Network Working Group E. Lopez
Internet Draft Fortinet
Intended status: Informational D. Lopez
Expires: April 2016 Telefonica
L. Dunbar
Huawei
X. Zhuang
China Mobile
J. Parrott
BT
R Krishnan
Dell
S. Durbha
CableLabs
October 15, 2015
Framework for Interface to Network Security Functions
draft-merged-i2nsf-framework-03.txt
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Abstract
This document serves as the framework for detailed work items for
I2NSF. In the design of interfaces to allow for the provisioning of
network security functions (NSFs), a critical consideration is to
prevent the creation of implied constraints.
This document makes the recommendation that such interfaces be
designed from the paradigm of processing packets and flows on the
network. NSFs ultimately are packet-processing engines that inspect
packets traversing networks, either directly or in context to
sessions to which the packet is associated.
Table of Contents
1. Introduction...................................................3
2. Conventions used in this document..............................3
3. Interfaces to Flow-based NSFs..................................4
4. Reference Models in Managing NSFs..............................6
4.1. NSF Facing (Capability Layer) Interface...................7
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4.2. Client Facing (Service Layer) Interface...................7
4.3. Vendor Facing Interface...................................8
4.4. The network connecting the Security Controller and NSFs...8
4.5. Interface to vNSFs........................................9
5. Flow-based NSF Capability Characterization....................10
6. Structure of Rules to NSFs....................................13
6.1. Capability Layer Rules and Monitoring....................13
6.2. Service Layer Policy.....................................16
7. Capability Negotiation........................................19
8. Types of I2NSF clients........................................19
9. Manageability Considerations..................................20
10. Security Considerations......................................20
11. IANA Considerations..........................................20
12. References...................................................21
12.1. Normative References....................................21
12.2. Informative References..................................21
13. Acknowledgments..............................................22
1. Introduction
This document describes the framework for Interface to Network
Security Functions (I2NSF) and defines a reference model along with
functional components for I2NSF. It also describes how I2NSF
facilitates Software-defined network (SDN) and Network Function
Virtualization (NVF) control, while avoiding potential constraints
which could limit NSFs internal functions.
The I2NSF use cases ([I2NSF-ACCESS], [I2NSF-DC] and [I2NSF-Mobile])
call for standard interfaces for clients, e.g. applications,
application controllers, or users, to inform network what they are
willing to receive, when and how their specific data should be
delivered. And provide the standard interface for them to monitor
the security functions hosted and managed by service providers.
[I2NSF-Problem] describes the motivation and the problem space for
Interface to Network Security Functions.
2. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 [RFC2119].
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In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying RFC-2119 significance.
BSS: Business Support System
Controller: used interchangeably with Service Provider Security
Controller or management system throughout this
document.
FW: Firewall
IDS: Intrusion Detection System
IPS: Intrusion Protection System
NSF: Network Security Functions, defined by [I2NSF-Problem]
OSS: Operation Support System
vNSF: refers to NSF being instantiated on Virtual Machines.
3. Interfaces to Flow-based NSFs
The emergence of SDN and NFV has resulted in the need to create
application programming interfaces (APIs) in support of dynamic
requests from various applications or application controllers. Flow-
based NSFs [I2NSF-Problem] inspect and treat packets in the order as
they are received.
The Interface to Flow-based NSFs can be generally grouped into three
types:
1) Configuration - deals with the management and configuration of
the NSF device itself, such as port, supported protocols, and/or
addresses configurations. Configuration deals with attributes that
are don't change very much.
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2) Signaling - which represents logging and query functions between
the NSF and external systems. Signaling API functions may also be
well defined by other protocols such as SYSLOG, DOTS, etc.
3) Rules Provisioning - used to control the rules that govern how
packets are treated by the NSFs. To enable applications,
application controllers or clients to dynamically control
what/when/how traffic they want to receive, much of the I2NSF
efforts towards interface development will be in this area.
This draft proposes that a rule provisioning interface to NSFs can
be developed on a packet-based paradigm. While there are many
classifications of existing and emerging NSFs, a common trait shared
by them is in the processing of packets based on the content
(header/payload) and context (session state, authentication state,
etc) of received packets.
