ICNRG J. Hong Internet-Draft ETRI Intended status: Informational Lijun Dong Expires: September 14, 2017 Huawei T. You ETRI Cedric Westphal Huawei Y-G. Hong ETRI GQ Wang Huawei Jianping Wang City University Hong Kong March 13, 2017 Requirements for Name Resolution Service in ICN draft-jhong-icnrg-nrs-requirements-00.txt Abstract This document discusses the motivation and requirements for Name Resolution Service (NRS) in ICN. The NRS in ICN is to translate object names into routing hints such as locators, where names are location-independent and locators are network addresses. 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 September 14, 2017. Hong, et al. Expires September 14, 2017 [Page 1] Internet-Draft NRS Requirements March 2017 Copyright Notice Copyright (c) 2017 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. Hong, et al. Expires September 14, 2017 [Page 2] Internet-Draft NRS Requirements March 2017 Table of Contents 1. Introduction ................................................ 4 2. Conventions and Terminology .................................. 6 3. Motivation .................................................. 7 3.1. Name Resolution Service in ICN .......................... 7 3.2. Handling Heterogeneous Names in ICN ..................... 8 3.3. Handling Dynamism in ICN ................................ 8 4. Requirements for NRS in ICN .................................. 9 4.1. Requirements on Operability ............................. 9 4.1.1. Scalability ........................................ 9 4.1.2. Delay sensitivity .................................. 9 4.1.3. Time transiency ................................... 10 4.1.4. Minimum inter-domain traffic ...................... 10 4.1.5. Fault tolerance ................................... 10 4.1.6. Resolution guarantee .............................. 10 4.1.7. Accuracy ......................................... 11 4.1.8. Heterogeneity ..................................... 11 4.1.9. Unspecified content name .......................... 12 4.2. Requirements on Manageability .......................... 12 4.2.1. Manageability ..................................... 12 4.2.2. Deployability ..................................... 12 4.2.3. Interoperability .................................. 12 4.2.4. Support for manifest .............................. 13 4.2.5. Resolution result selection ....................... 13 4.3. Requirements on Security ............................... 14 4.3.1. Accessibility ..................................... 14 4.3.2. Authentication .................................... 14 4.3.3. Data confidentiality .............................. 14 4.3.4. Privacy .......................................... 14 5. Use cases of NRS ........................................... 15 5.1. Flat Name routing support .............................. 15 5.2. Publisher Mobility support ............................. 15 5.3. Scalable Routing support ............................... 17 5.4. Nameless object support ................................ 17 6. Security Considerations ..................................... 17 7. IANA Considerations ........................................ 18 8. Conclusions ................................................ 18 9. References ................................................. 18 9.1. Normative References ................................... 18 9.2. Informative References ................................. 18 Hong, et al. Expires September 14, 2017 [Page 3] Internet-Draft NRS Requirements March 2017 1. Introduction The current Internet is a host-centric networking, where hosts are uniquely identified with IP addresses and communication is possible between any pair of hosts. Thus, information in the current Internet is identified by the name of host where the information is stored. In contrast to the host-centric networking, the primary communication objects in Information-centric networking (ICN) are the named data objects (NDOs) and they are uniquely identified by the location-independent names. Thus, ICN aiming to the efficient dissemination and retrieval of the NDOs in a global scale has been identified and acknowledged as the most promising technology for the future Internet architecture to overcome the limitations of the current Internet such as scalability, mobility, etc.[28][29] ICN also has been emerged as a candidate architecture for IoT environment since IoT focuses on data and information rather than end-to-end communications [30][31][32]. In addition, the following ICN features are fulfilling well the architectural requirements of IoT such as naming, name resolution, scalability, resource constraints, mobility, caching, security, privacy, etc.