Network Working Group E. Lopez Internet Draft Fortinet Intended status: Informational D. Lopez Expires: April 2016 Telefonica L. Dunbar J. Strassner Huawei X. Zhuang China Mobile J. Parrott BT R Krishnan Dell S. Durbha CableLabs October 19, 2015 Framework for Interface to Network Security Functions draft-merged-i2nsf-framework-04.txt Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. This document may not be modified, and derivative works of it may not be created, except to publish it as an RFC and to translate it into languages other than English. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." xxx, et al. Expires April 19, 2016 [Page 1] Internet-Draft I2NSF Framework October 2015 The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on April 19, 2009. Copyright Notice Copyright (c) 2015 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Abstract This document defines a set of abstractions for guiding the functionality provided by 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 on NSF capability and functionality. 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 the context of sessions in which the packet is associated. Table of Contents 1. Introduction...................................................3 xxx, et al. Expires April 19, 2016 [Page 2] Internet-Draft I2NSF Framework October 2015 2. Conventions used in this document..............................4 3. Interfaces to Flow-based NSFs..................................4 4. Reference Models in Managing NSFs..............................6 4.1. NSF Facing (Capability Layer) Interface...................7 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 for governing NSFs.........................14 6.1. Capability Layer Rules and Monitoring....................14 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 the 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 that could limit NSFs internal functionality and capability. 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 the network what they are willing to receive, in other words, the security rules for their specific traffic. It also provides a 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. xxx, et al. Expires April 19, 2016 [Page 3] Internet-Draft I2NSF Framework October 2015 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]. 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] inspects packets in the order that they are received. The Interface to Flow-based NSFs can be generally grouped into three types: xxx, et al. Expires April 19, 2016 [Page 4] Internet-Draft I2NSF Framework October 2015 1) Configuration - deals with the management and configuration of the NSF device itself, such as port address configurations. Configuration deals with attributes that are relatively static. 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. Due to the need of applications/controllers to dynamically control what traffic they need 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. In other words, the introduction of I2NSF standards should not make it easier for attackers to compromise the network. 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 xxx, et al. Expires April 19, 2016 [Page 5] Internet-Draft I2NSF Framework October 2015 - 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 that aids in their integration within legacy, SDN, and/or NFV environments, while avoiding potential constraints which could limit their functional capabilities. Even though security functions come in a 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, SDN/NFV integration; - Functional Profile - a functional profile is a specific organization of characteristics and/or behavior of that define the functionality offered by an entity (e.g., IPS:, signature file, Anti-virus file, URL filtering file, etc.). Integrated and one-pass checks on the content of packets are examples of a functional profile. 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 flow-based NSFs. The following figure shows various interfaces for managing the provisioning & monitoring aspects of flow-based NSFs. xxx, et al. Expires April 19, 2016 [Page 6] Internet-Draft I2NSF Framework October 2015 +------------------------------------------+ | 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 the 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 the Server Layer Interface in the I2NSF xxx, et al. Expires April 19, 2016 [Page 7] Internet-Draft I2NSF Framework October 2015 context. The I2NSF Service Layer allows the client to define and monitor the client specific policies and their execution status. A single client layer policy may need multiple NSFs or NSF instantiations that are used collectively to achieve the desired 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 the capabilities of their NSFs. The Registration Interface can be defined statically or instantiated dynamically at runtime. If new functionality that is exposed to the user is added to an NSF, then the vendor MUST notify the Service Provider management system of its updated interface. 4.4. The network connecting the Security Controller and NSFs Most likely, the NSFs are not directly attached to the Security Controller; for example, NSFs can be distributed across the network. The network that connects the Security Controller with the NSFs can be the same network that carries the data traffic, or can be a dedicated network for management purposes only. In 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: xxx, et al. Expires April 19, 2016 [Page 8] Internet-Draft I2NSF Framework October 2015 - Closed environments, where there is only one administrative domain. Less restrictive access control and simpler validation can be used inside the domain because of the protected environment. - Open environments, where some NSFs (virtual or physical) can be hosted in external administrative domains or reached via external network domains. This requires more restrictive security controls to be placed over the I2NSF interface. The information over the I2NSF interfaces must use trusted channels, such as TLS, SASL (RFC4422), or the combination of the two. Over the Open Environment, I2NSF needs to provide identity information, along with additional data that Authentication, Authorization, and Accounting (AAA) frameworks can use. This enables those frameworks to perform AAA functions on the I2NSF traffic. 4.5. Interface to vNSFs Even though there is no difference between virtual network security functions (vNSF) and physical NSFs from the 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 a network. When different instantiations are visible to the Security Controller, different policies may be applied to different instantiations of one single NSF (e.g., to reflect the different roles that each vNSF is designated for). - 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 disseminates 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 moved to another vNSF of the same type when client flows are moved from one vNSF to another. xxx, et al. Expires April 19, 2016 [Page 9] Internet-Draft I2NSF Framework October 2015 - Multiple vNSFs may share the same physical platform - There may be scenarios where multiple vNSFs collectively perform the security policies needed. +------------------------+ | 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, due to technological capacity increases, integration of platforms, and new threats. 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, destination port, and/or other attributes of the packet header). Packets that do not match policy are rejected. Note that additional functions, such as logging and notification of a system administrator, could optionally be enforced as well. . 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. Note that additional functions, such as xxx, et al. Expires April 19, 2016 [Page 10] Internet-Draft I2NSF Framework October 2015 notification of a system administrator, could optionally be enforced as well. . 