Internet DRAFT - draft-azgin-icnrg-ni
draft-azgin-icnrg-ni
ICN Research Group A. Azgin
Internet-Draft R. Ravindran
Intended status: Informational Huawei Technologies
Expires: January 18, 2018 July 17, 2017
Enabling Network Identifier (NI) in Information Centric Networks to
Support Optimized Forwarding
draft-azgin-icnrg-ni-02
Abstract
The objective of this proposal is to introduce the notion of network
identifier (NI) in the ICN architecture. This is in addition to the
existing names (i.e., content identifiers, CIs, or application
identifiers, AIs, in general) that are currently used for both naming
and routing/forwarding purposes. Network identifiers are needed
considering the requirements on future networking architectures such
as: (i) to support persistent names (or persistently named objects)
and large-scale and high-speed mobility of any network entity (i.e,
devices, services, and content), (ii) to accommodate different types
of Internet of Things (IoT) services, many of which require low-
latency performance, and enabling edge computing to support service
virtualization, which will require support for large scale migration
and replication of named resources, and (iii) to scale the ICN
architecture to future Internet scale considering the exponentially
increasing named entities. If information on AI-to-NI mappings are
not directly accessible to the consumers, for instance, using
specific datasets like manifests, these considerations may require
enabling a name resolution service, which can be network based or
application driven, to support efficient and scalable routing.
Current document do not impose any restrictions on the name
resolution architecture, regarding its scope.
In the current draft, we begin by highlighting the issues associated
with ICN networking when utilizing only the AIs, which include
persistently named content, services, and devices. Next we discuss
the function NI serves, and provide a discussion on the two current
NI-based proposals, along with their scope and functionalities. This
is with the objective of having a single NI construct for ICN that is
flexible enough to adapt to different networking contexts.
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 RFC 2119 [RFC2119].
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Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on January 18, 2018.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Application Identifier (AI) vs. Network Identifier (NI) in
ICN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. NI based ICN Forwarding . . . . . . . . . . . . . . . . . . . 7
3.1. Label based ICN forwarding . . . . . . . . . . . . . . . 8
3.2. Link-object based ICN forwarding . . . . . . . . . . . . 9
3.3. Link Object vs. Forwarding Label . . . . . . . . . . . . 10
4. Name Resolution System Considerations . . . . . . . . . . . . 12
5. Differences with respect to Existing IP-based Proposals . . . 13
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.1. Normative References . . . . . . . . . . . . . . . . . . 14
6.2. Informative References . . . . . . . . . . . . . . . . . 14
Appendix A. Additional Stuff . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
Information centric networking (ICN) is proposed as a future Internet
architecture to evolve the current host-centric design of Internet
towards a content-oriented one, where the named object becomes the
principle entity in networking. In doing so, contents, services, and
devices become disentangled from any particular host (or hosts)
allowing for efficient use of the distributed in-network caches and
compute resources with more flexible and dynamic packet forwarding
techniques. ICN is expected to offer a scalable and secure
networking solution to address many challenges of the current IP
architecture. Towards this, we propose to formalize the notion of
network identifier (NI) in ICN protocol, that is separate from
content name or application identifier (CI/AI, or simply AI) used to
both name resources and route user requests.
2. Application Identifier (AI) vs. Network Identifier (NI) in ICN
AI represents the names of services, contents, or devices assigned by
the application providers or device manufacturers, and which can be
validated through appropriate security mechanisms. AIs are
specifically used for content request and distribution. ICN should
provide flexibility in accommodating a broad set of identifiers,
within which the two well-known classes include hierarchical and flat
identifiers. While a hierarchical identifier provides contextual
richness for the names, a self-certified flat identifier offers a
fixed predictable overhead and context-based security features (as
they can be hash of the content object or hash of the public key).
Today, this identifier set is already in the order of billions (with
hundreds of millions domain name registrations across all top-level
domain names [VRSGN]). As tens of billions of devices are expected
to join the network, this identifier set will be further augmented
with the corresponding data objects significantly expanding its size.
