inactivity. The system-based inactivity timeout for the enterprise
+  identity and access management system must also be configurable.
+* R-35144 The VNF **MUST**, if not using the NCSP’s IDAM API, comply
+  with the NCSP’s credential management policy.
+* R-75041 The VNF **MUST**, if not using the NCSP’s IDAM API, expire
+  passwords at regular configurable intervals.
+* R-46908 The VNF **MUST**, if not using the NCSP’s IDAM API, comply
+  with "password complexity" policy. When passwords are used, they shall
+  be complex and shall at least meet the following password construction
+  requirements: (1) be a minimum configurable number of characters in
+  length, (2) include 3 of the 4 following types of characters:
+  upper-case alphabetic, lower-case alphabetic, numeric, and special,
+  (3) not be the same as the UserID with which they are associated or
+  other common strings as specified by the environment, (4) not contain
+  repeating or sequential characters or numbers, (5) not to use special
+  characters that may have command functions, and (6) new passwords must
+  not contain sequences of three or more characters from the previous
+  password.
+* R-39342 The VNF **MUST**, if not using the NCSP’s IDAM API, comply
+  with "password changes (includes default passwords)" policy. Products
+  will support password aging, syntax and other credential management
+  practices on a configurable basis.
+* R-40521 The VNF **MUST**, if not using the NCSP’s IDAM API, support
+  use of common third party authentication and authorization tools such
+  as TACACS+, RADIUS.
+* R-41994 The VNF **MUST**, if not using the NCSP’s IDAM API, comply
+  with "No Self-Signed Certificates" policy. Self-signed certificates
+  must be used for encryption only, using specified and approved
+  encryption protocols such as TLS 1.2 or higher or equivalent security
+  protocols such as IPSec, AES.
+* R-23135 The VNF **MUST**, if not using the NCSP’s IDAM API,
+  authenticate system to system communications where one system
+  accesses the resources of another system, and must never conceal
+  individual accountability.
+
+VNF Identity and Access Management Requirements
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following security requirements for logging, identity, and access
+management need to be met by the solution in a virtual environment:
+
+
+Identity and Access Management Requirements
+
+* R-95105 The VNF **MUST** host connectors for access to the application
+  layer.
+* R-45496 The VNF **MUST** host connectors for access to the OS
+  (Operating System) layer.
+* R-05470 The VNF **MUST** host connectors for access to the database layer.
+* R-99174 The VNF **MUST** comply with Individual Accountability
+  (each person must be assigned a unique ID) when persons or non-person
+  entities access VNFs.
+* R-42874 The VNF **MUST** comply with Least Privilege (no more
+  privilege than required to perform job functions) when persons
+  or non-person entities access VNFs.
+* R-71787 The VNF **MUST** comply with Segregation of Duties (access to a
+  single layer and no developer may access production without special
+  oversight) when persons or non-person entities access VNFs.
+* R-86261 The VNF **MUST NOT** allow VNF provider access to VNFs remotely.
+* R-49945 The VNF **MUST** authorize VNF provider access through a
+  client application API by the client application owner and the resource
+  owner of the VNF before provisioning authorization through Role Based
+  Access Control (RBAC), Attribute Based Access Control (ABAC), or other
+  policy based mechanism.
+* R-31751 The VNF **MUST** subject VNF provider access to privilege
+  reconciliation tools to prevent access creep and ensure correct
+  enforcement of access policies.
+* R-34552 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for OWASP Top 10.
+* R-29301 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Password Attacks.
+* R-72243 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Phishing / SMishing.
+* R-58998 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Malware (Key Logger).
+* R-14025 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Session Hijacking.
+* R-31412 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for XSS / CSRF.
+* R-51883 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Replay.
+* R-44032 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Man in the Middle (MITM).
+* R-58977 The VNF **MUST** provide or support the Identity and Access
+  Management (IDAM) based threat detection data for Eavesdropping.
+* R-24825 The VNF **MUST** provide Context awareness data (device,
+  location, time, etc.) and be able to integrate with threat detection system.