An important concept is the fact that attackers do not have
standards as to how to attack networks, so it is equally important
not to constrain NSF developers to offering a limited set of
security functions. Therefore, in constructing standards for rules
provisioning interfaces to NSFs, it is equally important to allow
support for vendor-specific functions, to allow the introduction of
NSFs that evolve to meet new threats. Proposed standards for rules
provisioning interfaces to NSFs should not:
- Narrowly define NSF categories, or their roles when implemented
within a network
- Attempt to impose functional requirements or constraints, either
directly or indirectly, upon NSF developers
- Be a limited lowest-common denominator approach, where interfaces
can only support a limited set of standardized functions, without
allowing for vendor-specific functions
- Be seen as endorsing a best-common-practice for the implementation
of NSFs
By using a packet-based approach to the design of such provisioning
interfaces, the goal is to create a workable interface to NSFs which
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aid in their integration within SDN/NFV environments, while avoiding
potential constraints which could limit their functional
capabilities.
Even though security functions come in variety of form factors and
have different features, provisioning to Flow-based NSFs can be
categorized by
- Subject - Match values based on packet data Packet header or
Packet payload, which can be one or more header fields or bits
in the packets, or the various combination of them;
- Object - Match values based on context, e.g. State, direction of
the traffic, time, geo-location, etc.,
- Action- Egress processing, such as Invoke signaling; Packet
forwarding and/or transformation; Possibility for SDN/NFV
integration, and
- Functional Profile - E.g. IPS:<Profile>, signature file, Anti-
virus file, URL filtering file, etc. Integrated and one-pass
checks on the content of packets.
The functional profile or signature file is one of the key
properties that determine the effectiveness of the NSF, and is
mostly vendor specific today.
4. Reference Models in Managing NSFs
This document only focuses on the framework of rules provisioning
and monitoring of the flow-based NSFs.
The following figure shows various interfaces for managing the
provisioning & monitoring aspects of flow-based NSFs.
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+------------------------------------------+
| Client or App Gateway |
| (e.g. Video conference Ctrl |
| Admin, OSS/BSS, or Service Orchestration)|
+-------+----------------------------------+
|
| Client Facing (service layer) Interface
+-----+---------------+
|Service Provider mgmt| +-------------+
| Security Controller | < -------- > | Vendor |
+---------------------+ Vendor Facing| Sys |
| Interface +-------------+
|
| NSF Facing (capability) Interface
|
+------------------------------------------------+
| |
| |
+------+ +------+ +------+ +------+
+ NSF-1+ ------- + NSF-n+ +NSF-1 + ----- +NSF-m + . . .
+------+ +------+ +------+ +------+
Vendor A Vendor B
Figure 1: Multiple Interfaces
4.1. NSF Facing (Capability Layer) Interface
This is the interface between the Service Provider's management
system (or Security Controller) and the NSFs that are selected to
enforce the desired network security. This interface is called
Capability Interface in the I2NSF context.
4.2. Client Facing (Service Layer) Interface
This interface is for clients or Application Controller to express
and monitor security policies for their specific flows. The client
facing interface is called Server Layer Interface in the I2NSF
context. The I2NSF Service Layer also allows clients to monitor
the client specific policies and execution status.
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A single client layer policy may need multiple NSFs or NSF
instantiations collectively together to achieve the enforcement.
4.3. Vendor Facing Interface
When service providers have multiple types of security functions
provided by different vendors, it is necessary to have an
interface for vendors to register their NSFs indicating their NSFs
capabilities.
The Registration Interface can be static or dynamic. When NSFs are
upgraded, vendors need to notify the service provider management
system or controller of the updated capabilities.
4.4. The network connecting the Security Controller and NSFs
Most likely, the NSFs are not directly attached to the Security
Controller; it is especially true when NSFs are distributed across
the network. The network that connects the Security Controller
with the NSFs can be the same network that carry the data traffic,
or can be a dedicated network for management purpose only. Either
case, packet loss could happen due to failure, congestion, or
other reasons.
