--- 1/draft-ietf-i2nsf-applicability-04.txt 2018-09-11 09:13:15.812519680 -0700 +++ 2/draft-ietf-i2nsf-applicability-05.txt 2018-09-11 09:13:15.864520930 -0700 @@ -1,26 +1,26 @@ I2NSF Working Group J. Jeong Internet-Draft Sungkyunkwan University Intended status: Informational S. Hyun -Expires: January 18, 2019 Chosun University +Expires: March 15, 2019 Chosun University T. Ahn Korea Telecom S. Hares Huawei D. Lopez Telefonica I+D - July 17, 2018 + September 11, 2018 Applicability of Interfaces to Network Security Functions to Network- Based Security Services - draft-ietf-i2nsf-applicability-04 + draft-ietf-i2nsf-applicability-05 Abstract This document describes the applicability of Interface to Network Security Functions (I2NSF) to network-based security services in Network Functions Virtualization (NFV) environments, such as firewall, deep packet inspection, or attack mitigation engines. Status of This Memo @@ -30,157 +30,143 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. 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." - This Internet-Draft will expire on January 18, 2019. + This Internet-Draft will expire on March 15, 2019. Copyright Notice Copyright (c) 2018 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 (https://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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 3. I2NSF Framework . . . . . . . . . . . . . . . . . . . . . . . 4 - 3.1. Time-dependent Web Access Control Service . . . . . . . . 5 - 4. I2NSF Framework with SFC . . . . . . . . . . . . . . . . . . 7 - 5. I2NSF Framework with SDN . . . . . . . . . . . . . . . . . . 9 - 5.1. Firewall: Centralized Firewall System . . . . . . . . . . 11 - 5.2. Deep Packet Inspection: Centralized VoIP/VoLTE Security + 3. I2NSF Framework . . . . . . . . . . . . . . . . . . . . . . . 3 + 4. Time-dependent Web Access Control Service . . . . . . . . . . 5 + 5. I2NSF Framework with SFC . . . . . . . . . . . . . . . . . . 6 + 6. I2NSF Framework with SDN . . . . . . . . . . . . . . . . . . 9 + 6.1. Firewall: Centralized Firewall System . . . . . . . . . . 11 + 6.2. Deep Packet Inspection: Centralized VoIP/VoLTE Security System . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 5.3. Attack Mitigation: Centralized DDoS-attack Mitigation + 6.3. Attack Mitigation: Centralized DDoS-attack Mitigation System . . . . . . . . . . . . . . . . . . . . . . . . . 14 - 6. I2NSF Framework with NFV . . . . . . . . . . . . . . . . . . 16 - 7. Security Considerations . . . . . . . . . . . . . . . . . . . 19 - 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 19 - 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 19 - 10. Informative References . . . . . . . . . . . . . . . . . . . 20 - Appendix A. Changes from draft-ietf-i2nsf-applicability-03 . . . 23 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23 + 7. I2NSF Framework with NFV . . . . . . . . . . . . . . . . . . 16 + 8. Security Considerations . . . . . . . . . . . . . . . . . . . 18 + 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18 + 10. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 18 + 11. Informative References . . . . . . . . . . . . . . . . . . . 19 + Appendix A. Changes from draft-ietf-i2nsf-applicability-04 . . . 22 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 1. Introduction - Interface to Network Security Functions (I2NSF) defined a framework + Interface to Network Security Functions (I2NSF) defines a framework and interfaces for interacting with Network Security Functions (NSFs). The I2NSF framework allows heterogeneous NSFs developed by - different security solution vendors to be used in the NFV environment - by utilizing the capabilities of such products and the virtualization - of security functions in the NFV platform. In the I2NSF framework, - each NSF initially registers the profile of its own capabilities into - the system in order for themselves to be available in the system. In - addition, the Security Controller registers itself to the I2NSF user - so that the user can request security services to the Security - Controller. - - This document describes the applicability of I2NSF framework to - network-based security services with a use case of time-dependent web - access control. This document also describes integrating I2NSF - framework with Software-Defined Networking (SDN) technology for - efficient security services and use cases, such as firewall + different security solution vendors to be used in the Network + Functions Virtualization (NFV) environment [ETSI-NFV] by utilizing + the capabilities of such products and the virtualization of security + functions in the NFV platform. In the I2NSF framework, each NSF + initially registers the profile of its own capabilities into the + system in order for themselves to be available in the system. In + addition, the Security Controller is validated by the I2NSF Client + (also called I2NSF User) that the user is employing, so that the user + can request security services through the Security Controller. - [opsawg-firewalls], Deep Packet Inspection (DPI), and Distributed - Denial of Service (DDoS) attack mitigation. We implemented the I2NSF - framework based on SDN for these use cases, and the implementation - successfully verified the effectiveness of the I2NSF framework. + This document illustrates the applicability of the I2NSF framework + with four different scenarios: (i) the enforcement of time-dependent + web access control; (ii) the application of I2NSF to a Service + Function Chaining (SFC) environment [RFC7665]; (iii) the integration + of the I2NSF framework with Software-Defined Networking (SDN) + [RFC7149] to provide different security functionality such as + firewalls [opsawg-firewalls], Deep Packet Inspection (DPI), and + Distributed Denial of Service (DDoS) attack mitigation; (iv) the use + of NFV as supporting technology. The implementation of I2NSF in + these scenarios has allowed us to verify the applicability and + effectiveness of the I2NSF framework for a variety of use cases. 