To decouple applications from the underlying network dynamics,
identifiers are expected to be persistent within the scope of the
application and its deployment.
NI provides a binding for the AI to the network, at a location and in
a topology relevant manner. In more specific cases, such as with
anycast use of NIs or for multi-source-homing scenarios, binding can
target a set of locations rather than a single location. NI is
managed by the network provider to name the routers, point of
attachments, servers and end devices. In addition to ICN names, in
an overlay deployment, NI could assume names associated with the
underlay network as well, such as IP or Ethernet addresses, in which
case the NIs would be carried within the underlying protocol headers,
potentially with further address translations occurring at the ICN-
enabled routers, hosts, or devices. The growth in the NI space is
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proportional to the rate of growth in domain topology, the total
number of AS(s), and the end points (if they are managed by the
network), whereas the growth of the AI space is proportional to the
rate of growth of the named resources within it. Considering the
potential use cases for ICN, the growth in AI space can be expected
to be much faster than that of NI space. Furthermore, as NI is a
routing construct, which can be modified en-route using per-hop name
resolution at the domain boundaries, the forwarding table sizes at
the core routers can be limited to the number of AS(s) instead of the
size for the set of end points. Hence if the objective is to limit
the size of the forwarding table and scale control plane, it is
desirable to route requests on NIs, with the mapping between AI and
NI is achieved in a scalable manner using one of many ways including
but not limited to using a network based name resolution system or
using a manifest-driven information database system to provide such
mappings.
Content-centric design used by ICN allows end hosts to make requests
using any type of name supported by the applications, including
hierarchical (human-readable or hash-based) identifiers (as
considered by CCN, NDN[CCN] for both the client application use and
the network use-for routing-), or fixed flat identifiers (as
considered by MobilityFirst[MFRST] in the network for routing). We
refer to an ICN architecture that supports any application naming
format (i.e., human-readable or flat) within the network for routing
as a non-restricted ICN architecture (as in CCN/NDN), whereas an ICN
architecture with a fixed naming format for routing within the
network as a restricted ICN architecture (as in MobilityFirst).
As packet forwarding in ICN utilizes names or identifiers (associated
with contents, hosts, or services) which are typically managed by
applications, thereby of 'mostly' persistent nature, using such names
in packet forwarding introduces certain challenges in regards to
routing scalability and forwarding efficiency [NAMES]. Depending on
the application context, it is possible for an application to support
the use of non-persistent names, for instance, in the case of real-
time multimedia services, with further challenges towards achieving
scalable routing and efficient forwarding. We list the most critical
challenges with respect to use of names in routing as follows.
o Using AI for Routing/Forwarding: Assigning dual functions to an
application identifier to include using it as a locator may, in
certain scenarios and depending on the ICN implementation, lead to
unstable 'routing control and forwarding plane' operations,
particularly when replication and mobility of content or end
points are taken into consideration. Specifically, if application
identifiers are used in routing, we can express the update
overhead to be proportional to the multiplication of update-reach
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(i.e., the level of reachability of the update in terms of the
number of routers that need to update their routing/forwarding
tables), update-frequency, updated-object-count, which can easily
reach unmanageable levels, with shift towards more mobile
communications or higher level of content replication.
o Applications typically construct names and replicate contents or
services to optimize their delivery without any consideration
towards network scalability or efficiency. Accordingly, name
aggregation may not help with scaling the routing and forwarding
as typically considered [RFC7927], and the cost of this would be
quite significant in real world scenarios, as discussed in more
detail in [NCMP]. Furthermore, it is also observed in [QCMP]
that, in certain scenarios (such as content mobility), name-based
forwarding approaches can operate more efficiently, if used in
conjunction with address-assisted schemes such as DNS or anchor
point based approaches like Mobile IP [RFC3220]. Additionally,
when names are used for network reachability, more practical
problems such as name-suffix hole may arise, as the content
requests are forwarded towards non-existent caches [MDHT].