Therefore, the transport mechanism used to carry the control
messages and monitoring information should provide reliable
message delivery. Transport redundancy mechanisms such as
Multipath TCP (MPTCP) [MPTCP] and the Stream Control Transmission
Protocol (SCTP) [RFC3286] will need to be evaluated for
applicability. Latency requirements for control message delivery
must also be evaluated.
The connection between Security Controller and NSFs could be:
- Closed environments where there is only one administrative
domain. More permissive access controls and lighter validation
is needed inside the domain because of the protected
environment.
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- Open environments where some NSFs (virtual or physical) can be
hosted in external administrative domains or reached via
external network domains. Then more restrictive security
controls are required over the I2NSF interface. The information
over the I2NSF interfaces must use trusted channels, such as
TLS, SASL, or the combination of the two.
Over the Open Environment, I2NSF needs to provide the identity
frameworks and federations models for authentication and
Authorization.
4.5. Interface to vNSFs
Even though there is no difference between virtual network
security functions (vNSF) and physical NSFs from policy
provisioning perspective, there are some unique characteristics in
interfacing to the vNSFs:
- There could be multiple instantiations of one single NSF being
distributed across network. When different instantiations are
visible to the Security Controller, different policies may be
applied to different instantiations of one single NSF.
- When multiple instantiations of one single NSF appear as one
single entity to the Security Controller, the policy
provisioning has to be sent to the NSF's sub-controller, which
in turn disseminate the polices to the corresponding
instantiations of the NSF, as shown in the Figure 2 below.
- Policies to one vNSF may need to be retrieved and move to
another vNSF of the same type when client flows are moved from
one vNSF to another.
- Multiple vNSFs may share the same physical platform
- There may be scenarios where multiple vNSFs collectively perform
the security policies needed.
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+------------------------+
| Security Controller |
+------------------------+
^ ^
| |
+-----------+ +------------+
| |
v v
+ - - - - - - - - - - - - - - - + + - - - - - - - - - - - - - - - +
| NSF-A +--------------+ | | NSF-B +--------------+ |
| |Sub Controller| | | |sub Controller| |
| +--------------+ | | +--------------+ |
| + - - - - - - - - - - - - - + | | + - - - - - - - - - - - - - + |
| |+---------+ +---------+| | | |+---------+ +---------+| |
| || NSF-A#1 | ... | NSF-A#n|| | | || NSF-B#1| ... | NSF-B#m|| |
| |+---------+ +---------+| | | |+---------+ +---------+| |
| | NSF-A cluster | | | | NSF-B cluster | |
| + - - - - - - - - - - - - - + | | + - - - - - - - - - - - - - + |
+ - - - - - - - - - - - - - - - + + - - - - - - - - - - - - - - - +
Figure 2: Cluster of NSF Instantiations Management
5. Flow-based NSF Capability Characterization
There are many types of flow-based NSFs. Firewall, IPS, and IDS are
the commonly deployed flow-based NSFs. However, the differences
among them are definitely blurring somewhat as technological
capacity increases, platforms are integrated, and the threat
landscape shifts. At their core:
. Firewall - A device or a function that analyzes packet headers and
enforces policy based on protocol type, source address,
destination address, source port, and/or destination port. Packets
that do not match policy are rejected.
. IDS (Intrusion Detection System) - A device or function that
analyzes whole packets, both header and payload, looking for known
events. When a known event is detected a log message is generated
detailing the event.
. IPS (Intrusion Prevention System) - A device or function that
analyzes whole packets, both header and payload, looking for known
events. When a known event is detected the packet is rejected.
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To prevent constraints on NSF vendors' creativity and innovation,
this document recommends the Flow-based NSF interfaces to be
designed from the paradigm of processing packets on the network.
Flow-based NSFs ultimately are packet-processing engines that
inspect packets traversing networks, either directly or in context
to sessions to which the packet is associated.
Flow-based NSFs differ in the depth of packet header or payload they
can inspect, the various session/context states they can maintain,
the specific profiles and the actions they can apply. An example of
session is "allowing outbound connection requests and only allowing
return traffic from the external network".