2. Terminology This document uses the terminology described in [RFC7149], [ITU-T.Y.3300], [ONF-OpenFlow], [ONF-SDN-Architecture], [ITU-T.X.1252], [ITU-T.X.800], [RFC8329], [i2nsf-terminology], [consumer-facing-inf-im], [consumer-facing-inf-dm], - [i2nsf-nsf-cap-im], [nsf-facing-inf-dm], [registration-inf-im], - [registration-inf-dm], and [nsf-triggered-steering]. In addition, - the following terms are defined below: + [i2nsf-nsf-cap-im], [nsf-facing-inf-dm], [registration-inf-dm], and + [nsf-triggered-steering]. In addition, the following terms are + defined below: o Software-Defined Networking (SDN): A set of techniques that enables to directly program, orchestrate, control, and manage network resources, which facilitates the design, delivery and operation of network services in a dynamic and scalable manner [ITU-T.Y.3300]. o Firewall: A service function at the junction of two network segments that inspects every packet that attempts to cross the boundary. It also rejects any packet that does not satisfy certain criteria for, for example, disallowed port numbers or IP addresses. o Centralized Firewall System: A centralized firewall that can establish and distribute policy rules into network resources for - efficient firewall management. These rules can be managed - dynamically by a centralized server for firewall. SDN can work as - a network-based firewall system through a standard interface - between an SDN switch and a firewall function as a vitual network - function (VNF). + efficient firewall management. o Centralized VoIP Security System: A centralized security system that handles the security functions required for VoIP and VoLTE - services. SDN can work as a network-based security system through - a standard interface between an SDN switch and a VoIP/VoLTE - security function as a VNF. + services. o Centralized DDoS-attack Mitigation System: A centralized mitigator that can establish and distribute access control policy rules into - network resources for efficient DDoS-attack mitigation. These - rules can be managed dynamically by a centralized server for DDoS- - attack mitigation. The SDN controller and switches can - cooperatively work as a network-based firewall system through a - standard interface between an SDN switch and a firewall function - as a VNF running in the SDN controller. + network resources for efficient DDoS-attack mitigation. 3. I2NSF Framework - This section describes an I2NSF framework and its use case. Figure 1 - shows an I2NSF framework [RFC8329] to support network-based security - services. As shown in Figure 1, I2NSF User can use security - functions by delivering high-level security policies, which specify - security requirements the I2NSF user wants to enforce, to the - Security Controller via the Consumer-Facing Interface + This section summarizes the I2NSF framework as defined in [RFC8329]. + As shown in Figure 1, an I2NSF User can use security functions by + delivering high-level security policies, which specify security + requirements that the I2NSF user wants to enforce, to the Security + Controller via the Consumer-Facing Interface [consumer-facing-inf-im][consumer-facing-inf-dm]. The Security Controller receives and analyzes the high-level security policies from an I2NSF User, and identifies what types of security capabilities are required to meet these high-level security policies. The Security Controller then identifies NSFs that have the required security capabilities, and generates low-level security policies for each of the NSFs so that the high-level security policies are - eventually enforced by those NSFs. Finally, the Security Controller - sends the generated low-level security policies to the NSFs - [i2nsf-nsf-cap-im][nsf-facing-inf-dm]. + eventually enforced by those NSFs [policy-translation]. Finally, the + Security Controller sends the generated low-level security policies + to the NSFs [i2nsf-nsf-cap-im][nsf-facing-inf-dm]. The Security Controller requests NSFs to perform low-level security - services via the NSF-Facing Interface. The NSFs are enabled as - Virtual Network Functions (VNFs) on top of virtual machines through - Network Functions Virtualization (NFV) [ETSI-NFV]. In addition, the - Security Controller uses the I2NSF Registration Interface - [registration-inf-im][registration-inf-dm] to communicate with - Developer's Management System (called Developer's Mgmt System) for - registering (or deregistering) the developer's NSFs into (or from) - the NFV system using the I2NSF framework. + services via the NSF-Facing Interface. The developers (or vendors) + inform the Security Controller of the capabilities of the NSFs + through the I2NSF Registration Interface [registration-inf-dm] for + registering (or deregistering) the corresponding NSFs. The Consumer-Facing Interface between an I2NSF User and the Security Controller can be implemented using, for example, RESTCONF [RFC8040]. Data models specified by YANG [RFC6020] describe high-level security policies to be specified by an I2NSF User. The data model defined