o Routing/Forwarding Scalability: Routing scalability is typically
achieved by designing routing state with aggregate-able property,
which is the case for the current IP architecture. However,
having such feature in a non-restricted ICN architecture would
lead to relinquishing the persistency of the names, along with its
security binding such as trust, as the names would involve a
topological component for scalability, which can also suggest
resources to be renamed depending on, for instance, network or
business specs or characteristics. Note that, routing on names
with aggregate-able property would mean that names need to change
as the location for name changes, for instance, with publisher/
producer mobility. As we assume that trust relationships are
established based on names, changing names would mean updating
security bindings accordingly, dynamically as requests are pushed
towards the content source.
o When content names or application identifiers use a hierarchical
identifier format, we observe scalability problems in control and
data plane operations [SFWD]. Such problems are caused by various
factors. For instance, the explosive growth observed in
namespaces can lead to a similar growth in routing/forwarding
information base or table sizes [AFWD][SPIT][WPIT], even when
namespace aggregation is enabled, to significantly limit the
forwarding efficiency and forwarding capacity. If ICN routing
with hierarchical naming is the accepted form of naming, name-
aggregation is highly unlikely to achieve any practical
scalability. This is because, naming ontology and assignment
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typically consider application objectives of contextualizing
names, service and content placement and replication to better
suit the consumers' needs without considering any network
objectives on control and data plane efficiency and scalability.
o Handling Mobility, Migration, and Replication: The impact of
namespace expansion on routing/forwarding performance is typically
exacerbated with content mobility, or the use of multi-homing and
resource replication due to diminished aggregate-ability [NCMP].
The authors in [QCMP] concludes that, as more than 20% of end
hosts make more than 10 network address transitions every day,
thereby suggesting that mobility should be considered as the norm
rather than the exception. Furthermore, to achieve location
independent routing based on AIs, each mobility event associated
with a device or a popular content may trigger updates on up to
14% of Internet routers.
For the above reasons, restructuring the identifier to directly or
indirectly contain a globally routable component becomes an important
requirement, especially, to handle mobility at the network layer for
architectures that do not restrict names or identifiers to any
specific format. We can refer to such operation as the Application
and Network identifier split (where the NI represents the globally
routable component, and the AI represents the persistent name/
identifier) which enables splitting of the namespace to support
routable, persistent, and human-friendly names or identifiers. In
such a framework, names would be divided accordingly, i.e., based on
application binding (offering persistent names) vs. advertised
network entities (in routing plane) to provide a more scalable
routing architecture. For instance, a persistent name or identifier
/Provider/Type/Name, which would be used to create secure content
objects, can be published by multiple content distributors, where it
would be mapped to different NIs, such as /Distributor/Region/Zone/
Storage, to resolve content names or identifiers to specific
infrastructure entities. The fundamental requirements with this form
of splitting is no different than that of MobilityFirst [MFRST] or
LISP [RFC6830], which is the requirement of a network based name
resolution system to map the two namespaces.
So far, various approaches have been proposed to support the use of
NI in ICN-based networking architectures, depending on how this
information is structured and where it is placed within the Interest
(which may also determine the structuring of Data packets). Next, we
discuss these solutions by specifically focusing on label-based ICN
forwarding [FWLDR][FWLRP][MAAS] and ICN-based Map-and-Encap
[MPNCP][SNAMP] to provide a general guidance on the use of NI in
information centric networks.
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3. NI based ICN Forwarding
AI based routing is a feasible solution within certain contexts such
as: (i) when resources are static and routing is limited to local
area networks or local domains, such as access networks within the
scalability considerations of the control and forwarding plane; (ii)
in ad hoc situations where AI can be combined with suitable suffix
filters to seek content of interest for the applications; (iii) in
infrastructure-less scenarios with limited scalability requirements.