+* R-59391 The VNF provider **MUST**, where a VNF provider requires
+  the assumption of permissions, such as root or administrator, first
+  log in under their individual user login ID then switch to the other
+  higher level account; or where the individual user login is infeasible,
+  must login with an account with admin privileges in a way that
+  uniquely identifies the individual performing the function.
+* R-85028 The VNF **MUST** authenticate system to system access and
+  do not conceal a VNF provider user’s individual accountability for
+  transactions.
+* R-80335 The VNF **MUST** make visible a Warning Notice: A formal
+  statement of resource intent, i.e., a warning notice, upon initial
+  access to a VNF provider user who accesses private internal networks
+  or Company computer resources, e.g., upon initial logon to an internal
+  web site, system or application which requires authentication.
+* R-73541 The VNF **MUST** use access controls for VNFs and their
+  supporting computing systems at all times to restrict access to
+  authorized personnel only, e.g., least privilege. These controls
+  could include the use of system configuration or access control
+  software.
+* R-64503 The VNF **MUST** provide minimum privileges for initial
+  and default settings for new user accounts.
+* R-86835 The VNF **MUST** set the default settings for user access
+  to sensitive commands and data to deny authorization.
+* R-77157 The VNF **MUST** conform to approved request, workflow
+  authorization, and authorization provisioning requirements when
+  creating privileged users.
+* R-81147 The VNF **MUST** have greater restrictions for access and
+  execution, such as up to 3 factors of authentication and restricted
+  authorization, for commands affecting network services, such as
+  commands relating to VNFs.
+* R-49109 The VNF **MUST** encrypt TCP/IP--HTTPS (e.g., TLS v1.2)
+  transmission of data on internal and external networks.
+* R-39562 The VNF **MUST** disable unnecessary or vulnerable cgi-bin programs.
+* R-15671 The VNF **MUST NOT** provide public or unrestricted access
+  to any data without the permission of the data owner. All data
+  classification and access controls must be followed.
+* R-89753 The VNF **MUST NOT** install or use systems, tools or
+  utilities capable of capturing or logging data that was not created
+  by them or sent specifically to them in production, without
+  authorization of the VNF system owner.
+* R-19082 The VNF **MUST NOT** run security testing tools and
+  programs, e.g., password cracker, port scanners, hacking tools
+  in production, without authorization of the VNF system owner.
+* R-19790 The VNF **MUST NOT** include authentication credentials
+  in security audit logs, even if encrypted.
+* R-85419 The VNF **SHOULD** use REST APIs exposed to Client
+  Applications for the implementation of OAuth 2.0 Authorization
+  Code Grant and Client Credentials Grant, as the standard interface
+  for a VNF.
+* R-48080 The VNF **SHOULD** support SCEP (Simple Certificate
+  Enrollment Protocol).
+
+
+VNF API Security Requirements
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+This section covers API security requirements when these are used by the
+VNFs. Key security areas covered in API security are Access Control,
+Authentication, Passwords, PKI Authentication Alarming, Anomaly
+Detection, Lawful Intercept, Monitoring and Logging, Input Validation,
+Cryptography, Business continuity, Biometric Authentication,
+Identification, Confidentiality and Integrity, and Denial of Service.
+
+The solution in a virtual environment needs to meet the following API
+security requirements:
+
+
+API Requirements
+
+* R-37608 The VNF **MUST** provide a mechanism to restrict access based
+  on the attributes of the VNF and the attributes of the subject.
+* R-43884 The VNF **MUST** integrate with external authentication
+  and authorization services (e.g., IDAM).
+* R-25878 The VNF **MUST** use certificates issued from publicly
+  recognized Certificate Authorities (CA) for the authentication process
+  where PKI-based authentication is used.
+* R-19804 The VNF **MUST** validate the CA signature on the certificate,
+  ensure that the date is within the validity period of the certificate,
+  check the Certificate Revocation List (CRL), and recognize the identity
+  represented by the certificate where PKI-based authentication is used.
+* R-47204 The VNF **MUST** protect the confidentiality and integrity of
+  data at rest and in transit from unauthorized access and modification.
+* R-33488 The VNF **MUST** protect against all denial of service
+  attacks, both volumetric and non-volumetric, or integrate with external
+  denial of service protection tools.