in [consumer-facing-inf-dm] can be used for the I2NSF Consumer-Facing Interface. +------------+ | I2NSF User | @@ -202,112 +188,109 @@ Figure 1: I2NSF Framework The NSF-Facing Interface between the Security Controller and NSFs can be implemented using NETCONF [RFC6241]. YANG data models describe low-level security policies for the sake of NSFs, which are translated from the high-level security policies by the Security Controller. The data model defined in [nsf-facing-inf-dm] can be used for the I2NSF NSF-Facing Interface. The Registration Interface between the Security Controller and the - Developer's Mgmt System can be implemented by RESTCONF [RFC8040]. - The data model defined in [registration-inf-dm] can be used for the - I2NSF Registration Interface. + Developer's Management System can be implemented by RESTCONF + [RFC8040]. The data model defined in [registration-inf-dm] can be + used for the I2NSF Registration Interface. Also, the I2NSF framework can enforce multiple chained NSFs for the - low-level security policies by means of service function chaining - (SFC) techniques for the I2NSF architecture described in - [nsf-triggered-steering]. + low-level security policies by means of SFC techniques for the I2NSF + architecture described in [nsf-triggered-steering]. - The following describes a security service scenario using the I2NSF - framework. + The following sections describe different security service scenarios + illustrating the applicability of the I2NSF framework. -3.1. Time-dependent Web Access Control Service +4. Time-dependent Web Access Control Service This service scenario assumes that an enterprise network - administrator wants to control the staff members' access to Facebook - during business hours. The following is an example high-level - security policy rule that the administrator requests: Block the staff - members' access to Facebook from 9 am to 6 pm. The administrator - sends this high-level security policy to the security controller, - then the security controller identifies required secuity - capabilities, e.g., IP address and port number inspection - capabilities and URL inspection capability. In this scenario, it is - assumed that the IP address and port number inspection capabilities - are required to check whether a received packet is an HTTP packet - from a staff member. The URL inspection capability is required to - check whether the target URL of a received packet is facebook.com or - not. + administrator wants to control the staff members' access to a + particular Interner service (e.g., Example.com) during business + hours. The following is an example high-level security policy rule + that the administrator requests: Block the staff members' access to + Example.com from 9 AM to 6 PM. The administrator sends this high- + level security policy to the Security Controller, then the Security + Controller identifies required security capabilities, e.g., IP + address and port number inspection capabilities and URL inspection + capability. In this scenario, it is assumed that the IP address and + port number inspection capabilities are required to check whether a + received packet is an HTTP packet from a staff member. The URL + inspection capability is required to check whether the target URL of + a received packet is in the Example.com domain or not. The Security Controller maintains the security capabilities of each NSF running in the I2NSF system, which have been reported by the Developer's Management System via the Registation interface. Based on this information, the Security Controller identifies NSFs that can - perform the IP address and port number inspection and URL inspection. - In this scenario, it is assumed that an NSF of firewall has the IP - address and port number inspection capabilities and an NSF of web - filter has URL inspection capability. + perform the IP address and port number inspection and URL inspection + [policy-translation]. In this scenario, it is assumed that an NSF of + firewall has the IP address and port number inspection capabilities + and an NSF of web filter has URL inspection capability. The Security Controller generates low-level security rules for the NSFs to perform IP address and port number inspection, URL inspection, and time checking. Specifically, the Security Controller may interoperate with an access control server in the enterprise network in order to retrieve the information (e.g., IP address in use, company identifier (ID), and role) of each employee that is currently using the network. Based on the retrieved information, the Security Controller generates low-level security rules to check whether the source IP address of a received packet matches any one being used by a staff member. In addition, the low-level security rules should be able to determine that a received packet is of HTTP protocol. The low-level security rules for web filter checks that - the target URL field of a received packet is equal to facebook.com. + the target URL field of a received packet is equal to Example.com. Finally, the Security Controller sends the low-level security rules of the IP address and port number inspection to the NSF of firewall and the low-level rules for URL inspection to the NSF of web filter. The following describes how the time-dependent web access control service is enforced by the NSFs of firewall and web filter. - 1. A staff member tries to access Fackbook.com during business - hours, e.g., 10 am. + 1. A staff member tries to access Example.com during business hours, + e.g., 10 AM. 2. The packet is forwarded from the staff member's device to the firewall, and the firewall checks the source IP address and port number. Now the firewall identifies the received packet is an HTTP packet from the staff member. 