On the other hand, the use of NI becomes important in the following
situations: (i) when the Interest packet goes outside the local
domain, where routing on AI is optionally supported (i.e., as routing
scalability and efficiency seeks precedence, forwarders can choose to
exclude certain AIs from FIB processing, which may limit the
forwarding of requests carrying such AIs); (ii) when the Interest
enters a local domain, and the domain has specific knowledge of an NI
associated with the resource inside its domain (as the use of NIs
would address routing efficiency through exact matching on the NI
rather than performing longest prefix matching on AIs). The first
situation can limit routability of requests if information on how to
reach an AI is not carried in all domains, whereas the second
situation, for various reasons, can help with efficient forwarding of
requests by routing on NIs rather than on AIs even though it is
supported (e.g., NI lookup may be performed on a more performance
efficient state table using exact match rather than longest prefix
matching).
With the above considerations, with respect to end-to-end networking,
using NI for routing is not a mandatory feature, but an optional one.
However, as significant amount of user traffic fetches resources
outside the requesting host's local domain, it becomes crucial to
provide architectural support for routing on NIs in an ICN protocol.
Here, we consider NI as an implemented feature for communication
among static network components (e.g., as router identifiers) or
cross domains (e.g., as domain identifiers or global identifiers),
and can be designed using locally or globally defined policies, which
for the latter case may require globally agreed semantics for trust
management to validate bindings between NIs and AIs.
So far, two solutions for NI in ICN, overall with the same objectives
but serving different purposes, have been proposed. These include
the forwarding-label proposal [FWLDR] and the Link Object described
in [SNAMP]. We next summarize these proposals and discuss their
differences.
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3.1. Label based ICN forwarding
Label-based ICN forwarding provides NI capability by encoding a
network address along with (optional) security binding attributes
within an Interest packet to guide it towards a content source (which
can be the Producer, a content repository or a cache). We refer to
this label that provide the NI capability as the forwarding label
[FWLDR], which can be offered as part of an ICN network service (such
as a name resolution service with ICN APIs to register and resolve
names). Security binding attributes are considered optional for
forwarding labels as their scope can be limited to use within a
domain, and within the boundaries of a domain, with an established
trust among forwarding hosts (i.e., network routers) such bindings
may not be needed. On the other hand, to ensure cross-domain
validity of forwarding labels, in the absence of prior established
trust relationships, security binding attributes are considered as
mandatory, and enforced at domain boundaries to ensure that end-to-
end NI-based packet forwarding is supported. There may be exceptions
to the above scenarios depending on how the NIs are utilized and
updated.
For the forwarding label, we have the following important
considerations: (i) forwarding label, if present in the Interest
packet, takes precedence (over AI) for routing to ensure consistency
in packet forwarding whenever its used is triggered (for instance, to
avoid the emergence of loops which can occur as a consequence of
alternating between routing on AIs and routing on forwarding labels),
(ii) forwarding label is mutable in the sense that it can be swapped
or removed by intermediate network elements in the network based on
routing considerations within its domain. Note that, to ensure
compatibility with future potential use cases, label based ICN
forwarding can also utilize dynamic precedence, for instance to
prevent routers from unnecessarily dropping requests. Here,
forwarding labels are not limited to only the ICN names, but, in an
overlay mode, they can also represent names from other transport
layers as well, for instance, an IP address or a MAC address.
Forwarding label consists of multiple components, one of which is the
NI that represents the locator information. If the AI namespace
supports the use of an NI to reach a specific destination, forwarding
label is embedded within the Interest message at the edge router or
the end point within certain trust considerations. For security
reasons, edge routers can validate the label, which is inserted by
the end hosts, based on the trust context. For instance, if the
inserted label cannot be validated, edge router can ignore the label
inserted by the end-host and swap it with a new one depending on the
feedback from the name resolution system; or if forwarding on labels
is not supported, edge router can ignore any such label inserted by
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an ICN forwarder at the end hosts, by simply removing the inserted
label. Such an approach requires no trust relationship among
different domains, as each domain is capable of resolving content
namespace to a target domain, and swapping the received label with
one to which its resolves.
Forwarding label support for a namespace can be offered at a global
scale (i.e., supported by all the domains) or a local scale
(supported by a subset of the existing domains). For instance, some
autonomous systems can prioritize forwarding solely based on the
content names (or offer limited support for label-based forwarding on
specific namespaces). In such case, forwarding labels can include
additional service tag (or information on the associated service, for
which the use of forwarding label might be supported in certain
domains, such as towards mobility service) for routing packets on the
supported domains. In doing so, we can strategically forward
requests over domains that support such service to provide more
deterministic service guarantees.