+* R-21652 The VNF **MUST** implement the following input validation
+  control: Check the size (length) of all input. Do not permit an amount
+  of input so great that it would cause the VNF to fail. Where the input
+  may be a file, the VNF API must enforce a size limit.
+* R-54930 The VNF **MUST** implement the following input validation
+  control: Do not permit input that contains content or characters
+  inappropriate to the input expected by the design. Inappropriate input,
+  such as SQL insertions, may cause the system to execute undesirable
+  and unauthorized transactions against the database or allow other
+  inappropriate access to the internal network.
+* R-21210 The VNF **MUST** implement the following input validation
+  control: Validate that any input file has a correct and valid
+  Multipurpose Internet Mail Extensions (MIME) type. Input files
+  should be tested for spoofed MIME types.
+* R-23772 The VNF **MUST** validate input at all layers implementing VNF APIs.
+* R-87135 The VNF **MUST** comply with NIST standards and industry
+  best practices for all implementations of cryptography.
+* R-02137 The VNF **MUST** implement all monitoring and logging as
+  described in the Security Analytics section.
+* R-15659 The VNF **MUST** restrict changing the criticality level of
+  a system security alarm to administrator(s).
+* R-19367 The VNF **MUST** monitor API invocation patterns to detect
+  anomalous access patterns that may represent fraudulent access or
+  other types of attacks, or integrate with tools that implement anomaly
+  and abuse detection.
+* R-78066 The VNF **MUST** support requests for information from law
+  enforcement and government agencies.
+
+
+VNF Security Analytics Requirements
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+This section covers VNF security analytics requirements that are mostly
+applicable to security monitoring. The VNF Security Analytics cover the
+collection and analysis of data following key areas of security
+monitoring:
+
+-  Anti-virus software
+
+-  Logging
+
+-  Data capture
+
+-  Tasking
+
+-  DPI
+
+-  API based monitoring
+
+-  Detection and notification
+
+-  Resource exhaustion detection
+
+-  Proactive and scalable monitoring
+
+-  Mobility and guest VNF monitoring
+
+-  Closed loop monitoring
+
+-  Interfaces to management and orchestration
+
+-  Malformed packet detections
+
+-  Service chaining
+
+-  Dynamic security control
+
+-  Dynamic load balancing
+
+-  Connection attempts to inactive ports (malicious port scanning)
+
+The following requirements of security monitoring need to be met by the
+solution in a virtual environment.
+
+Security Analytics Requirements
+
+* R-48470 The VNF **MUST** support Real-time detection and
+  notification of security events.
+* R-22286 The VNF **MUST** support Integration functionality via
+  API/Syslog/SNMP to other functional modules in the network (e.g.,
+  PCRF, PCEF) that enable dynamic security control by blocking the
+  malicious traffic or malicious end users
+* R-32636 The VNF **MUST** support API-based monitoring to take care of
+  the scenarios where the control interfaces are not exposed, or are
+  optimized and proprietary in nature.
+* R-61648 The VNF **MUST** support event logging, formats, and delivery
+  tools to provide the required degree of event data to ONAP
+* R-22367 The VNF **MUST** support detection of malformed packets due to
+  software misconfiguration or software vulnerability.
+* R-31961 The VNF **MUST** support integrated DPI/monitoring functionality
+  as part of VNFs (e.g., PGW, MME).
+* R-20912 The VNF **MUST** support alternative monitoring capabilities
+  when VNFs do not expose data or control traffic or use proprietary and
+  optimized protocols for inter VNF communication.
+* R-73223 The VNF **MUST** support proactive monitoring to detect and
+  report the attacks on resources so that the VNFs and associated VMs can
+  be isolated, such as detection techniques for resource exhaustion, namely
+  OS resource attacks, CPU attacks, consumption of kernel memory, local
+  storage attacks.
+* R-58370 The VNF **MUST** coexist and operate normally with commercial
+  anti-virus software which shall produce alarms every time when there is a
+  security incident.