3. The firewall triggers the web filter to further inspect the packet, and the packet is forwarded from the firewall to the web - filter. Service Function Chaining (SFC) technology can be - utilized to support such packet forwarding in the I2NSF framework - [nsf-triggered-steering]. + filter. SFC technology can be utilized to support such packet + forwarding in the I2NSF framework [nsf-triggered-steering]. 4. The web filter checks the target URL field of the received - packet, and realizes the packet is toward Facebook.com. The web + packet, and realizes the packet is toward Example.com. The web filter then checks that the current time is in business hours. If so, the web filter drops the packet, and consequently the - staff member's access to Facebook during business hours is + staff member's access to Example.com during business hours is blocked. -4. I2NSF Framework with SFC +5. I2NSF Framework with SFC In the I2NSF architecture, an NSF can trigger an advanced security - action (e.g., DPI and DDoS attack mitigation) on a packet based on - the result of its own security inspection of the packet. For - example, a firewall triggers further inspection of a suspicious - packet with DPI. For this advanced security action to be fulfilled, - the suspicious packet should be forwarded from the current NSF to the - successor NSF. Service Function Chaining (SFC) [RFC7665] is a - technology that enables this advanced security action by steering a - packet with multiple service functions (e.g., NSFs), and this - technology can be utilized by the I2NSF architecture to support the - advanced security action. + action (e.g., DPI or DDoS attack mitigation) on a packet based on the + result of its own security inspection of the packet. For example, a + firewall triggers further inspection of a suspicious packet with DPI. + For this advanced security action to be fulfilled, the suspicious + packet should be forwarded from the current NSF to the successor NSF. + SFC [RFC7665] is a technology that enables this advanced security + action by steering a packet with multiple service functions (e.g., + NSFs), and this technology can be utilized by the I2NSF architecture + to support the advanced security action. SFC generally requires classifiers and service function forwarders (SFFs); classifiers are responsible for determining which service function path (SFP) (i.e., an ordered sequence of service functions) a given packet should pass through, according to pre-configured classification rules, and SFFs perform forwarding the given packet to the next service function (e.g., NSF) on the SFP of the packet by referring to their forwarding tables. In the I2NSF architecture with SFC, the Security Controller can take responsibilities of generating classification rules for classifiers and forwarding tables for SFFs. @@ -360,68 +343,69 @@ the packet to the classifier. Based on the metadata information, the classifier searches an SFP which includes an NSF with the required security capability, changes the SFP-related information (e.g., service path identifier and service index [RFC8300]) of the packet with the new SFP that has been found, and then forwards the packet to the SFF. When receiving the packet, the SFF checks the SFP-related information such as the service path identifier and service index contained in the packet and forwards the packet to the next NSF on the SFP of the packet, according to its forwarding table. -5. I2NSF Framework with SDN +6. I2NSF Framework with SDN This section describes an I2NSF framework with SDN for I2NSF applicability and use cases, such as firewall, deep packet inspection, and DDoS-attack mitigation functions. SDN enables some - packet filtering rules to be enforced in the network switches by - controlling their packet forwarding rules. By taking advantage of - this capability of SDN, it is possible to optimize the process of - security service enforcement in the I2NSF system. + packet filtering rules to be enforced in network forwarding elements + (e.g., switch) by controlling their packet forwarding rules. By + taking advantage of this capability of SDN, it is possible to + optimize the process of security service enforcement in the I2NSF + system. Figure 3 shows an I2NSF framework [RFC8329] with SDN networks to support network-based security services. In this system, the - enforcement of security policy rules is divided into the SDN switches - and NSFs. Especially, SDN switches enforce simple packet filtering - rules that can be translated into their packet forwarding rules, - whereas NSFs enforce NSF-related security rules requiring the - security capabilities of the NSFs. For this purpose, the Security - Controller instructs the Switch Controller via NSF-Facing Interface - so that SDN switches can perform the required security services with - flow tables under the supervision of the Switch Controller (i.e., SDN - Controller). + enforcement of security policy rules is divided into the SDN + forwarding elements (e.g., switch) and NSFs. Especially, SDN + forwarding elements enforce simple packet filtering rules that can be + translated into their packet forwarding rules, whereas NSFs enforce + NSF-related security rules requiring the security capabilities of the + NSFs. For this purpose, the Security Controller instructs the SDN + Controller