One document matched: draft-lee-object-naming-01.txt
Differences from draft-lee-object-naming-00.txt
HIP Working Group Gyu Myoung Lee
Internet Draft TELECOM SudParis
Intended status: Informational Jun Kyun Choi
Expires: April 2010 KAIST
Seng Kyoun Jo
Jeong Yun Kim
ETRI
Noel Crespi
TELECOM SudParis
October 26, 2009
Naming Architecture for Object to Object Communications
draft-lee-object-naming-01.txt
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Abstract
This document explains the concept of object to object communications
and describes naming issues for object identification. In order to
develop protocols for object to object communications, this document
provides the naming architecture according to mapping relationships
between host and object(s). In addition, considerations of protocols
for naming object are specified.
Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119.
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Table of Contents
1. Introduction.................................................5
2. Object to Object Communications..............................5
2.1. Definition of object....................................5
2.2. Concept of object to object communications..............6
2.3. Various types of objects................................6
3. Object Identification........................................7
3.1. Classification of network entities to be identified.....7
3.2. Identification codes....................................8
3.3. Examples of IDs for objects.............................8
3.3.1. RFID...............................................8
3.3.2. Content ID.........................................9
3.4. Requirements for naming using object identification.....9
4. Naming Architecture for Objects..............................9
4.1. Layered architecture for identity processing............9
4.2. The mapping relationships between host and object(s)...11
4.2.1. Host = Object (one to one mapping)................11
4.2.2. Host =! Object (one to many mapping)..............11
4.3. The stack architecture.................................11
4.4. Object mapping schemes.................................12
4.5. Providing connectivity to objects......................15
5. Considerations of Protocols for Naming Objects..............16
5.1. Security association...................................16
5.2. Support of DNS.........................................16
5.3. Protocol overhead......................................16
5.4. Common identifier for object...........................16
5.5. Specific user cases....................................16
5.6. Services using naming objects..........................17
6. Protocol operations and procedures..........................18
6.1. HIP basic operation (an example).......................18
6.2. Protocol procedures....................................18
7. Security Considerations.....................................19
8. IANA Considerations.........................................19
9. References..................................................19
9.1. Normative References...................................19
9.2. Informative References.................................20
Author's Addresses.............................................20
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1. Introduction
The one of new capabilities for future network will be the ubiquitous
networking such as the Internet of things. This networking capability
requires "Any Services, Any Time, Any Where and Any Devices"
operation. In order to connect objects (e.g., devices and/or
machines) to large databases and networks, a simple, unobtrusive and
cost-effective system of item identification is crucial. The concept
of host should be extended to support all of objects. However, there
is no consideration for new type of objects (e.g., contents, RFID
tags, sensors, etc) as end points.
This document explains object to object communications. For
identification of network entities, we consider new type of
identifiers (e.g., RFID code, content ID, etc) for object and
describe specific requirements for object identification in naming
point of view.
Architectural aspect, this document shows architecture for identity
processing and mapping relationship between several identities with
conceptual diagram for providing connectivity to objects.
According to several alternative architectures for object naming,
this document aims to provide requirements and right direction for
protocol development for realization of object to object
communications.
2. Object to Object Communications
2.1. Definition of object
An object means a model of an entity. An object is characterized by
its behaviour. An object is distinct from any other object. An object
interacts with its environment including other objects at its
interaction points. An object is informally said to perform functions
and offer services (an object which makes a function available is
said to offer a service). For modelling purposes, these functions and
services are specified in terms of the behaviour of the object and of
its interfaces. An object can perform more than one function. A
function can be performed by the cooperation of several objects.
NOTE: Objects include terminal devices (e.g. used by a person to
access the network such as mobile phones, Personal computers, etc),
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remote monitoring devices (e.g. cameras, sensors, etc), information
devices (e.g. content delivery server), products, contents, and
resources.
NOTE: The above definition was quoted from ITU-T [Y.2002].
2.2. Concept of object to object communications
For ubiquitous networking [Y.2002], future network will require the
extensions of networking functionalities to all objects. New
networking concept will be considered for networking capabilities to
support various classes of applications/services which require "Any
Services, Any Time, Any Where and Any Devices" operation using
Internet. This networking capability should support human-to-human,
human-to-object (e.g., device and/or machine) and object-to-object
communications.