+* R-56920 The VNF **MUST** protect all security audit logs (including
+  API, OS and application-generated logs), security audit software, data,
+  and associated documentation from modification, or unauthorized viewing,
+  by standard OS access control mechanisms, by sending to a remote system,
+  or by encryption.
+* R-54520 The VNF **MUST** log successful and unsuccessful login attempts.
+* R-55478 The VNF **MUST** log logoffs.
+* R-08598 The VNF **MUST** log successful and unsuccessful changes to
+  a privilege level.
+* R-13344 The VNF **MUST** log starting and stopping of security
+  logging.
+* R-07617 The VNF **MUST** log creating, removing, or changing the
+  inherent privilege level of users.
+* R-94525 The VNF **MUST** log connections to a network listener of the
+  resource.
+* R-31614 The VNF **MUST** log the field “event type” in the security
+  audit logs.
+* R-97445 The VNF **MUST** log the field “date/time” in the security
+  audit logs.
+* R-25547 The VNF **MUST** log the field “protocol” in the security audit logs.
+* R-06413 The VNF **MUST** log the field “service or program used for
+  access” in the security audit logs.
+* R-15325 The VNF **MUST** log the field “success/failure” in the
+  security audit logs.
+* R-89474 The VNF **MUST** log the field “Login ID” in the security audit logs.
+* R-04982 The VNF **MUST NOT** include an authentication credential,
+  e.g., password, in the security audit logs, even if encrypted.
+* R-63330 The VNF **MUST** detect when the security audit log storage
+  medium is approaching capacity (configurable) and issue an alarm via
+  SMS or equivalent as to allow time for proper actions to be taken to
+  pre-empt loss of audit data.
+* R-41252 The VNF **MUST** support the capability of online storage of
+  security audit logs.
+* R-41825 The VNF **MUST** activate security alarms automatically when
+  the following event is detected: configurable number of consecutive
+  unsuccessful login attempts
+* R-43332 The VNF **MUST** activate security alarms automatically when
+  the following event is detected: successful modification of critical
+  system or application files
+* R-74958 The VNF **MUST** activate security alarms automatically when
+  the following event is detected: unsuccessful attempts to gain permissions
+  or assume the identity of another user
+* R-15884 The VNF **MUST** include the field “date” in the Security alarms
+  (where applicable and technically feasible).
+* R-23957 The VNF **MUST** include the field “time” in the Security alarms
+  (where applicable and technically feasible).
+* R-71842 The VNF **MUST** include the field “service or program used for
+  access” in the Security alarms (where applicable and technically feasible).
+* R-57617 The VNF **MUST** include the field “success/failure” in the
+  Security alarms (where applicable and technically feasible).
+* R-99730 The VNF **MUST** include the field “Login ID” in the Security
+  alarms (where applicable and technically feasible).
+* R-29705 The VNF **MUST** restrict changing the criticality level of a
+  system security alarm to administrator(s).
+* R-13627 The VNF **MUST** monitor API invocation patterns to detect
+  anomalous access patterns that may represent fraudulent access or other
+  types of attacks, or integrate with tools that implement anomaly and
+  abuse detection.
+* R-21819 The VNF **MUST** support requests for information from law
+  enforcement and government agencies.
+* R-56786 The VNF **MUST** implement “Closed Loop” automatic implementation
+  (without human intervention) for Known Threats with detection rate in low
+  false positives.
+* R-25094 The VNF **MUST** perform data capture for security functions.
+* R-04492 The VNF **MUST** generate security audit logs that must be sent
+  to Security Analytics Tools for analysis.
+* R-19219 The VNF **MUST** provide audit logs that include user ID, dates,
+  times for log-on and log-off, and terminal location at minimum.
+* R-30932 The VNF **MUST** provide security audit logs including records
+  of successful and rejected system access data and other resource access
+  attempts.
+* R-54816 The VNF **MUST** support the storage of security audit logs
+  for agreed period of time for forensic analysis.
+* R-57271 The VNF **MUST** provide the capability of generating security
+  audit logs by interacting with the operating system (OS) as appropriate.