Accordingly, the NSF capabilities are characterized by the level of
packet processing and context that a NSF supports, the profiles and
the actions that the NSF can apply. The term "context" includes
session state, timer, and events.
Vendors can register their NSFs using the Subject-Object-Action-
Function categories described in Section 2, with detailed
specification of each category as shown in the table below:
+-----------------------------------------------------------+
| Subject Capability Index |
+---------------+-------------------------------------------+
| Layer 2 | Layer 2 header fields: |
| Header | Source/Destination/s-VID/c-VID/EtherType/.|
| | |
|---------------+-------------------------------------------+
| Layer 3 | Layer header fields: |
| | protocol |
| IPv4 Header | port |
| | src port |
| | dscp |
| | length |
| | flags |
| | ttl |
| | |
| IPv6 Header | |
| | addr |
| | protocol/nh |
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| | src port |
| | length |
| | traffic class |
| | hop limit |
| | flow label |
| | |
| TCP | Port |
| SCTP | syn |
| DCCP | ack |
| | fin |
| | rst |
| | ? psh |
| | ? urg |
| | ? window |
| | sockstress |
| | Note: bitmap could be used to |
| | represent all the fields |
| UDP | |
| | flood abuse |
| | fragment abuse |
| | Port |
| HTTP layer | |
| | | hash collision |
| | | http - get flood |
| | | http - post flood |
| | | http - random/invalid url |
| | | http - slowloris |
| | | http - slow read |
| | | http - r-u-dead-yet (rudy) |
| | | http - malformed request |
| | | http - xss |
| | | https - ssl session exhaustion |
+---------------+----------+--------------------------------+
| IETF PCP | Configurable |
| | Ports |
| | |
+---------------+-------------------------------------------+
| IETF TRAM | profile |
| | |
| | |
|---------------+-------------------------------------------+
Table 1: Subject Capability Index
+-----------------------------------------------------------+
| Object (context) matching Capability Index |
+---------------+-------------------------------------------+
| Session | Session state, |
| | bidirectional state |
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| | |
+---------------+-------------------------------------------+
| Time | time span |
| | days, minutes, seconds, |
| | Events |
+---------------+-------------------------------------------+
| Events | Event URL, variables |
+---------------+-------------------------------------------+
Table 2: Object Capability Index
+-----------------------------------------------------------+
| Action Capability Index |
+---------------+-------------------------------------------+
| Ingress port | SFC header termination , |
| | VxLAN header termination |
+---------------+-------------------------------------------+
| | Pass |
| Actions | Deny |
| | Mirror |
| | Simple Statistics: Count (X min; Day;..)|
| | Client specified Functions: URL |
+---------------+-------------------------------------------+
| Egress | Encap SFC, VxLAN, or other header |
+---------------+-------------------------------------------+
Table 3: Action Capability Index
+-----------------------------------------------------------+
| Functional profile Index |
+---------------+-------------------------------------------+
| Profile types | Name, type, or |
| Signature | Flexible Profile/signature URL |
| | Command for Controller to enable/disable |
| | |
+---------------+-------------------------------------------+
Table 4: Function Capability Index
6. Structure of Rules to NSFs
6.1. Capability Layer Rules and Monitoring
The Capability Layer is to express the explicit rules to individual
NSFs on how to treat packets and methods to monitor the execution
status of those functions.
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[ACL-MODEL] has defined rules for the Access Control List supported
by most routers/switches that forward packets based on packets' L2,
L3, or sometimes L4 headers. The actions for Access Control List
include Pass, Drop, or Redirect.
The functional profiles (or signatures) for NSFs are not present in
[ACL-MODEL] because the functional profiles are unique to specific
NSFs. Most vendors' IPS/IDS, and HoneyPot have their proprietary
functions/profiles. One of the goals of I2NSF is to have common
envelop format for exchanging or sharing profiles among different
organizations to achieve more effective protection against threats.
The "subject" of the I2NSF policies should not only include the
matching criteria specified by [ACL-MODEL] but also the L4-L7 fields
depending on the NSFs selected.