[33][34]: - Naming of data, devices, and services independently from their locations - Distributed caching and processing - Decoupling between sender and receiver - Mobility support - Authentication and verification of content Since naming data independently from the current location where it is stored is a primary concept of ICN, how to discover the NDO using the location-independent name is one of the most important design challenges in ICN. Thus, most ICN architectures, such as DONA[4], PURSUIT[5], NDN[7][10], CCN[8], SAIL[6], MobilityFirst[9] are centered around routing for content retrieval. ICN routing generally involves three steps: - Name resolution[11][12][14][15][17][18]: matches/translates a content name to locators of providers/sources that can provide the content. Hong, et al. Expires September 14, 2017 [Page 4] Internet-Draft NRS Requirements March 2017 - Content request routing: routes the content request towards the producer either based on the name or the locator. The process of name resolution and content request routing can be integrated. If integrated, the content request is routed by name, such as in NDN/CCN. If not integrated, the content request is routed by the locator obtained from the previous name resolution step, such as in DONA, PURSUIT, SAIL, MobilityFirst. - Content delivery: Constructs a path for transferring the content from the provider to the requester. In the integrated approach, content can be routed using breadcrumbs left by the request to define a reverse path, or by some other mechanism, such as including a locator for the requester in the content request. In the uncombined approach, the content can be routed from the provider back to the request through an independent path. Thus the name resolution process in ICN architectures either can be separated from the message routing (e.g. routing of content request message) as a standalone process or can be integrated with the message routing as one combined process. The former is referred as standalone name resolution approach, the latter is referred as name based routing approach in this document. The following compares the standalone name resolution and name based routing approaches from different aspects: - Update message overhead: The update message overhead is due to the change of content reachability, which may include content caching or expiration, content producer mobility etc. The name based routing approach may require to flood part of the network for update propagation. In the worst case, the name based routing approach may flood the whole network (but mitigating techniques may be used to scope the flooding). The standalone name resolution approach only requires to update propagation in part of the name resolution overlay. - Resolution capability: The standalone name resolution approach can guarantee the resolution of any content in the network if it is registered to the name resolution overlay (assuming the content is being broadcast in the overlay after it is registered). On the other hand, the name based routing approach can only promise a high probability of content resolution, depending on the flooding scope of the content availability information (i.e. content publishing message and name based routing table). - Node failure impact: Nodes involved in the standalone name resolution approach are the name resolution overlay servers (e.g. Hong, et al. Expires September 14, 2017 [Page 5] Internet-Draft NRS Requirements March 2017 Resolution Handlers in DONA), while the nodes involved in the name based routing approach are routers which route messages based on locally maintained name based routing tables (e.g. NDN routers). Node failures in the standalone name resolution approach may cause some content resolution to fail even though the content is available. This problem does not exist in the name based routing approach because other alternative paths can be discovered to bypass the failed ICN routers, given the assumption that the network is still connected. - Maintained databases: The storage usage for the standalone name resolution approach is different from that of the name based routing approach. The standalone name resolution approach typically needs to maintain two databases: name to locator mapping in the name resolution overlay and routing tables in the routers on the data forwarding plane. The name based routing approach needs to maintain different databases: name routing table and optionally breadcrumbs for reverse routing of content back to the requester. Despite the coexistence of different name resolution approaches, the Name Resolution Service (NRS) is most essential service that shall be provided by the ICN infrastructure. Thus, in this document, we give the definition of NRS in ICN and discuss the motivation and the requirements in designing the NRS for ICN. 2. Conventions and Terminology 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]. Hong, et al. Expires September 14, 2017 [Page 6] Internet-Draft NRS Requirements March 2017 3. Motivation In this section, we give the definition of NRS in ICN and discuss the motivation why NRS is needed in ICN. 3.1. Name Resolution Service in ICN The Name Resolution Service (NRS) is defined as the service that is provided by ICN infrastructure to help a client to reach a specific piece of content, service, or host using a persistent name. The NRS could take the standalone name resolution approach to return the client with the locators of the content, which will be used by the underlying network as the identifier to route the client's request to one of the producers. There are several ICN projects that use the standalone name resolution approach such as DONA[4], PURSUIT[5], SAIL[6], MobilityFirst[9], IDNet[35], etc. The NRS could take the name based routing approach, which integrates the name resolution with the content request message routing as in NDN[7]/CCN[8]. In the case that the content request also specifies the reverse path, as in NDN/CCN, the name resolution mechanism also determines the routing path for the data. This adds a requirement on the name resolution service to propagate interest in a way that is consistent with the subsequent data forwarding. Namely, the interest must select a path for the data based upon the finding the copy of the content, but also properly delivering the data. The NRS could also take hybrid approach which can perform name based routing approach from the beginning, when it fails at certain router, the router can go back to the standalone name resolution approach. The alternative hybrid NRS approach also works, which can perform standalone name resolution approach to find locators of routers which can carry out the name based routing of the client's request. A hybrid approach would combine name resolution as a subset of routers on the path with some tunneling in between (say, across an administrative domain) so that only a few of the nodes in the architecture perform name resolution in the name-based routing approach. Hong, et al. Expires September 14, 2017 [Page 7] Internet-Draft NRS Requirements March 2017 Additionally, some other intermediary step may be included in the name resolution, namely the mapping of one name to other names, in order to facilitate the retrieval of named content, by way of a manifest[24][25]. The manifest is resolved using one of the two above approaches, and it may include further mapping of names to content and location. The steps for name resolution then become: first translate the manifest name into a location of a copy of the manifest; the manifest includes further names of the content components, and potentially locations for the content. The content is then retrieved by using these names and/or location, potentially resulting in additional name resolutions. No matter which approach is taken by the NRS in ICN, it is the most essential component or service of the ICN infrastructure. 3.2. Handling Heterogeneous Names in ICN In ICN design, a name is used to identify an entity, such as named data content, a device, an application, a service. ICN requires uniqueness and persistency of the name of any entity to ensure the reachability of the entity within certain scope and with proper authentication and trust guarantees. The name does not change with the mobility and multi-home of the corresponding entity. A client can always use this name to retrieve the content from network and verify the binding of the content and the name. Ideally, a name can include any form of identifier, which can be flat, hierarchical, and human readable or non-readable. 3.3. Handling Dynamism in ICN I ICN has the dynamic features like mobility, multi-homing, migration, and replication of named resources such as content, devices, services, etc. The dynamism of the names resources will be more in future networking contexts such as 5G or when services are virtualized over wider geography due to the namespace expansion into the routing/forwarding. Hong, et al. Expires September 14, 2017 [Page 8] Internet-Draft NRS Requirements March 2017 4. Requirements for NRS in ICN In this section, we provide the requirements for designing NRS in ICN in terms of operability, security and manageability, respectively. 4.1. Requirements on Operability The requirements on operability aspect are things that should be considered when the key operations of NRS are designed. 4.1.1. Scalability The NRS system must to be extremely scalable to support a large number of content objects as well as billions of users, who may access the system through various connection methods and devices. Especially in IoT applications, the data size is small but frequently generated by sensors. Message forwarding and processing, routing table building-up and name records propagation must be efficient and scalable. The memory requirement for NRS nodes should be achievable by the current memory technologies. 