via NSF-Facing Interface so that SDN forwarding elements + can perform the required security services with flow tables under the + supervision of the SDN Controller. As an example, let us consider two different types of security rules: Rule A is a simple packet fltering rule that checks only the IP address and port number of a given packet, whereas rule B is a time- consuming packet inspection rule for analyzing whether an attached file being transmitted over a flow of packets contains malware. Rule - A can be translated into packet forwarding rules of SDN switches and - thus be enforced by the switches. In contrast, rule B cannot be - enforced by switches, but it can be enforced by NSFs with anti- - malware capability. Specifically, a flow of packets is forwarded to - and reassembled by an NSF to reconstruct the attached file stored in - the flow of packets. The NSF then analyzes the file to check the - existence of malware. If the file contains malware, the NSF drops - the packets. + A can be translated into packet forwarding rules of SDN forwarding + elements and thus be enforced by these elements. In contrast, rule B + cannot be enforced by forwarding elements, but it has to be enforced + by NSFs with anti-malware capability. Specifically, a flow of + packets is forwarded to and reassembled by an NSF to reconstruct the + attached file stored in the flow of packets. The NSF then analyzes + the file to check the existence of malware. If the file contains + malware, the NSF drops the packets. In an I2NSF framework with SDN, the Security Controller can analyze given security policy rules and automatically determine which of the - given security policy rules should be enforced by SDN switches and - which should be enforced by NSFs. If some of the given rules - requires security capabilities that can be provided by SDN switches, - then the Security Controller instructs the Switch Controller via NSF- - Facing Interface so that SDN switches can enforce those security - policy rules with flow tables under the supervision of the Switch - Controller (i.e., SDN Controller). Or if some rules require security - capabilities that can be provided by not SDN switches but NSFs, then - the Security Controller instructs relevant NSFs to enforce those - rules. + given security policy rules should be enforced by SDN forwarding + elements and which should be enforced by NSFs. If some of the given + rules requires security capabilities that can be provided by SDN + forwarding elements, then the Security Controller instructs the SDN + Controller via NSF-Facing Interface so that SDN forwarding elements + can enforce those security policy rules with flow tables under the + supervision of the SDN Controller. Or if some rules require security + capabilities that cannot be provided by SDN forwarding elements but + by NSFs, then the Security Controller instructs relevant NSFs to + enforce those rules. +------------+ | I2NSF User | +------------+ ^ | Consumer-Facing Interface v +-------------------+ Registration +-----------------------+ |Security Controller|<-------------------->|Developer's Mgmt System| +-------------------+ Interface +-----------------------+ @@ -436,61 +420,60 @@ | | | v | +--------+ | | SFF | | +--------+ | ^ | | | V SDN Network +--|----------------------------------------------------------------+ | V NSF-Facing Interface | - | +-----------------+ | - | |Switch Controller| | - | +-----------------+ | + | +----------------+ | + | | SDN Controller | | + | +----------------+ | | ^ | | | SDN Southbound Interface | | v | | +--------+ +--------+ +--------+ +--------+ | | |Switch 1|-|Switch 2|-|Switch 3|......|Switch m| | | +--------+ +--------+ +--------+ +--------+ | +-------------------------------------------------------------------+ Figure 3: An I2NSF Framework with SDN Network The following subsections introduce three use cases for cloud-based security services: (i) firewall system, (ii) deep packet inspection system, and (iii) attack mitigation system. [RFC8192] -5.1. Firewall: Centralized Firewall System +6.1. Firewall: Centralized Firewall System A centralized network firewall can manage each network resource and - firewall rules can be managed flexibly by a centralized server for - firewall (called Firewall). The centralized network firewall - controls each switch for the network resource management and the - firewall rules can be added or deleted dynamically. + apply common rules to individual network elements (e.g., switch). + The centralized network firewall controls each forwarding element, + and firewall rules can be added or deleted dynamically. The procedure of firewall operations in this system is as follows: - 1. A switch forwards an unknown flow's packet to one of the Switch + 1. A switch forwards an unknown flow's packet to one of the SDN Controllers. - 2. The Switch Controller forwards the unknown flow's packet to an + 2. The SDN Controller forwards the unknown flow's packet to an appropriate security service application, such as the Firewall. 3. The Firewall analyzes, typically, the headers and contents of the packet. 4. If the Firewall regards the packet as a malicious one with a - suspicious pattern, it reports the malicious packet to the Switch + suspicious pattern, it reports the malicious packet to the SDN Controller. - 5. The Switch Controller installs new rules (e.g., drop packets with + 5. The SDN Controller installs new rules (e.g., drop packets with the suspicious pattern) into underlying switches. 