The I2NSF Capability Layer has to specify the "Object" (i.e. the
states/contexts surrounding the packets).
The I2NSF "actions" should extend the actions specified by [ACL-
MODEL] to include applying statistics functions that clients
provide.
The rules for Flow-Based NSF can be extended from the Policy Core
Information Model [RFC3060] and Policy Core Information Model
Extension [RFC3460] which are the bases for ITU-T X.1036 [ITU-T-
X1036], as shown below:
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+-------------------------+
| Capability Layer Rules |
+-------------------------+
| |
+---------+ +--------+ +---------+ |- Pass
|Compound | | | | Simple +-|- Deny
|Condition| | action | +--+ Actions| |- Mirror
+----+----+ +----+---+ | +---------+ |- Count
|<-------+ +---------------+ |- client func
+---+------+ | |
++---+-----+| | | +---------+
| simple || |Compound Operators: +--+ function|
|conditions|+ | Logical AND: && | Profile |
+--+-----+-+ | Logical OR: || +---------+
| | | Logical NOT: !
| +----+
+-----------+
+------+--+ +--+-----+ +---------+
| Subject | | Object | | Time |
| Match | | Match | +--+---------+
+-----+---+ +----+---+ | +---------+
| +-------------------+--+ States |
| | +---------+
+--+----------+----------+ | +---------+
+--+----+ +--+---+ +--+---+ +--+ Port |
|IPv4 | |IPv6 | | MAC | | +---------+
|Header | |Header| |Header| | *
+-------+ +------+ +------+ +--+ *
Figure 3: Structure of Capability Layer Rules
Capability layer also includes the policy monitoring of the
individual NSFs and fault management of the policy execution. In NFV
environment, policy consistency among multiple security function
instances is very critical because security policies are no longer
maintained by one central security devices, but instead are enforced
by multiple security functions instantiated at various locations.
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6.2. Service Layer Policy
This layer is for clients, applications or Application Controllers
to express & monitor the needed security policies for their specific
flows.
Some Customers may not have security skills. As such, they are not
able to express requirements or security policies that are precise
enough. Usually these customers are expressing expectations (that
can be viewed as loose security requirements). Customers may also
express guidelines such as which critical communications are to be
preserved during critical events, which hosts are to service even
during severe security attacks, etc. As the result, there could be
many depths or layers of Service Layer policies. Here are some
examples of more abstract service layer security Policies:
o Pass for Subscriber "xxx" with Port "y"
o enable basic parental control
o enable "school protection control"
o allow Internet traffic from 8:30 to 20:00 [time = 8:30-
20:00]
o scan email for malware detection [check type = malware]
protect traffic to corporate network with integrity and
confidentiality [protection type = integrity AND
confidentiality]
o remove tracking data from Facebook [website =
*.facebook.com]
o my son is allowed to access facebook from 18:30 to 20:00
One Service Layer Security Policy may need multiple security
functions at various locations to achieve the enforcement. Service
layer Security Policy may need to be updated by users or Application
Gateway when user's service requirements have been changed. [I2NSF-
Demo] describes an implementation of translating a set of service
layer policies to the Capability Layer instructions to NSFs.
I2NSF will first focus on simple service layer policies that are
modeled as closely as possible on the Capability Layer. The I2NSF
simple service layer should have similar structure as I2NSF
capability layer, however with more client oriented expression for
the subject, object, action, and function.
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There have been several industry initiatives to address network
policies, such as IETF Policy Core Information Model-PCIM [RFC3060,
RFC3460], OpenStack's Group-based Policy (GBP), and others. Since
I2NSF is not to tackle the general network service policies, but
instead I2NSF is to define a standard interface for
clients/applications to inform the Flow-based NSFs on the rules for
treating traffic traversing through, it is overkill to inherent the
entire policy structures designed for various network services.
However, the notion of Groups (or roles), Targets, Contexts (or
conditions), and actions do cover what are needed for
clients/applications to express the rules on how their flows to be
treated by the Flow-Based NSFs in networks. The goal is to have a
policy structure that can be mapped to the Capability layer's
Subject-Object-Action-Function" paradigm.