4.1.2. Delay sensitivity The name resolution process provided by the NRS must not introduce significant latencies. With more number of name record replications, the number of nodes involved in the name resolution may be reduced. For example, in the standalone name resolution approach, with the name record being replicated to higher hierarchy or the peer NRS server in the overlay, the name resolution can be responded more promptly. In the name based routing approach, with the content based routing table being broadcast within the larger scope in the network, the name resolution and request routing can have higher probability to successfully reach the nearer copy of the requested content. The NRS deployment should balance the number of nodes involved in the name resolution and the overhead/cost for the name record replication. To ensure the low latency, the NRS should be able to route a content request to the closest copy. Message forwarding and processing should be efficient and computation complexity should be reasonable low and affordable by the current processor technologies. Hong, et al. Expires September 14, 2017 [Page 9] Internet-Draft NRS Requirements March 2017 4.1.3. Time transiency The NRS should support time-transient content, which is frequently created in and disappearing from the network. This kind of content only stays in the network for a short time, which requires the NRS to be able to promptly reflect the records of them in the system. For example, some video clip only exists in the network for a very short time, which requires the NRS to promptly update their name records. 4.1.4. Minimum inter-domain traffic The NRS must attempt to minimize total traffic, and inter-domain traffic in particular. In order to achieve that, message propagation for name resolution and retrieval should retain the locality and should be kept in the network domain if that domain contains both the client and the content copy. For example, a client is requesting the temperature data of the building that he/she is residing in, the NRS should be able to return or route to the nearest gateway in the building that stores such data instead of a remote server in the cloud. 4.1.5. Fault tolerance The NRS must ensure resilience to node failures. After a NRS node fails, the NRS system must be able to restore the name records stored in the NRS node. The NRS must also ensure resolution failure at one NRS node would be resolved and corrected by other NRS nodes. For example, in the standalone name resolution approach, when a NRS overlay server fails, the name records should be able to transferred and recovered in its peer server or its replacement. In the name based approach, the failure of one ICN router does not cause much trouble in the name resolution, because the other alternative paths can be established that bypass the failed ICN router. However, it requires that the ICN router has propagated its name based routing information in the network. 4.1.6. Resolution guarantee The NRS must ensure the name resolution success if the matching content exists in the network, regardless of its popularity, number of cached copies. Hong, et al. Expires September 14, 2017 [Page 10] Internet-Draft NRS Requirements March 2017 4.1.7. Accuracy The NRS must provide accurate and up-to-date information on how to reach the producer(s) of requested content with minimum overhead in propagating the update information. Content mobility and expiration must be reflected in the corresponding records in the NRS system with minimum delay to guarantee the accurate resolution. For example, a content can be moved from one domain to another domain due to the mobility of the producer, then the old name record should be deleted from the NRS system and a new name record should be added and updated with minimum delay. 4.1.8. Heterogeneity There are heterogeneous content naming schemes[16][19] and name resolution approaches from different ICN architectures. For example: - Names in DONA[1] consist of the cryptographic hash of the principal's public key P and a label L uniquely identifying the information with respect to the principal. Name resolution in DONA is provided by specialized servers called Resolution Handlers (RHs). - Content in PURSUIT[5] is identified by a combination of a scope ID and a rendezvous ID. The scope ID represents the boundaries of a defined dissemination strategy for the content it contain. The rendezvous ID is the actual identity for a particular content. Name resolution in PURSUIT is handled by a collection of Rendezvous Nodes (RNs), which are implemented as a hierarchical Dynamic Hash Table (DHT)[13][14]. - Names in NDN/CCN[8][10] are hierarchical and may be similar to URLs. Each name component can be anything, including a dotted human- readable string or a hash value. NDN/CCN adopts the name based routing. The NDN router forwards the interest by doing the longest- match lookup in the Forwarding Information Base (FIB) based on the content name and the interest is stored in the Pending Interest Table (PIT). - In MobilityFirst[9], every network entity, content has a Global Unique Identifier (GUID). GUIDs are flat 160-bit strings with no semantic structure. Name Resolution in MobilityFirst all is carried out via a Global Name Resolution Service (GNRS). Although the existing naming schemes are different, they all need to provide basic functions for identifying a content, supporting trust provenance, content lookup and routing. The NRS may combine the Hong, et al. Expires September 14, 2017 [Page 11] Internet-Draft NRS Requirements March 2017 advantages of different mechanisms. The NRS may be able to provide a generic naming schema to resolve any type of content name, either it is flat or hierarchical. 