6. The suspected packets are dropped by these switches. Existing SDN protocols can be used through standard interfaces between the firewall application and switches [RFC7149][ITU-T.Y.3300][ONF-OpenFlow] [ONF-SDN-Architecture]. Legacy firewalls have some challenges such as the expensive cost, performance, management of access control, establishment of policy, @@ -521,69 +504,69 @@ are permitted or denied for firewall within a specific organization network under management. Thus, a centralized view is helpful to determine security policies for such a network. o Packet-based access mechanism: Packet-based access mechanism is not enough for firewall in practice since the basic unit of access control is usually users or applications. Therefore, application level rules can be defined and added to the firewall system through the centralized server. -5.2. Deep Packet Inspection: Centralized VoIP/VoLTE Security System +6.2. Deep Packet Inspection: Centralized VoIP/VoLTE Security System A centralized VoIP/VoLTE security system can monitor each VoIP/VoLTE - flow and manage VoIP/VoLTE security rules controlled by a centralized - server for VoIP/VoLTE security service called VoIP Intrusion - Prevention System (IPS). The VoIP/VoLTE security system controls - each switch for the VoIP/VoLTE call flow management by manipulating - the rules that can be added, deleted or modified dynamically. + flow and manage VoIP/VoLTE security rules, according to the + configuration of a VoIP/VoLTE security service called VoIP Intrusion + Prevention System (IPS). This centralized VoIP/VoLTE security system + controls each switch for the VoIP/VoLTE call flow management by + manipulating the rules that can be added, deleted or modified + dynamically. - A centralized VoIP/VoLTE security system can cooperate with a network - firewall to realize VoIP/VoLTE security service. Specifically, a - network firewall performs basic security checks of an unknown flow's - packet observed by a switch. If the network firewall detects that - the packet is an unknown VoIP call flow's packet that exhibits some - suspicious patterns, then it triggers the VoIP/VoLTE security system - for more specialized security analysis of the suspicious VoIP call - packet. + The centralized VoIP/VoLTE security system can cooperate with a + network firewall to realize VoIP/VoLTE security service. + Specifically, a network firewall performs basic security checks of an + unknown flow's packet observed by a switch. If the network firewall + detects that the packet is an unknown VoIP call flow's packet that + exhibits some suspicious patterns, then it triggers the VoIP/VoLTE + security system for more specialized security analysis of the + suspicious VoIP call packet. The procedure of VoIP/VoLTE security operations in this system is as follows: - 1. A switch forwards an unknown flow's packet to the Switch - Controller, and the Switch Controller further forwards the - unknown flow's packet to the Firewall for basic security - inspection. + 1. A switch forwards an unknown flow's packet to the SDN Controller, + and the SDN Controller further forwards the unknown flow's packet + to the Firewall for basic security inspection. 2. The Firewall analyzes the header fields of the packet, and figures out that this is an unknown VoIP call flow's signal packet (e.g., SIP packet) of a suspicious pattern. 3. The Firewall triggers an appropriate security service function, such as VoIP IPS, for detailed security analysis of the suspicious signal packet. That is, the firewall sends the packet to the Service Function Forwarder (SFF) in the I2NSF framework [nsf-triggered-steering], as shown in Figure 3. The SFF forwards the suspicious signal packet to the VoIP IPS. 4. The VoIP IPS analyzes the headers and contents of the signal packet, such as calling number and session description headers [RFC4566]. 5. If, for example, the VoIP IPS regards the packet as a spoofed packet by hackers or a scanning packet searching for VoIP/VoLTE devices, it drops the packet. In addition, the VoIP IPS requests - the Switch Controller to block that packet and the subsequent + the SDN Controller to block that packet and the subsequent packets that have the same call-id. - 6. The Switch Controller installs new rules (e.g., drop packets) - into underlying switches. + 6. The SDN Controller installs new rules (e.g., drop packets) into + underlying switches. 7. The illegal packets are dropped by these switches. Existing SDN protocols can be used through standard interfaces between the VoIP IPS application and switches [RFC7149][ITU-T.Y.3300] [ONF-OpenFlow][ONF-SDN-Architecture]. Legacy hardware based VoIP IPS has some challenges, such as provisioning time, the granularity of security, expensive cost, and the establishment of policy. The I2NSF framework can resolve the @@ -607,54 +590,54 @@ that we need to add VoIP IPS on each network resource. To solve this, each network resource can be managed centrally such that a single VoIP IPS is manipulated by a centralized server. o The establishment of policy: Policy should be established for each network resource. However, it is difficult to describe what flows are permitted or denied for VoIP IPS within a specific organization network under management. Thus, a centralized view is helpful to determine security policies for such a network. -5.3. Attack Mitigation: Centralized DDoS-attack Mitigation System +6.3. Attack Mitigation: Centralized DDoS-attack Mitigation System A centralized DDoS-attack mitigation can manage each network resource - and manipulate rules to each switch through