I2NSF can use PCIM (RFC3060 which the ITU-T X.1036 was based on) as
a starting point. However, RFC3060 was created for general network
policies, in some aspects more than what I2NSF needs, and in other
aspects needs extension. Especially need extension on the Policy
Context or condition (i.e. the directions, the time, and other
contextual events that govern the policies to NSFs).
The I2NSF simple service layer can have the following entities:
- Composite Groups or Roles (I2NSF-Role): This is a group of
users, applications, virtual networks, or traffic patterns to
which a service layer policy can be applied. An I2NSF-Role
may be mapped to a client virtual Subnet (i.e. with private
address prefix), a subnet with public address families,
specific applications, destinations, or any combination of
them with logical operators (Logical AND, OR, or NOT). An
I2NSF-Role can have one or more Policy Rule Sets.
- Target. This is used by the application client to establish
communications over the network. A Target is mapped to a
physical/logical ingress port, a set of destinations, or a
physical/logical egress port.
- Policy Rule Set. A Policy Rule Set is used to determine how
the traffic between a pair of I2NSF-Role and Target is to be
treated. A Policy Rule Set consists of one or more Policy
Rules.
- Policy Rule. A Policy Rule consists of a Policy Conditions
and a set of Actions to be applied to the traffic.
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- Policy Condition. Describes when a Policy Rule set is to be
applied. It can be expressed as a direction, a list of L4
ports, time range, or a protocol, etc.
- Policy Action: This is the action applied to the traffic that
matches the Conditions. An action may be a simple ACL action
(i.e. allow, deny, mirroring), applying a well known
statistics functions (e.g. X minutes count, Y hours court),
applying client specified functions (with URL provided), or
may refer to an ordered sequence of functions.
+---------+ +--------+ +-------+ |- Logical Port
| CTG |---->| Policy |<-----+Target +-|- Ingress Port
| | |Role Set| | | |- Egress Port
+----+----+ +----+---+ +-------+ |- *
|<-------+ +---------------+
+--+------+ | | +--------+Logical
+/---+-----+| | | +/-------+ |Combination:
| Simple || |Compound Operators: +--+ Policy | | AND/OR/NOT
| Group |+ | Logical AND: && | Rule | +
+--+-----+-/ | Logical OR: || +-+----+-/
| | | Logical NOT: ! / \
| +----+ +------+ +----------+
| |Action| -| Condition|
+----------+---------------+-- +---+--+ +--+-------+
+------+-+ +--+-----+ +---+-----+ | |-Direction
| App | |virtual | | Subnet | | |-timer
| Group | | Subnet | |host list| | |-L4 port
++-------+--+ +----+---+ +----+----+ | |-Protocol
|Client Grp| | | | |- *
+----------+ | | |
+-------------+--+------+-------+--- |
+--+----+ +--+---+ +--+---+ |-Allow
|IPv4 | |IPv6 | | MAC | |-Deny
|Header | |Header| |Header| |-count
+-------+ +------+ +------+ |-apply function list
|- *
Figure 4: Rule Structure for Simple Service Layer
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7. Capability Negotiation
When a NSF can't perform the desired provisioning due to resource
constraint, it has to inform the controller.
The protocol needed for this security function/capability
negotiation may be somewhat correlated to the dynamic service
parameter negotiation procedure [RFC7297]. The Connectivity
Provisioning Profile (CPP) template documented in RFC7297, even
though currently covering only Connectivity (but includes security
clauses such as isolation requirements, non-via nodes, etc.),
could be extended as a basis for the negotiation procedure.
Likewise, the companion Connectivity Provisioning Negotiation
Protocol (CPNP) could be a candidate to proceed with the
negotiation procedure.
The "security as a service" would be a typical example of the kind
of (CPP-based) negotiation procedures that could take place
between a corporate customer and a service provider. However, more
security specific parameters have to be considered.