4.1.9. Unspecified content name Currently, both the standalone name resolution and name based routing approaches assume that the content name is known (or potentially retrieved from some other service) and specified to the network by the client, which is sometimes not the case. A client may not know the exact name of the data that he/she is requesting. For example, a client wants to retrieve the temperature data on 07/21/2015 in San Diego. In this case, the client is only able to specify some semantics and contextual information of the data that he/she is looking for. The NRS may be able to resolve those requests by having a northbound interface to the other services, which can return the content name(s) matching the client's request. 4.2. Requirements on Manageability Requirements on manageability are things that should be considered in terms of the system management aspect. 4.2.1. Manageability NRS has to be manageable since some parts of the system may grow or shrink dynamically and a name resolution server may be added or deleted. 4.2.2. Deployability Deployability is important for a real world system. If the NRS can be deployed from the edges, then the deployment can be simplified. 4.2.3. Interoperability Considering the emergence of IoT applications, many standard bodies for IoT have settled their ways for resource/data management. For example: - oneM2M[19] uses tree structure to store resources. Each resource is addressable by its URI. oneM2M resources are linked together by parent-child relationship or link relationship with pointers. Hong, et al. Expires September 14, 2017 [Page 12] Internet-Draft NRS Requirements March 2017 Resource resolution is indicated in the hierarchical name of the resources. With one entrance, a client can go anywhere within the tree structure. As an example, a content is stored under the container with URI prefix of /CSEBase-ID/AE-ID/container ID/contentInstance-ID. From the URI of the content, a client would be able to easily do the name resolution and go to the oneM2M server identified by CSEBase-ID. - IETF CoRE[21] specifies the Resource Directory (RD) [23] for resource registration and resolution. A RD is a database that stores links about resources hosted by endpoints (EP), which are called RD entries. An EP is a server that is associated with a scheme (e.g. CoAP[22] by default, or HTTP), IP address and port. It is likely that a physical IoT node may host one or more Eps. The RD provides a set of RESTful interface for EPs to register and maintain sets of RD entries, and for clients to look up resources. In order for the ICN infrastructure to support IoT applications, the NRS should provide the interoperability between those existing resource registries as well as integration of them into the ICN infrastructure. The NRS should allow different providers to coexist and for requesters to choose one or more preferred providers on their own. 4.2.4. Support for manifest The NRS should support resolution using manifests. Namely, if a content object is described by a manifest, the NRS should support efficient recursive resolution of the names included in the manifest. Alternatively, if the manifest contains mapping of content names to location (for instance, DASH manifest may contain additional Base URL for a specific content stream), then this should be consistent with the mapping obtained from the NRS. 4.2.5. Resolution result selection The NRS may be able to return some of the active producers or all of them for the client's selection or select the best producer based on the client's criteria and context information, e.g. producer with least load, with least response time, etc. Hong, et al. Expires September 14, 2017 [Page 13] Internet-Draft NRS Requirements March 2017 4.3. Requirements on Security Requirements on security are things that should be considered in terms of the security aspect for both the node and data. 4.3.1. Accessibility The NRS system must be prevented from the malicious users attempting to hijack or corrupt name records. The name records must have proper access rights such that the information contained in the name record would not be revealed to unauthorized users. The name records may be associated within certain domain, and cannot be propagated outside the domain. For example, for content that is only shared within the community should be restricted within the community network, outside of which the content may not exist. 