+* R-84160 The VNF **MUST** have security logging for VNFs and their
+  OSs be active from initialization. Audit logging includes automatic
+  routines to maintain activity records and cleanup programs to ensure
+  the integrity of the audit/logging systems.
+
+VNF Data Protection Requirements
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+This section covers VNF data protection requirements that are mostly
+applicable to security monitoring.
+
+
+Data Protection Requirements
+
+* R-58964 The VNF **MUST** provide the capability to restrict read
+  and write access to data.
+* R-99112 The VNF **MUST** provide the capability to restrict access
+  to data to specific users.
+* R-83227 The VNF **MUST** Provide the capability to encrypt data in
+  transit on a physical or virtual network.
+* R-32641 The VNF **MUST** provide the capability to encrypt data on
+  non-volatile memory.
+* R-13151 The VNF **SHOULD** disable the paging of the data requiring
+  encryption, if possible, where the encryption of non-transient data is
+  required on a device for which the operating system performs paging to
+  virtual memory. If not possible to disable the paging of the data
+  requiring encryption, the virtual memory should be encrypted.
+* R-93860 The VNF **MUST** provide the capability to integrate with an
+  external encryption service.
+* R-73067 The VNF **MUST** use industry standard cryptographic algorithms
+  and standard modes of operations when implementing cryptography.
+* R-22645 The VNF **SHOULD** use commercial algorithms only when there
+  are no applicable governmental standards for specific cryptographic
+  functions, e.g., public key cryptography, message digests.
+* R-12467 The VNF **MUST NOT** use the SHA, DSS, MD5, SHA-1 and
+  Skipjack algorithms or other compromised encryption.
+* R-02170 The VNF **MUST** use, whenever possible, standard implementations
+  of security applications, protocols, and format, e.g., S/MIME, TLS, SSH,
+  IPSec, X.509 digital certificates for cryptographic implementations.
+  These implementations must be purchased from reputable vendors and must
+  not be developed in-house.
+* R-70933 The VNF **MUST** provide the ability to migrate to newer
+  versions of cryptographic algorithms and protocols with no impact.
+* R-44723 The VNF **MUST** use symmetric keys of at least 112 bits in length.
+* R-25401 The VNF **MUST** use asymmetric keys of at least 2048 bits in length.
+* R-95864 The VNF **MUST** use commercial tools that comply with X.509
+  standards and produce x.509 compliant keys for public/private key generation.
+* R-12110 The VNF **MUST NOT** use keys generated or derived from
+  predictable functions or values, e.g., values considered predictable
+  include user identity information, time of day, stored/transmitted data.
+* R-52060 The VNF **MUST** provide the capability to configure encryption
+  algorithms or devices so that they comply with the laws of the jurisdiction
+  in which there are plans to use data encryption.
+* R-69610 The VNF **MUST** provide the capability of using certificates
+  issued from a Certificate Authority not provided by the VNF provider.
+* R-83500 The VNF **MUST** provide the capability of allowing certificate
+  renewal and revocation.
+* R-29977 The VNF **MUST** provide the capability of testing the validity
+  of a digital certificate by validating the CA signature on the certificate.
+* R-24359 The VNF **MUST** provide the capability of testing the validity
+  of a digital certificate by validating the date the certificate is being
+  used is within the validity period for the certificate.
+* R-39604 The VNF **MUST** provide the capability of testing the
+  validity of a digital certificate by checking the Certificate Revocation
+  List (CRL) for the certificates of that type to ensure that the
+  certificate has not been revoked.
+* R-75343 The VNF **MUST** provide the capability of testing the
+  validity of a digital certificate by recognizing the identity represented
+  by the certificate — the "distinguished name".
diff --git a/docs/Chapter4/index.rst b/docs/Chapter4/index.rst
new file mode 100644
index 0000000..15fd8df
--- /dev/null
+++ b/docs/Chapter4/index.rst
@@ -0,0 +1,17 @@
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2017 AT&T Intellectual Property.  All rights reserved.
+
+
+VNF Development Requirements
+============================
+
+.. toctree::
+    :maxdepth: 2
+
+    Design
+    Resiliency
+    Security
+    Modularity
+    Devops
+    Develop-Steps