Network Working Group U. Chunduri, Ed. Internet-Draft A. Clemm Intended status: Informational Huawei Technologies Expires: January 4, 2018 M. Menth University of Tuebingen July 3, 2017 Identity Use Cases in IDEAS draft-ccm-ideas-identity-use-cases-01 Abstract IDentity-EnAbled networkS (IDEAS) introduce the concept of Identity into networking. This concept includes an Identity/Identifier split, which complements existing Locator/Identifier separation technologies and benefit from both novel communication paradigms. This document summarizes some conceptual use cases to illustrate the usefulness of IDEAS. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC2119 [RFC2119]. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. 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 http://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 4, 2018. Copyright Notice Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved. Chunduri, et al. Expires January 4, 2018 [Page 1] Internet-Draft Identity Use Cases in IDEAS July 2017 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Acronyms . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Need for Identity . . . . . . . . . . . . . . . . . . . . . . 4 3. Identity (IDy) in IDEAS . . . . . . . . . . . . . . . . . . . 4 4. Identity Use Cases . . . . . . . . . . . . . . . . . . . . . 5 4.1. Privacy . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.2. Unified Policies . . . . . . . . . . . . . . . . . . . . 6 4.2.1. Access Restriction Policies . . . . . . . . . . . . . 7 4.3. Uses of Metadata . . . . . . . . . . . . . . . . . . . . 7 4.4. Access Security and Manageability . . . . . . . . . . . . 7 4.5. Delay-Tolerant Networking (DTN) . . . . . . . . . . . . . 8 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 7. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 8.1. Normative References . . . . . . . . . . . . . . . . . . 9 8.2. Informative References . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 1. Introduction An Internet Protocol (IP) [RFC0791] address signifies both a Communication Entity's (Section 1.1) Location and its Identification. Location and Identification separation protocols, for example HIP [RFC7401] and LISP [RFC6830], introduced the concept of Identifier and separated this information from the Locator (IP address in this case). The Location/Identifier split separates Location and Identification function for a specific networking device, i.e., the Identifier denotes a device while the Locator denotes a routable network interface. With Location/Identifier split, multiple benefits in networking can be realized, e.g., in the areas of mobility, network virtualization, traffic engineering, security, software-defined networking, and others. Chunduri, et al. Expires January 4, 2018 [Page 2] Internet-Draft Identity Use Cases in IDEAS July 2017 IDEAS goes one step further and makes a distinction between Identity and Identifier, and introduces an Identity/Identifier split. The abstraction of an Identity and the corresponding split from Identifiers can bring additional benefits that can be combined with Location/Identifier separation. The abstracted Identity still corresponds to network layer, like Locator/Identifier and not related to transport or application Identities. These potential benefits are in the areas of privacy i.e., the ability to have multiple identifiers for the same entity which can be used for anonymous communication, identity-based access controls at the Mapping System (MS), and application of various policies uniformly across Identifiers pertaining to an Identity. Identity also enables various management aspects at the mapping system efficiently. 1.1. Acronyms Communication Entity: A device used for IP-based (in some case Layer-2 based) data communication Entity: Refer to Communication Entity GRIDS: GeneRic Identity Services - a mapping and Identity services system that will be defined in the context of IDEAS. This goes beyond traditional mapping of Location/Identifier and can include Identity based services(e.g. policy/metadata/ grouping service). HIP: Host Identity Protocol IDf: Identifier - denotes information to unambiguously identify an entity within a given scope. Examples HIP HIT [RFC7401] and LISP EID [RFC6830]. There is no constraint on the format, obfuscation or routability of an Identifier. IDy: Identity - a unique identifier for a communications entity that MAY be assigned by the GRIDS-provider and that is used by the provider to identify and authenticate the communications entity, but that is not revealed in the packet headers. LOC: Locator, for example, IPv4/IPv6 based LISP: The Locator/ID Separation Protocol Chunduri, et al. Expires January 4, 2018 [Page 3] Internet-Draft Identity Use Cases in IDEAS July 2017 Metadata: Metadata is data about an Identity. The metadata may contain information such as the nature of the entity for example or opaque information about the Identity MS: Traditional Mapping Server for LOC/IDf protocols (e.g. HIP RVS, LISP-DDT) 2. Need for Identity An entity can use multiple Identifiers for anonymous communication in the data plane [I-D.farinacci-lisp-eid-anonymity] or for other reasons, for example to representing different locators simultaneously. When multiple Identifiers are in use, the notion of Layer-3 Identity to represent the communication entity uniquely helps in following ways. a. Unique and Permanent Identity representing the entity enables authentication (AUTH) with the mapping and Identity services infrastructure. While it is possible to do AUTH on Identifiers those are not permanently associated to the entity. Moreover, AUTH operation is a relatively an expensive and inefficient procedure (compared to LOC resolution for example) and can cause excessive startup