4.3.2. Authentication Users/nodes that register themselves with NRS server require the authentication to ensure who claims to be. For example, the attacker can act as a fake NRS server which causes disruption or intercepts the data. 4.3.3. Data confidentiality NRS has to keep the data confidentiality to prevent a lot of sensitive data from reaching unauthorized data requestor in IoT environment. 4.3.4. Privacy When a private data is registered in the system, NRS has to support the privacy to avoid the information leaking. Otherwise, unauthorized entity may disclose the privacy. Hong, et al. Expires September 14, 2017 [Page 14] Internet-Draft NRS Requirements March 2017 5. Use cases of NRS In this section, we describe usages of NRS in the ICN literature. 5.1. Flat Name routing support In ICN, data objects must be identified by names regardless their location or container [RFC 7927] and the names are divided into two types of schemes: hierarchical and flat namespaces. A hierarchical scheme used in CCN and NDN architectures has a structure similar to current URIs, where the hierarchy improves scalability of routing system. It is because the hierarchy enables aggregation of the name resulting in reducing the size of RIB or FIB as similar to IP routing system. In a flat scheme, on the other hand, name routing is not easy since names in a flat namespace cannot be aggregated anymore, which would cause more the scalability problem in routing system. In order to address such problem, a flat name is resolved to some information which is routable through NRS or a sort of NRS in various ICN literatures. In PURSUIT [5], names are flat and the rendezvous functions are defined for NRS, which is implemented by a set of Rendezvous Nodes (RNs), the Rendezvous Network (RENE). Thus a name consisted of a sequence of scope IDs and a single rendezvous ID is routed by RNs in RENE. Thus, PURSUIT decouples name resolution and data routing, where NRS is performed by the RENE. In MobilityFirst [9], a name called a global unique Identifier (GUID) derived from a human-readable name via a global naming service is flat typed 160-bits strings with self-certifying function. Thus, MobilityFirst defines a global name resolution service (GNRS) which resolves GUIDs to network addresses and decouples name resolution and data routing as similar to PURSUIT. 5.2. Publisher Mobility support In ICN literature, it is said that mobility can be achieved in fundamental feature of ICN. Especially, consumer or client mobility can be achieved by allowing information requests to basic procedure from different interfaces or through attachment point of the new network. Moreover, seamless mobility service in ICN ensures that content reception continues without any disruption in ICN application, so in consumer point of view, seamless mobility can be easily supported. Hong, et al. Expires September 14, 2017 [Page 15] Internet-Draft NRS Requirements March 2017 However, producer or publisher mobility in ICN is more complicated to be supported. If a publisher moves into different authority domain or network location, then the request for a content published by the moving publisher with origin name would be hardly forwarded to the moving publisher. Especially in a hierarchical name scheme, publisher mobility support is much harder than in a flat name scheme since the routing tables related in broad area should be updated according to the publisher movement. Therefore, various ICN literatures would adopt NRS to achieve the publisher mobility, where NRS can be implemented in different ways such as rendezvous mechanism, mapping, etc. In NDN, for publisher mobility support, rendezvous mechanisms have been proposed to build interests rendezvous (RV) with data generated by a mobile producer (MP) [36]. There can be classified two approaches such as chase mobile producer and rendezvous data. Regarding MP chasing, rendezvous acts as a mapping service that provides the mapping from the name of the data produced by the MP to the MP's current point of attachment (PoA) name. Alternatively, the RV serves as a home agent like as IP mobility support, so the RV enables consumer's interest message to tunnel towards the MP at the PoA. Regarding rendezvous data, moving the data produced by the MP have been hosting at data depot instead of forwarding interest messages. Thus a consumer's interest message can be forwarded to stationary place as called data rendezvous, so it would either return the data or fetch it using another mapping solution. Therefore, RV or other mapping functions are in the role of NRS in NDN. In [37], forwarding-label (FL) object is referred to enable identifier (ID) and locator (LID) namespaces to be split in ICN. Generally, IDs are managed by applications, while locators are managed by a network administrator, so that IDs are mapping to heterogeneous name schemes and LIDs are mapping to network