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. Note that additional functions, such as logging and notification of a system administrator, could optionally be enforced as well. 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 the context of sessions in 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, and the specific profiles and the actions they can apply. An example of a 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 anything that can influence the action(s) taken by the NSF, such as time of day, location, session state, 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: | xxx, et al. Expires April 19, 2016 [Page 11] Internet-Draft I2NSF Framework October 2015 | | protocol | | IPv4 Header | dest port | | | src port | | | src address | | | dest address | | | dscp | | | length | | | flags | | | ttl | | | | | IPv6 Header | | | | addr | | | protocol/nh | | | src port | | | dest port | | | src address | | | dest address | | | length | | | traffic class | | | hop limit | | | flow label | | | dscp | | | | | 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 | xxx, et al. Expires April 19, 2016 [Page 12] Internet-Draft I2NSF Framework October 2015 | | | 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 | | | | +---------------+-------------------------------------------+ | Time | time span | | | time occurrence | +---------------+-------------------------------------------+ | Events | Event URL, variables | +---------------+-------------------------------------------+ | Location | Text string, GPS coords, URL | +---------------+-------------------------------------------+ | Connection | Internet (unsecured), Internet | | Type | (secured by VPN, etc.), Intranet, ... | +---------------+-------------------------------------------+ | Direction | Inbound, Outbound | +---------------+-------------------------------------------+ | State | Authentication State | | | Authorization State | | | Accounting State | | | Session State | +---------------+-------------------------------------------+ Table 2: Object Capability Index +-----------------------------------------------------------+ | Action Capability Index | +---------------+-------------------------------------------+ | Ingress port | SFC header termination, | | | VxLAN header termination | +---------------+-------------------------------------------+ | | Pass | | Actions | Deny | | | Mirror | xxx, et al. Expires April 19, 2016 [Page 13] Internet-Draft I2NSF Framework October 2015 | | 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 for governing NSFs 6.1. Capability Layer Rules and Monitoring The purpose of the Capability Layer is to define explicit rules for individual NSFs to treat packets, as well as methods to monitor the execution status of those functions. [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 Lists 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. For example, most vendors' IPS/IDS have their proprietary functions/profiles. One of the goals of I2NSF is to define a 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 context surrounding the packets). xxx, et al. Expires April 19, 2016 [Page 14] Internet-Draft I2NSF Framework October 2015 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 is the base for ITU-T X.1036 [ITU-T- X1036]: +-------------------------+ | Capability-Layer-Rules | +-------------------------+ | | +---------+ +--------+ +---------+ |- Pass |Compound | | | | Simple +-|- Deny |Condition| | action | +--+ Actions| |- Mirror +----+----+ +----+---+ | +---------+ |- Count |<-------+ +---------------+ |- client fun +---+------+ | | ++---+-----+| | | +---------+ | 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 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. xxx, et al. Expires April 19, 2016 [Page 15] Internet-Draft I2NSF Framework October 2015 6.2. Service Layer Policy This layer is for clients or Application Controller 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. These customers may express expectations or intent. Customers may also express guidelines such as which certain types of destinations are not allowed for certain groups. 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" o enable basic parental control o enable "school protection control" o allow Internet traffic from 8:30 to 20:00 o scan email for malware detection protect traffic to corporate network with 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 controller when user's service requirements have been changed. Some service layer policies may not be granted because the carrier or Enterprises imposes additional constraints on what the user can have. [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. There have been several industry initiatives to address network policies, such as OpenStack's Group-based Policy (GBP), IETF Policy xxx, et al. Expires April 19, 2016 [Page 16] Internet-Draft I2NSF Framework October 2015 Core Information Model-PCIM [RFC3060, RFC3460], and others. I2NSF will not work on general network service policies, but instead will define a standard interface for clients/applications to inform the Flow-based NSFs on the rules for treating traffic. However, the notion of Groups (or roles), Target, Context (or conditions), and Action do cover what is needed for clients/applications to express the rules on how their flows can 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. Using PCIM (RFC3060, which ITU-T X.1036 was based on) as a basis is possible. However, RFC3060 was created for general network policies. This means that in some areas, it provides more than what I2NSF needs, and in other areas, it needs extension. This is especially pronounced regarding Policy Context and Policy Conditions (e.g., the direction, 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 can be 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. - 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. xxx, et al. Expires April 19, 2016 [Page 17] Internet-Draft I2NSF Framework October 2015 - 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 xxx, et al. Expires April 19, 2016 [Page 18] Internet-Draft I2NSF Framework October 2015 7. Capability Negotiation When an NSF can't perform the desired provisioning (e.g., due to resource constraints), it MUST 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 Controller: - For example, Video Conference Mgr/Controller needs to dynamically inform network to allow or deny flows (some of which are encrypted) based on 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 xxx, et al. Expires April 19, 2016 [Page 19] Internet-Draft I2NSF Framework October 2015 - 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. xxx, et al. Expires April 19, 2016 [Page 20] Internet-Draft I2NSF Framework October 2015 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", , Oct 2014. [I2NSF-DC] M. Zarny, et al, "I2NSF Data Center Use Cases", , Oct 2014. [I2NSF-MOBILE] M. Qi, et al, "Integrated Security with Access Network Use Case", , Oct 2014 [I2NSF-Problem] L. Dunbar, et al "Interface to Network Security Functions Problem Statement", , Jan 2015 [ACL-MODEL] D. Bogdanovic, et al, "Network Access Control List (ACL) YANG Data Model", , Nov 2014. [gs_NFV] ETSI NFV Group Specification, Network Functions Virtualizsation (NFV) Use Cases. ETSI GS NFV 001v1.1.1, 2013. xxx, et al. Expires April 19, 2016 [Page 21] Internet-Draft I2NSF Framework October 2015 [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", , 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. xxx, et al. Expires April 19, 2016 [Page 22] Internet-Draft I2NSF Framework October 2015 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 John Strassner Huawei John.sc.Strassner@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 xxx, et al. Expires April 19, 2016 [Page 23]