delays for lot of applications. b. Data plane anonymization allows entities to communicate anonymously from the outside observers. Identity provides de- anonymization for various data plane ephemeral Identifiers, if required, and enables resolution of which entity is behind these identifiers for legitimate users (entities itself in some cases). c. Identity enables managing access restriction policies and metadata (which MAY represent type of the entity in some cases) regardless of which Identifier used in data plane communication by the entity. Without Identity any access restrictions kept on Identifiers would be easily invalidated, if the peer entity simply changes the Identifier. The above requirements for having a stable network layer Identity is further detailed in Section 4. Section 4 also shows how another abstraction of Identity from Identifiers help to enable various services in the data communication with in IDEAS. 3. Identity (IDy) in IDEAS An Identity uniquely identifies a Communication Entity. IDy MAY be unicoded or an ASCII string, which MAY have a partial structure and MAY be given by the provider of the IDy services. Typically, an IDy Chunduri, et al. Expires January 4, 2018 [Page 4] Internet-Draft Identity Use Cases in IDEAS July 2017 SHOULD NOT be revealed unencrypted on the wire or shared with other entities to make IDy a private enclave. IDy is used for authentication of the Communication Entity and it MAY be represented by multiple Identifiers (IDf's) in the data plane. IDy can be seen as a 'permanent Identifier' of a communication entity with certain properties (for example not used in data plane) and with certain additional attributes which are common to all Identifiers of a communication entity. Also for privacy reasons, access to the [IDy, IDf] mapping information may be restricted to a defined set of communication entities. These communication patterns require new, GeneRic ID Services (GRIDS), which map these Identifiers to their Identities and provide additional services based on the Identities (apart from the traditional Identifier/Location mapping). In the following (Section 4) various IDy use cases point out benefits of Identity in IDEAS. The following diagram Figure 1 illustrates a simplified relation of Identity , Identifier and Locators [IDy, IDf, LOC]. +---------------------------------------------------------------+ | Identity (IDy) | Policy | Metadata | MI | | |(private/public) | |(private) | +---------------------------------------------------------------+ | +---------------------+--------------------+ | | | V V V +------------------------+ +--------------+ +-------------------+ |Identifier(IDf)-1 | LOC1| | IDf-2 | LOC2 |...| IDf-n| LOC1..LOCm | |(long-lived) | | (ephemeral) | | | +------------------------+ +--------------+ +-------------------+ MI - Management and Security Information Figure 1: Identity and Identifier, Location Relationship Only public part of the policy, metadata (see Section 7) SHOULD be shared with other providers of GRIDS, for example, where the LOC resolution request is originated. 4. Identity Use Cases Identity potentially brings value to new breed of entities connecting to the Internet. The need for an Identity can be described by a few simple uses of the same as specified below. Chunduri, et al. Expires January 4, 2018 [Page 5] Internet-Draft Identity Use Cases in IDEAS July 2017 4.1. Privacy To communicate with a device on a network, a LOC is needed. In current [IDf, LOC] protocols, a Mapping Server (MS) stores the [IDf,LOC] mapping. The resolution request or lookup of an IDf to the MS will return the LOC. Generally, an entity with a certain Identity may use various Identifiers for communication. Only the Identifier is visible on the wire. Changing the IDf frequently makes it hard to track the entity by outside observers on the Internet and thus improves privacy of the communication entities. While it may be desirable to change the IDf every now and then for privacy purposes, the notion of Identity in addition to IDf is important a) to retain the ability to look up a communication entity by a 'long-lived IDf' and b) to convey an authorized network entity who is behind a given (ephemeral) IDf that is visible on the wire. To put it simply, while the IDy of a communicating entity is obfuscated to outside observers, it is revealed to communicating parties with a legitimate need to know. Legitimate parties include either end of entities itself or regulatory authorities or authorized edge nodes (routers/IDf based firewalls) in the network. 4.2. Unified Policies Networks may treat traffic differently depending on the IDy of source or destination. E.g., certain traffic may access the network directly, other traffic may need to pass a firewall, or other traffic is entirely blocked. Based on IDy of communication peers involved, and independent of the particular IDf used in a data packet (see Section 4.1), traffic may be treated with different Quality of Service (QoS). Likewise, the use of alternative IDfs for the same system may allow for different treatment of traffic for the same system depending on how the system is referred to. This can be leveraged by combining the enforcement of network policies with policies that guide selective mapping responses. E.g., some requesting groups may receive an empty response from GRIDS Infrastructure for IDfs referring to a certain IDy, others receive an IDf resulting in strict security treatment of future traffic, and trusted groups receive an IDf resulting in rather loose security treatment. Chunduri, et al. Expires January 4, 2018 [Page 6] Internet-Draft Identity Use Cases in IDEAS July 2017 4.2.1. Access Restriction Policies An entity may define that it wants to communicate only with certain other entities. To