a centralized server for - DDoS-attack mitigation (called DDoS-attack Mitigator). The - centralized DDoS-attack mitigation system defends servers against - DDoS attacks outside private network, that is, from public network. + and manipulate rules to each switch through a common server for DDoS- + attack mitigation (called DDoS-attack Mitigator). The centralized + DDoS-attack mitigation system defends servers against DDoS attacks + outside the private network, that is, from public networks. Servers are categorized into stateless servers (e.g., DNS servers) and stateful servers (e.g., web servers). For DDoS-attack mitigation, traffic flows in switches are dynamically configured by traffic flow forwarding path management according to the category of servers [AVANT-GUARD]. Such a managenent should consider the load balance among the switches for the defense against DDoS attacks. The procedure of DDoS-attack mitigation operations in this system is as follows: 1. A Switch periodically reports an inter-arrival pattern of a - flow's packets to one of the Switch Controllers. + flow's packets to one of the SDN Controllers. - 2. The Switch Controller forwards the flow's inter-arrival pattern - to an appropriate security service application, such as DDoS- - attack Mitigator. + 2. The SDN Controller forwards the flow's inter-arrival pattern to + an appropriate security service application, such as DDoS-attack + Mitigator. 3. The DDoS-attack Mitigator analyzes the reported pattern for the flow. 4. If the DDoS-attack Mitigator regards the pattern as a DDoS attack, it computes a packet dropping probability corresponding - to suspiciousness level and reports this DDoS-attack flow to - Switch Controller. + to suspiciousness level and reports this DDoS-attack flow to the + SDN Controller. - 5. The Switch Controller installs new rules into switches (e.g., + 5. The SDN Controller installs new rules into switches (e.g., forward packets with the suspicious inter-arrival pattern with a dropping probability). 6. The suspicious flow's packets are randomly dropped by switches with the dropping probability. For the above centralized DDoS-attack mitigation system, the existing SDN protocols can be used through standard interfaces between the DDoS-attack mitigator application and switches [RFC7149] [ITU-T.Y.3300][ONF-OpenFlow][ONF-SDN-Architecture]. @@ -688,33 +671,33 @@ for DDoS-attack mitigation. In addition, DDoS-attack mitigation rules can be dynamically added for new DDoS attacks. o The establishment of policy: Policy should be established for each network resource. However, it is difficult to describe what flows are permitted or denied for new DDoS-attacks (e.g., DNS reflection attack) within a specific organization network under management. Thus, a centralized view is helpful to determine security policies for such a network. - So far this document has described the procedure and impact of the + So far this section has described the procedure and impact of the three use cases for network-based security services using the I2NSF framework with SDN networks. To support these use cases in the proposed data-driven security service framework, YANG data models described in [consumer-facing-inf-dm], [nsf-facing-inf-dm], and [registration-inf-dm] can be used as Consumer-Facing Interface, NSF- Facing Interface, and Registration Interface, respectively, along with RESTCONF [RFC8040] and NETCONF [RFC6241]. -6. I2NSF Framework with NFV +7. I2NSF Framework with NFV - This section discusses the implementation of the I2NSF framework with - Network Functions Virtualization (called NFV). + This section discusses the implementation of the I2NSF framework + using Network Functions Virtualization (NFV). +--------------------+ +-------------------------------------------+ | ---------------- | | I2NSF User (OSS/BSS) | | | NFV | | +------+------------------------------------+ | | Orchestrator +-+ | | Consumer-Facing Interface | -----+---------- | | +------|------------------------------------+ | | | | | -----+---------- (a) ----------------- | | | | | | | Security |-------| Developer's | | | | | | | |Controller(EM)| |Mgmt System(EM)| | | | | | @@ -739,22 +722,22 @@ | | ----------- ----------- ----------- | | | | | | | Compute | | Storage | | Network | | | | | | | | Hardware| | Hardware| | Hardware| | | | | | | ----------- ----------- ----------- | | | | | | Hardware Resources | | | NFV Management | | +---------------------------------------+ | | and Orchestration | +-------------------------------------------+ +--------------------+ (a) = Registration Interface (b) = Ve-Vnfm Interface - Figure 4: I2NSF Framework Implementation in NFV Reference - Architectural Framework + Figure 4: I2NSF Framework Implementation with respect to the NFV + Reference Architectural Framework NFV is a promising technology for improving the elasticity and efficiency of network resource utilization. In NFV environments, NSFs can be deployed in the forms of software-based virtual instances rather than physical appliances. Virtualizing NSFs makes it possible to rapidly and flexibly respond to the amount of service requests by dynamically increasing or decreasing the number of NSF instances. Moreover, NFV technology facilitates flexibly including or excluding NSFs from multiple security solution vendors according to the changes on security requirements. In order to take advantages of the NFV @@ -803,67 +786,63 @@ allocated resources. 5. Once the NSF instance has been created by the VNFM, the DMS performs the initial configurations of the NSF instance and then notifies the Security Controller of the NSF instance. 