domains or specific network elements. Thus the proposed FL object acts as a locator (LID) and provides the flexibility to forward Interest messages through mapping service between IDs and LIDs. Therefore, the mapping service in control plane infrastructure can be considered as NRS in this draft. In MobilityFirst [9], both consumer and publisher mobility can be primarily handled by the global name resolution service (GNRS) which resolves GUIDs to network addresses. Thus, the GNRS must be updated for mobility support when a network attached object changes its point of attachment, which differs from NDN/CCN. Hong, et al. Expires September 14, 2017 [Page 16] Internet-Draft NRS Requirements March 2017 5.3. Scalable Routing support In ICN, application names identifying contents are used directly for packet delivery, so ICN routers run a name-based routing protocol to build name-based routing and forwarding tables. As same as scalability of IP routing, if non-aggregated name prefixes are injected to the Default Route Free Zone (DFZ) of ICN, then they would be driving the growth of the DFZ routing table size. Thus a solution to keep the routing table size under control is needed, which can be done by defining indirection layer. In [38], a well-known concept of Map-and-Encap is applied to provide a simple and secure namespace mapping solution to address the routing scalability problem in NDN's DFZ. In the proposed map-and- encap design, data whose name prefixes do not exist in the DFZ forwarding table can be retrieved by a distributed mapping system called NDNS, which maintains and lookups the mapping information from a name to its globally routed prefixes. Therefore, NDNS is a kind of NRS. 5.4. Nameless object support In CCNx 1.0, the concept of "Nameless Objects" that are a Content Object without a Name is introduced to provide a means to move Content between storage replicas without having to rename or re-sign the content objects for the new name. Nameless Objects can be addressed by the ContentObjectHash that is to restrict Content Object matching by using SHA-256 hash [39]. An Interest message would still carry a Name and a ContentObjectHash, where a Name is used for routing, while a ContentObjectHash is used for matching. However, on the reverse path, if the Content Object's name is missing, it is a "Nameless Object" and only matches against the ContentObjectHash. Therefore, a consumer needs to resolve proper name and hashes through an outside system, which can be considered as NRS. 6. Security Considerations [TBD] Hong, et al. Expires September 14, 2017 [Page 17] Internet-Draft NRS Requirements March 2017 7. IANA Considerations This document makes no specific request of IANA. 8. Conclusions In this draft, we broaden the definition of NRS in the ICN infrastructure as the service which can help a client to reach a producer of the requested content. Thus the NRS could take the approaches of standalone name resolution, name based routing or hybrid of the two. With the essence of NRS, it is urgent to identify the requirements for the NRS design in ICN. In the draft, we propose the NRS requirements from the different aspects and elaborate each of them with examples for verification of its importance. We also discuss the use cases of NRS in the ICN literature. 9. References 9.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC7927] Kutscher, D., Ed., Eum, S., Pentikousis, K., Psaras, I., Corujo, D., Saucez, D., Schmidt, T., and M. Waehlisch, "Information-Centric Networking (ICN) Research Challenges", RFC 7927, DOI 10.17487/RFC7927, July 2016, . 9.2. Informative References [1] G. Xylomenos, C. N. Ververidis, V. A. Siris, N. Fotiou, C.Tsilopoulos, X. Vasilakos, K. V. Katsaros, and G. C. Polyzos, A Survey of Information-Centric Networking Research, Communications Surveys and Tutorials, Vol. 16, No. 2, 2014, pp. 1024-1049. [2] E. Baccelli, C. Mehlis, O. Hahm, T. Schmidt, and M. Wahlisch, Information Centric Networking in the IoT: Experiments with NDN in the Wild, in ACM ICN, 2014. Hong, et al. Expires September 14, 2017 [Page 18] Internet-Draft NRS Requirements March 2017 [3] Amadeo, M., Campolo, C., Iera, A., and A. Molinaro, Named data networking for IoT: An architectural perspective, in European Conference on Networks and Communications (EuCNC), 2014. [4] T. Koponen, M. Chawla, B. Chun, A. Ermolinskiy, K. H. Kim, S.Shenker, and I. Stoica, "A Data-Oriented (and Beyond) Network Architecture." in ACM SIGCOMM, 2007, pp. 181-192. [5] FP7 PURSUIT project. http://www.fp7-pursuit.eu/PursuitWeb/. [6] FP7 SAIL project. http://www.sail-project.eu/. [7] NSF Named Data Networking project. http://www.named-data.net/. [8] Content Centric Networking project. http://www.ccnx.org/. [9] NSF Mobility First project. http://mobilityfirst.winlab.rutgers.edu/. [10] V. Jacobson, D. K. Smetters, J. D. Thornton, M. F. Plass, N.H. Briggs, and R. L. Braynard, "Networking Named Content." in ACM CoNEXT, 