If forwarding label use is supported (or permitted) within a domain,
by default, forwarding label is given preference over content
identifiers for packet forwarding. In such case, to maximize the
forwarding efficiency, additional mapping tables can be implemented
at the edge or border ICN routers for quick longest-prefix matching
(LPM) lookup on content names to determine a (or the) matching
forwarding label(s), which can then be used by the router to perform
LPM lookup on the FIB. As forwarding label typically represents a
target domain or router, a single LPM lookup on the FIB may suffice
to find the outgoing interface for the received Interest. This state
can also be software-defined based on application requirements using
an SDN based control plane.
3.2. Link-object based ICN forwarding
ICN-based Map-and-Encap [SNAMP] utilizes link objects, which include
information on how to retrieve content objects. For instance, link
objects can represent domains that host the content object, or
direction towards which the requests need to be forwarded to find a
matching content object. Link objects consist of two optional
headers: (i) a link header, which includes the potential directives
that can be used for forwarding and is signed by the Producer to
validate its authenticity during forwarding, and (ii) a delegation
header, which is used to represent the link choice utilized by the
previous forwarder. Since delegations may change at consecutive hops
depending on the view of forwarders' network state and forwarding
strategy, delegation header represents a variable component that can
be altered during packet forwarding.
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The role of link objects is mainly for guidance, to provide global
routing support on locally defined or routable content identifiers.
Hence, if link objects are implemented, they are consulted by the ICN
enabled routers only when forwarding lookup on content identifiers
returns no match on the forwarding information base.
3.3. Link Object vs. Forwarding Label
Next we list the major differences between a link object and a
forwarding label.
o Link objects are set by the end host's forwarding daemon with
certain level of trust associated to it, restricting the link
component to be immutable during forwarding. Forwarding labels
are initially set by the ICN edge routers or the end-host
applications and allow mutable operation through late-binding
during Interest forwarding. In doing so, forwarding label offers
the ability of network based management during Interest
forwarding, which allows each domain to perform packet forwarding
according to its administrative and service policies. Note that,
it is possible for link objects to trigger network based
management operations, however their impact would be limited, in
the worst case triggering NACKs that may prevent the use of link
objects to help with forwarding.
o Link objects constrain a network operator from overriding a
consumer's intent, which, in some cases, may potentially lead to
better performance compared to forwarding over native network
service provider paths. Forwarding labels require additional
mechanisms to support such feature, for instance, to enable the
desired path for the consumer, which may necessitate the use of
additional forwarding labels within requests.
o For the link objects, security binding is mandatory and trust
relationship is established by default, by putting all the trust
assessment at the end hosts. On the other hand, security binding
is optional for the forwarding label, which allows the use of
trust association to bind AI to the NI depending on the context
associated with its use. However, without appropriate support in
trust management, forwarding label use may introduce problems such
as route hijacking, hence contextual management should be capable
of addressing such challenges using, for instance, approaches
identified in [FWLDR].
o Another difference is related to the processing of forwarding
labels and link objects at the ICN routers. A link object is
processed only if the router cannot find a matching FIB entry for
the content identifier limiting routing flexibility. Furthermore,
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if no matching FIB entry is found, link objects would trigger
additional lookups on the FIB, leading to efficiency issues with
frequent occurrences. On the other hand, forwarding label is
processed before a content identifier, if its use is enabled,
hence presents a more flexible and efficient operation in routing.
o Link object can be considered as a hint towards where to find the
content, and since it is processed after FIB lookup on the content
identifier fails, it typically leads to lower computational and
bandwidth efficiency. Forwarding label, on the other hand, can be
considered as an enabler for faster packet processing at the ICN
routers as it allows bypassing content/application identifier
based processing at the supported routers, while at the same
offering optimized routing towards a content source.