6. After being notified of the created NSF instance, the Security Controller delivers low-level security policy rules to the NSF instance for policy enforcement. - The I2NSF framework can be implemented based on the NFV architecture. - Note that the registration of the capabilities of NSFs is performed - through the Registration Interface and the life-cycle management for - NSFs (VNFs) is performed through the Ve-Vnfm interface between the - DMS and VNFM, as shown in Figure 4. More details about the I2NSF - framework based on the NFV reference architecture are described in - [i2nsf-nfv-architecture]. + We can conclude that the I2NSF framework can be implemented based on + the NFV architecture framework. Note that the registration of the + capabilities of NSFs is performed through the Registration Interface + and the lifecycle management for NSFs (VNFs) is performed through the + Ve-Vnfm interface between the DMS and VNFM, as shown in Figure 4. + More details about the I2NSF framework based on the NFV reference + architecture are described in [i2nsf-nfv-architecture]. -7. Security Considerations +8. Security Considerations - The I2NSF framework with SDN networks in this document is derived - from the I2NSF framework [RFC8329], so the security considerations of - the I2NSF framework should be included in this document. Therefore, - proper secure communication channels should be used the delivery of - control or management messages among the components in the proposed - framework. + The same security considerations for the I2NSF framework [RFC8329] + are applicable to this document. This document shares all the security issues of SDN that are specified in the "Security Considerations" section of [ITU-T.Y.3300]. -8. Acknowledgments +9. Acknowledgments This work was supported by Institute for Information & communications Technology Promotion (IITP) grant funded by the Korea government (MSIP) (No.R-20160222-002755, Cloud based Security Intelligence Technology Development for the Customized Security Service Provisioning). -9. Contributors +10. Contributors I2NSF is a group effort. I2NSF has had a number of contributing authors. The following are considered co-authors: o Hyoungshick Kim (Sungkyunkwan University) o Jinyong Tim Kim (Sungkyunkwan University) o Hyunsik Yang (Soongsil University) - o Younghan Kim (Soongsil University) o Jung-Soo Park (ETRI) o Se-Hui Lee (Korea Telecom) + o Mohamed Boucadair (Orange) -10. Informative References +11. Informative References [AVANT-GUARD] Shin, S., Yegneswaran, V., Porras, P., and G. Gu, "AVANT- GUARD: Scalable and Vigilant Switch Flow Management in Software-Defined Networks", ACM CCS, November 2013. [consumer-facing-inf-dm] Jeong, J., Kim, E., Ahn, T., Kumar, R., and S. Hares, "I2NSF Consumer-Facing Interface YANG Data Model", draft- ietf-i2nsf-consumer-facing-interface-dm-01 (work in @@ -926,30 +905,30 @@ October 2013. [ONF-SDN-Architecture] ONF, "SDN Architecture", June 2014. [opsawg-firewalls] Baker, F. and P. Hoffman, "On Firewalls in Internet Security", draft-ietf-opsawg-firewalls-01 (work in progress), October 2012. + [policy-translation] + Yang, J., Jeong, J., and J. Kim, "Security Policy + Translation in Interface to Network Security Functions", + draft-yang-i2nsf-security-policy-translation-01 (work in + progress), July 2018. + [registration-inf-dm] Hyun, S., Jeong, J., Roh, T., Wi, S., and J. Park, "I2NSF Registration Interface YANG Data Model", draft-hyun-i2nsf- - registration-dm-05 (work in progress), July 2018. - - [registration-inf-im] - Hyun, S., Jeong, J., Roh, T., Wi, S., and J. Park, "I2NSF - Registration Interface Information Model", draft-hyun- - i2nsf-registration-interface-im-06 (work in progress), - July 2018. + registration-dm-06 (work in progress), July 2018. [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session Description Protocol", RFC 4566, July 2006. [RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. [RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. Bierman, "Network Configuration Protocol (NETCONF)", @@ -970,31 +949,34 @@ (I2NSF): Problem Statement and Use Cases", RFC 8192, July 2017. [RFC8300] Quinn, P., Elzur, U., and C. Pignataro, "Network Service Header (NSH)", RFC 8300, January 2018. [RFC8329] Lopez, D., Lopez, E., Dunbar, L., Strassner, J., and R. Kumar, "Framework for Interface to Network Security Functions", RFC 8329, February 2018. -Appendix A. Changes from draft-ietf-i2nsf-applicability-03 +Appendix A. Changes from draft-ietf-i2nsf-applicability-04 The following changes have been made from draft-ietf-i2nsf- - applicability-03: + applicability-04: - o In Section 4, NSF-Facing Interface is used between Security - Controller and Classifier (or SFF) in order to configure - Classifier (or SFF) for SFC-based NSF chaining. + o A more precise description of the basic I2NSF flows is provided. - o In Section 6, Developer's Management System is implemented as EM - rather than VNFM in the NFV reference architecture. + o The structure of the document makes each discussed use case be an + applicability statement according to the applied technology, such + as SFC, SDN, and NFV. + + o In Section 6, Switch Controller is replaced by SDN Controller for + the terminology consistency in SDN standards. Switch is replaced + by forwarding element as a general term. Authors' Addresses Jaehoon Paul Jeong Department of Software Sungkyunkwan University 2066 Seobu-Ro, Jangan-Gu Suwon, Gyeonggi-Do 16419 Republic of Korea