8. Types of I2NSF clients
It is envisioned that I2NSF clients include:
- Application Gateway:
- For example, Video Conference Mgr/Controller needs to
dynamically inform network to allow or deny flows (some of
which are encrypted) based specific fields in the packets for
a certain time span. Otherwise, some flows can't go through
the NSFs (e.g. FW/IPS/IDS) in the network because the payload
is encrypted or packets' protocol codes are not recognized by
those NSFs.
- Security Administrators
- Enterprise
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- Operator Management System dynamically updates, monitors
and verifies the security policies to NSFs (by different
vendors) in a network.
- Third party system
- Security functions send requests for more sophisticated functions
upon detecting something suspicious, usually via a security
controller.
9. Manageability Considerations
Management of NSFs usually includes
- life cycle management and resource management of vNSFs
- configuration of devices, such as address configuration,
device internal attributes configuration, etc,
- signaling, and
- policy rules provisioning.
I2NSF will only focus on the policy rule provisioning part, i.e.
the last bullet listed above.
10. Security Considerations
Having a secure access to control and monitor NSFs is crucial for
hosted security service. Therefore, proper secure communication
channels have to be carefully specified for carrying the
controlling and monitoring information between the NSFs and their
management entity (or entities).
11. IANA Considerations
This document requires no IANA actions. RFC Editor: Please remove
this section before publication.
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12. References
12.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3060] Moore, B, et al, "Policy Core Information Model (PCIM)",
RFC 3060, Feb 2001.
[RFC3460] Moore, B. "Policy Core Information Model (PCIM)
Extensions", RFC3460, Jan 2003.
[RFC7297] Boucadair, M., "IP Connectivity Provisioning Profile",
RFC7297, April 2014.
12.2. Informative References
[I2NSF-ACCESS] A. Pastor, et al, "Access Use Cases for an Open OAM
Interface to Virtualized Security Services", <draft-
pastor-i2nsf-access-usecases-00>, Oct 2014.
[I2NSF-DC] M. Zarny, et al, "I2NSF Data Center Use Cases", <draft-
zarny-i2nsf-data-center-use-cases-00>, Oct 2014.
[I2NSF-MOBILE] M. Qi, et al, "Integrated Security with Access
Network Use Case", <draft-qi-i2nsf-access-network-usecase-
00>, Oct 2014
[I2NSF-Problem] L. Dunbar, et al "Interface to Network Security
Functions Problem Statement", <draft-dunbar-i2nsf-problem-
statement-01>, Jan 2015
[ACL-MODEL] D. Bogdanovic, et al, "Network Access Control List (ACL)
YANG Data Model", <draft-ietf-net-acl-model-00>, Nov 2014.
[gs_NFV] ETSI NFV Group Specification, Network Functions
Virtualizsation (NFV) Use Cases. ETSI GS NFV 001v1.1.1,
2013.
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[NW-2011] J. Burke, "The Pros and Cons of a Cloud-Based Firewall",
Network World, 11 November 2011
[SC-MobileNetwork] W. Haeffner, N. Leymann, "Network Based Services
in Mobile Network", IETF87 Berlin, July 29, 2013.
[I2NSF-Demo] Y. Xie, et al, "Interface to Network Security Functions
Demo Outline Design", <draft-xie-i2nsf-demo-outline-
design-00>, April 2015.
[ITU-T-X1036] ITU-T Recommendation X.1036, "Framework for creation,
storage, distribution and enforcement of policies for
network security", Nov 2007.
13. Acknowledgments
Acknowledgements to xxx for his review and contributions.
This document was prepared using 2-Word-v2.0.template.dot.
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Authors' Addresses
Edward Lopez
Fortinet
899 Kifer Road
Sunnyvale, CA 94086
Phone: +1 703 220 0988
Email: elopez@fortinet.com
Diego Lopez
Telefonica
Email: diego.r.lopez@telefonica.com
XiaoJun Zhuang
China Mobile
Email: zhuangxiaojun@chinamobile.com
Linda Dunbar
Huawei
Email: Linda.Dunbar@huawei.com
Joe Parrott
BT
Email: joe.parrott@bt.com
Ramki Krishnan
Dell
Email: ramki_krishnan@dell.com
Seetharama Rao Durbha
CableLabs
Email: S.Durbha@cablelabs.com
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