o Link object is considered as an application driven component and
network service agnostic, thereby allowing the network to decide
on its use. Forwarding label, on the other hand, can be enabled
as part of a service, which limits the use of forwarding label to
the supported namespaces, while at the same time requiring its use
whenever/wherever supported. For instance, within the context of
virtualizing the ICN network among multiple services, where
compute, storage, and bandwidth resources are shared among these
services, ICN service edge routers can apply rules on namespaces
to decide on how to dedicate network resources. One example of
such service is the mobility service, which can utilize forwarding
labels, to provide stricter service quality guarantees for the end
hosts. In such case, if the namespace requires mobility support,
forwarding label is used in effect to achieve more efficient
forwarding. Note that, service use can be triggered with the use
of service tags integrated within forwarding labels, once
validated to be used with the corresponding namespace(s).
o As a link object can encode multiple routing hints, it can direct
a request towards multiple identifier locations, giving an ICN
router the option to choose any one of them based on the router's
forwarding strategy. Even though this selection is shared between
consecutive routers, it is not enforced, thereby potentially
leading to non-optimal forwarding paths. Forwarding label, on the
other hand, is enforced consistently at consecutive hops within a
domain whenever/wherever its use is supported and/or enabled.
Hence, forwarding label presents the network with the ability to
consistently forward packets over optimal paths towards a content
source (with respect to routers forwarding the requests towards
the same direction, rather than choosing alternating
destinations).
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4. Name Resolution System Considerations
To manage the AI to NI mapping, we need a name resolution system
(NRS). In addition to exposing APIs to application to register its
name to the NRS, it should also scale and work efficiently
considering the scale of named resources that need to be published,
resolved, removed, and updated at high frequency, for instance,
corresponding to high-speed mobility scenarios.
The following are the design choices for the NRS:
o Hierarchical System: Here, AI to NI mapping is managed by the
application providers, but similar to DNS, the service has to sync
its name reachability information with high level name resolvers.
NDN-DNS (NDNS) is an example of such a system [NDNS], which
utilizes a zone-based hierarchy (i.e., root level, top-level
domain, etc.) and which is queried iteratively at every component
level of the content/application identifier (e.g., /tld/sld would
trigger iterative requests of /dns/tld/NS and /dns/sld/NS, at the
root and tld levels). NDNS also supports recursive queries to
scope the route requests for a content/application identifier.
Even though the design of NDNS supports forwarding of Interests on
content/application identifiers not present in the FIB, its design
is typically suitable in cases when resources are static, rather
than for highly dynamic systems such as ICN, where replication and
mobility will be the norm. Supporting mobility in NDNS may
require frequent updates and requests to setup and identify routes
towards mobile entities, which may lead to performance-related
problems. Also, such system has to scale to resolve not just the
end hosts, which represents the current use, but also the
information objects.
o Network-Integrated Flat System: Here, resolution service is
integrated within the ICN infrastructure, where the router
contributes a part of its compute and storage resources to enable
this service. This integration allows multiple ways of designing
a generic name resolution service, similar to the overlaid or in-
network designs considered for Global Name Resolution Service
(GNRS) in MobilityFirst [GNS] [ASPC] [GNRS] allowing for good
scalability performance with proven handling of dynamic updates,
aided by a separation of entity identifiers from network
identifiers. In GNRS, flat names are queried to obtain the
corresponding self-certifying identifiers, such as the network
address, before forwarding an Interest for the flat globally-
unique identifier.
o Distributed System: Compared to a flat resolution system, this
type of architecture preserves the contextual nature of DNS, by
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using the context in the content identifier (such as the network
or host identifier portion of the name) to identify a resolution
server corresponding to the context information, such as home
controller, which stores the mappings associated with registered
names carrying the controller's context information and where the
respective AI to NI mapping can be resolved. Such a system
removes the need for the home controllers to sync up with high
level resolvers, as for successful resolution it is sufficient for
each controller to manage the names registered to or under it.
For instance, /company/content-id would be mapped with a local
resolver, identified with /company/resolver-id, that manages any
namespace registered under its domain identifier (/company). In
doing so, content mobility can effectively be handled through
localized updates (for intra-domain mobility) or remote updates at
the home controller (for inter-domain mobility) with minimal
signaling overhead, while maintaining global scalability.