achieve this, an entity MAY define a rule regarding who can request and obtain its IDf. The GRIDS Infrastructure will send a negative or empty response when it detects that the combination of resolution query and its initiator does not pass the rule validation test. One example of this policy is, restriction of LOC resolution and hence allowing data traffic from only from the dealer/manufacturer of a vehicular node. Moreover, network-based access control may filter based on IDfs which are visible in the traffic, but this can be done in an elegant way through an association related to the IDy. IDy may be looked-up to ensure if communication is still allowed after IDf change, for example. By basing access control on the notion of Identity, enforcement and maintainability of access control rules is greatly simplified as it does not need to track IDf changes or the introduction of new IDfs for the same IDy. 4.3. Uses of Metadata The GRIDS Infrastructure is envisioned to store Metadata (Section 1.1) and provide some search functionality. The GRIDS Infrastructure with [IDy, IDf] may be a means to find a set of IDys with certain metadata provided that they have agreed to be searchable (allow discovery). Moreover, their IDfs can be looked up. E.g., it may be possible to find out the current IDfs of a set of deployed devices of particular type. This allows to locate them via [IDf, LOC] mappings and possibly manage them. Identity also allows to have metadata associated it to be applied, regardless of which IDf is used to refer it. This association makes the management of metadata easier, because it does not need to be maintained separately and redundantly for every IDf. 4.4. Access Security and Manageability Identity can be used for storing access security credentials to the GRIDS and subscription information of the user entity securely as opposed to various Identifiers representing the entity. As secure registration to the GRIDS would be an expensive operation, this SHOULD be restricted to IDy and (ephemeral) IDfs can be generated and can be given rather securely using the same secure channel. The IDy's lifecycle is inherently tied to the lifecycle of the entity but not with multiple Identifiers which can be added or removed. Hence, Identity allows separation of lifecycle of IDy to be different Chunduri, et al. Expires January 4, 2018 [Page 7] Internet-Draft Identity Use Cases in IDEAS July 2017 from Identifiers, which enables to extend the "right-to-be-forgotten" concerning personal data to network identifier data, if required. There are various possible scenarios on why a long-lived IDfs by a communication entity has to be withdrawn. Common cases involved lost/stolen device or misused Identifiers for example. 4.5. Delay-Tolerant Networking (DTN) Entities may be only temporarily reachable on the Internet. When they are not reachable, proxies may be used to receive their traffic. To that end, a IDy MAY register one of the IDfs of its proxy with the GRIDS Infrastructure that this node can, e.g., receive traffic for that node and later forward to it when the node is again online. A major application field may be in the IoT with mobile and intermittently connected devices 5. Acknowledgements Thanks to Padma Pillay-Esnault for so many conversations around Identity and its potential uses in IDEAS. Authors would like to thank detailed reviews and suggestions from Dino Farinacci, Joel Halpern, Jeff Tantsura, Jim Guichard, Christian Huitema, Dave Meyers, Liu Bingyang and Yangfei. 6. IANA Considerations This document has no actions for IANA. 7. Security Considerations This document further abstracts Identity from the Identifier in current Identifier/Locator protocols. This abstraction gives significant security benefits in Identity enables networks with respect to anonymization of communications on the wire and access controls at the GRIDS specified in [I-D.padma-ideas-problem-statement]. The IDy policy SHOULD be limited in scope and only public part of the policy SHOULD be sharable to other GRIDS Providers. Storage and Security of the data itself at the GRIDS-provider is critical. A separate threat analysis for security aspects of private/public portions of the IDy data SHOULD be done once the architecture is evolved. 8. References Chunduri, et al. Expires January 4, 2018 [Page 8] Internet-Draft Identity Use Cases in IDEAS July 2017 8.1. Normative References [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, DOI 10.17487/RFC0791, September 1981, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . 8.2. Informative References [I-D.farinacci-lisp-eid-anonymity] Farinacci, D., Pillay-Esnault, P., and W. Haddad, "LISP EID Anonymity", draft-farinacci-lisp-eid-anonymity-02 (work in progress), April 2017. [I-D.padma-ideas-problem-statement] Pillay-Esnault, P., Boucadair, M., Jacquenet, C., Fioccola, G., and A. Nennker, "Problem Statement for Identity Enabled Networks", draft-padma-ideas-problem- statement-01 (work in progress), March 2017. [RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The Locator/ID Separation Protocol (LISP)", RFC 6830, DOI 10.17487/RFC6830, January 2013, . [RFC7401] Moskowitz, R., Ed., Heer, T., Jokela, P., and T. Henderson, "Host Identity Protocol Version 2 (HIPv2)", RFC 7401, DOI 10.17487/RFC7401, April 2015, . Authors' Addresses Uma Chunduri (editor) Huawei Technologies 2330 Central Expressway Santa Clara, CA 95050 USA Email: uma.chunduri@huawei.com Chunduri, et al. Expires January 4, 2018 [Page 9] Internet-Draft Identity Use Cases in IDEAS July 2017 Alexander Clemm Huawei Technologies 2330 Central Expressway Santa Clara, CA 95050 USA Email: ludwig@clemm.org Michael Menth University of Tuebingen Germany Email: menth@uni-tuebingen.de Chunduri, et al. Expires January 4, 2018 [Page 10]