2009. [11] A. Baid, T.Vu, and D. Raychaudhuri, "Comparing Alternative Approaches for Networking of Named Objects in the Future Internet." in IEEE Workshop on Emerging Design Choices in Name-Oriented Networking (NOMEN), 2012. [12] M. F. Bari, S. R. Chowdhury, R. Ahmed, R. Boutaba and B. Mathieu, "A Survey of Naming and Routing in Information- Centric Networks.", IEEE Communications Magazine, Vol. 50, No.12, P. 44-53. [13] J. Rajahalme, M. Sarela, K. Visala, and J. Riihijarvi, "On Name-based Inter-domain Routing," Computer Networks, vol. 55, no. 4, pp. 975-986, March 2011. [14] K. V. Katsaros, N. Fotiou, X. Vasilakos, C. N. Ververidis, C.Tsilopoulos, G. Xylomenos, and G. C. Polyzos, "On Inter- Domain Name Resolution for Information-Centric Networks," in Proc.IFIP-TC6 Networking Conference,2012. [15] Namespace Resolution in Future Internet Architectures, draft- wang-fia-namespace-01. [16] PID: A Generic Naming Schema for Information-centric Network, draft-zhang-icnrg-pid-naming-scheme-03. Hong, et al. Expires September 14, 2017 [Page 19] Internet-Draft NRS Requirements March 2017 [17] D. Zhang, H. Liu, Routing and Name Resolution in Information- Centric Networks, 22nd International Conference on Computer Communications and Networks (ICCCN), 2013. [18] S. Sevilla, P. Mahadevan, J. Garcia-Luna-Aceves, "iDNS: Enabling Information Centric Networking Through The DNS." Name Oriented Mobility (workshop co-located with Infocom 2014). [19] On the Naming and Binding of Network Destinations, https://tools.ietf.org/html/rfc1498. [20] oneM2M Functional Architecture TS 0001, http://www.onem2m.org/technical/published-documents. [21] Constrained RESTful Environments, CoRE, https://datatracker.ietf.org/wg/core/charter/, 2013. [22] RFC 7252, The Constrained Application Protocol (CoAP). [23] CoRE Resource Directory, https://datatracker.ietf.org/doc/draft-ietf-core-resource- directory/. [24] C. Westphal, E. Demirors, An IP-based Manifest Architecture for ICN, 2nd ACM Conference on Information-Centric Networking (ICN 2015). [25] M. Mosko, G. Scott , I. Solis , C. Wood, CCNx Manifest Specification, http://www.ccnx.org/pubs/draft-wood-icnrg- ccnxmanifests-00.html. [26] The Locator/ID Separation Protocol (LISP), https://datatracker.ietf.org/doc/rfc6830/. [27] Locator/ID Separation Protocol (LISP) Map-Server Interface, https://datatracker.ietf.org/doc/rfc6833/. [28] Ahlgren, B. et al., "A Survey of Information-Centric Networking", IEEE Communications Magazine vol. 50, no. 7, July 2012. [29] Xylomenos, G. et al., "A Survey of Information-Centric Networking Research", IEEE Communications Surveys and Tutorials vol. 16, no. 2, 2014. Hong, et al. Expires September 14, 2017 [Page 20] Internet-Draft NRS Requirements March 2017 [30] Baccelli, E., Mehlis, C., Hahm, O., Schmidt, T., and M. Wahlisch, "Information Centric Networking in the IoT: Experiments with NDN in the Wild", ACM ICN, September 2014. [31] Amadeo, M., Campolo, C., Iera, A., and A. Molinaro, "Named data networking for IoT: An architectural perspective", European Conference on Networks and Communications, July 2014. [32] Quevedo, J., Corujo, D., and R. Aguiar, "A case for ICN usage in IoT environments", IEEE GLOBECOM, 2014. [33] Amadeo, M. et al., "Information-centric networking for the internet of things: challenges and opportunities", IEEE Network vol. 30, no. 2, July 2016. [34] Zhang, Y. et al., "Requirements and Challenges for IoT over ICN", Internet Draft, draft-zhang-icnrg-icniotrequirements-01, April 2016. [35] Jung, H. et al., "IDNet: Beyond All-IP Network", ETRI Jouranl vol. 37, no. 5, October 2015. [36] Yu Zhang et al., "A Survey of Mobility Support in Named Data Networking," NOM 2016. [37] R. Ravindran et al., "Forwarding-Label support in CCN Protocol," IETF draft, March 2016. [38] Alexander Afanasyev et al., "SNAMP: Secure Namespace Mapping to Scale NDN Forwarding," IEEE Global Internet Symposium, April 2015. [39] Marc Mosko, "Nameless Objects," July 2015. Hong, et al. Expires September 14, 2017 [Page 21] Internet-Draft NRS Requirements March 2017 Authors' Addresses Jungha Hong ETRI 218 Gajeong-ro, Yuseung-Gu Daejeon 34129 Korea Phone: +82-42-860-0926 Email: jhong@etri.re.kr Lijun Dong Huawei Technologies 10180 Telesis Court Suite 220 San Diego, CA, 92121 Phone: Email: lijun.dong@huawei.com Tae-Wan You ETRI 218 Gajeong-ro, Yuseung-Gu Daejeon 34129 Korea Phone: +82-42-860-0642 Email: twyou@etri.re.kr Cedric Westphal Huawei Technologies 2330 Central Expressway Santa Clara, CA 95050 Phone: Email: cedric.westphal@huawei.com Yong-Geun Hong ETRI 218 Gajeong-ro, Yuseung-Gu Daejeon 34129 Korea Phone: +82-42-860-6557 Email: yghong@etri.re.kr Hong, et al. Expires September 14, 2017 [Page 22] Internet-Draft NRS Requirements March 2017 GQ Wang Huawei Technologies 2330 Central Expressway Santa Clara, CA 95050 Phone: Email: gq.wang@huawei.com Jianping Wang City University Hong Kong Phone: Email: jianwang@cityu.edu.hk Hong, et al. Expires September 14, 2017 [Page 23]