5. Differences with respect to Existing IP-based Proposals
To address persistent identity, routing scalability, multihoming, and
mobility limitations of the current IP, various incremental solutions
have been proposed, among which identifier/locator split emerged as
the key solution to address these challenges [RFC4984]. Here, we
specifically focus on three of these solutions: (i) Host Identity
Protocol (HIP) [HIP], (ii) Identifier-Locator Network Protocol (ILNP)
[ILNP], and Locator/Identifier Seperation Protocol (LISP) [RFC6830].
HIP and ILNP achieve ID/locator separation and binding at the host
level whereas LISP achieves that at the network level (i.e., at the
network edge using service routers).
In HIP, public cryptographic keys are used as host identifiers, which
provide the binding to higher layer protocols instead of IP addresses
[RFC7401]. ILNP divides IP namespace into two distinct namespaces of
identifiers and locators, each of which carrying distinct semantics
with identifier representing the non-topological name for the host
and locator representing the topologically bound name for the network
[RFC6740]. LISP is a map-and-encap type protocol, which achieves id/
locator separation by defining (i) endpoint identifiers, which are
used for routing at the access network and which represent the IP
address for the host, and (ii) routing locators, which are used for
routing at the core and which represent the IP address for the egress
routers.
These protocols fundamentally differ from ICN's objective to define a
new network layer, where name based routing, location independent
caching, mobility, multihoming, and multi-path routing are the
integral features. More specifically, this draft proposes to enable
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AI/NI binding as a network service to allow efficient routing of user
requests depending on the application context.
6. References
6.1. 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,
<http://www.rfc-editor.org/info/rfc2119>.
6.2. Informative References
[AFWD] Yi, C., Afanasyev, A., Wang, L., Zhang, B., and L. Zhang,
"Adaptive Forwarding in Named Data Networking", ACM CCR,
Jul 2012.
[ASPC] Sharma, A., Tie, X., Uppal, H., Venkataramani, A.,
Westbrook, D., and A. Yadav, "A Global Name Service for a
Highly Mobile Internetwork", ACM SIGGCOM, 2014.
[CCN] Jacobson, V., Smetters, D., Thornton, J., Plass, M.,
Briggs, N., and R. Braynard, "Networking Named Content",
ACM CoNEXT, 2009.
[FWLDR] Ravindran, R., Chakraborti, A., and A. Azgin, "Forwarding
Label Support in CCN Protocol", draft-ravi-icnrg-ccn-
forwarding-label-01, July, 2017.
[FWLRP] Azgin, A., Ravindran, R., and G. Wang, "A Scalable
Mobility-Centric Architecture for Named Data Networking",
IEEE ICCCN Scene Workshop, 2014.
[GNRS] Hu, Y., Yates, R., and D. Raychaudhuri, "A Hierarchically
Aggregated In-Network Global Name Resolution Service for
the Mobile Internet".
[GNS] Venkataramani, A., Sharma, A., Tie, X., Uppal, H.,
Westbrook, D., Kurose, J., and D. Raychaudhuri, "Design
Requirements for a Global Name Service for a Mobility-
Centric, Trustworthy Internetwork", IEEE COMSNETS, 2013.
[HIP] Nikander, P., Gurtov, A., and T. Henderson, "Host identity
protocol (HIP): Connectivity, mobility, multi-homing,
security, and privacy over IPv4 and IPv6 networks", IEEE
Communications Surveys and Tutorials, pp: 186-204, 2010.
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[ILNP] Atkinson, R., "An Overview of the Identifier-Locator
Network Protocol (ILNP)", Technical Report, University
College London, 2005.
[MAAS] Azgin, A., Ravindran, R., Chakraborti, A., and G. Wang,
"Seamless Producer Mobility as a Service in Information
Centric Networks", ACM ICN IC5G Workshop, 2016.
[MDHT] Liu, H., Foy, X., and D. Zhang, "A Multi-level DHT routing
Framework with Aggregation", ACM SIGCOMM ICN Workshop,
2012.
[MFRST] Venkataramani, A., Kurose, J., Raychaudhuri, D., Nagaraja,
K., Mao, M., and S. Banerjee, "MobilityFirst: A Mobility-
centric and Trustworthy Internet Architecture", ACM
SIGCOMM CCR, 2014.
[MPNCP] Afanasyev, A., Yi, C., Wang, L., Zhang, B., and L. Zhang,
"Map-and-Encap for Scaling NDN Routing", NDN Technical
Report, ndn-004-02, 2015.
[NAMES] Baid, A., Vu, T., and D. Raychaudhuri, "Comparing
Alternative Approaches for Networking of Named Objects in
the Future Internet", IEEE INFOCOM NOMEN Workshop, 2012.
[NCMP] Adhatarao, S., Chen, J., Arumaithurai, M., Fu, X., and K.
Ramakrishnan, "Comparison of Naming Schema in ICN", IEEE
LANMAN, 2016.
[NDNS] Afanasyev, A., "Addressing Operational Challenges in Named
Data Networking Through NDNS Distributed Database", 2013.
[QCMP] Gao, Z., Venkataramani, A., Kurose, J., and S. Heimlicher,
"Towards a Quantitative Comparison of Location-Independent
Network Architectures", ACM SIGCOMM, 2014.
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
DOI 10.17487/RFC2629, June 1999,
<http://www.rfc-editor.org/info/rfc2629>.
[RFC3220] Perkins, C., "IP Mobility Support for IPv4", RFC 3220,
2002.
[RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC
Text on Security Considerations", BCP 72, RFC 3552,
DOI 10.17487/RFC3552, July 2003,
<http://www.rfc-editor.org/info/rfc3552>.
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Internet-Draft ICN-NI July 2017
[RFC4984] Meyer, D., Zhang, L., and K. Fall, "Report from the IAB
Workshop on Routing and Addressing", RFC 4984, 2007.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226,
DOI 10.17487/RFC5226, May 2008,
<http://www.rfc-editor.org/info/rfc5226>.
[RFC6740] Atkinson, R. and S. Bhatti, "Identifier-Locator Network
Protocol (ILNP) Architectural Description", RFC 6740,
2012.
[RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The
Locator/ID Separation Protocol (LISP)", RFC 6830, 2013.
[RFC7401] Moskowitz, R., Heer, T., Jokela, P., and T. Henderson,
"Host Identity Protocol Version 2 (HIPv2)", RFC 7401,
2015.
[RFC7927] Kutscher, D., Eum, S., Pentikousis, K., Psaras, I.,
Corujo, D., Saucez, D., Schmidt, T., and M. Waehlisc,
"Information-Centric Networking (ICN) Research
Challenges", RFC 7927, 2016.
[SFWD] Yuan, H., Song, T., and P. Crowley, "Scalable NDN
Forwarding: Concepts, Issues and Principles", IEEE ICCCN,
2012.
[SNAMP] Afanasyev, A., Yi, C., Wang, L., Zhang, B., and L. Zhang,
"SNAMP: Secure Namespace Mapping to Scale NDN Forwarding",
IEEE Global Internet Symposium, 2015.
[SPIT] Yuan, H. and P. Crowley, "Scalable Pending Interest
Table Design: From Principles to Practice", IEEE INFOCOM,
2014.
[VRSGN] "Verisign Domain Name Industry Brief", July 2016.
[WPIT] Varvello, M., Perino, D., and L. Linguaglossa, "On the
Design and Implementation of a Wire-speed Pending Interest
Table", IEEE INFOCOM NOMEN Workshop, 2013.
Appendix A. Additional Stuff
This becomes an Appendix.
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Authors' Addresses
Aytac Azgin
Huawei Technologies
Santa Clara, CA 95050
USA
Email: aytac.azgin@huawei.com
Ravishankar Ravindran
Huawei Technologies
Santa Clara, CA 95050
USA
Email: ravi.ravindran@huawei.com
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