2.3. Various types of objects
There are many different kinds of devices connecting to the network
supported for ubiquitous networking in Internet. RFID tag, sensors,
smart cards, medical devices, navigation devices, vehicles as well as
the existing personal devices such as PC, Personal Digital Assistant
(PDA), etc., are examples of these. This document considers that the
end points which are not always humans but may be objects such as
devices /machines, and then expanding to small objects and parts of
objects.
The object means that the user or other entity which is connected to
the network. It includes almost everything around us such as remote
monitoring and information device/machine/content, etc.
Figure 1 shows the connection of Internet with the relationship
between humans and objects in terms of identification and location in
specifically mobile environments. The types of objects in end-user
side include the following: personal devices, information devices,
RFID/sensors, contents, appliances, vehicles, etc.
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Objects
+-------------------------------------+
| +--------------+ |
| | +---------+ | +--------------+ |
| | |Personal | | | Contents | |
| | |Devices | | | | |
| | +---------+ | +--------------+ |
| H | | | Providing -------
| u | +---------+ | +--------------+ | Connectivity / \
| m | |Info. | | | Appliances | | | |
| a | |Devices | | | | |-------------- | Internet |
| n | +---------+ | +--------------+ | | |
| | | | | |
| | +---------+ | +--------------+ | | |
| | |RFID/ | | |Transportation | | \ /
| | |Sensors | | | | | -------
| | +---------+ | +--------------+ |
| +--------------+ |
+-------------------------------------+
Figure 1 Communications with objects through Internet
3. Object Identification
3.1. Classification of network entities to be identified
There are several network entities to be identified in the network.
These network entities have a layered architecture and are used for
naming, addressing and routing.
o Services (i.e., information related to applications/services)
o End points (i.e., global unique identifier)
o Location (i.e., IP address)
o Path (i.e., routing)
In particular, for object to object communications, information for
several kinds of object on top of end points should be identified in
the network.
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3.2. Identification codes
Identification of all objects for providing end-to-end connectivity
in ubiquitous networking environment is crucial. Identifier is
capable of identifying all objects and facilitates objects-to-objects
communications. In particular, the globally unique identifier enables
a lot of applications including item tracking, access control, and
protection, etc [1].
There are many kinds of identifiers such as E.164 number code,
Extended Unique Identifier (EUI)-64, Media Access Control (MAC)
address, Uniform Resource Identifier (URI)/ Uniform Resource Locator
(URL), etc.
These identification codes can be classified as follows.
o Object IDs: include RFID, Content ID, telephone number, URL/URI,
etc
o Communication IDs: include session/protocol ID, IP address, MAC
address, etc
In this document basically consider an "Object ID" which generally
takes the form of an application-specific integer or pointer that
uniquely identifies an object.
3.3. Examples of IDs for objects
3.3.1. RFID
The identification codes, so-called Electronic Product Code (EPC),
for RFID/sensors are very important in ubiquitous networking
environment. An EPC is simply a number assigned to an RFID tag
representative of an actual electronic product code. Their value is
that they have been carefully characterized and categorized to embed
certain meanings within their structure. Each number is encoded with
a header, identifying the particular EPC version used for coding the
entire EPC number. An EPC manager number is defined, allowing
individual companies or organizations to be uniquely identified; an
object class number is present, identifying objects used within this
organization, such as product types. Finally, a serial number is
characterized, allowing the unique identification of each individual
object tagged by the organization [2].
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3.3.2. Content ID
The Content ID is a unique identifier that can specify and
distinguish any kind of digital content that is distributed. As a
unique code attached to a content object, the Content ID serves well
enough as an identifier, but actually it is much more than just that.
It is also the key to a complete set of attribute information about a
content object stored as metadata including the nature of the
contents, rights-related information, information about distribution,
and more. The Content ID provides the key enabling metadata to be
uniquely associated with a particular digital object [3].
3.4. Requirements for naming using object identification
For object to object communications, how to map/bind IP address (i.e.,
communications IDs) with other identifiers (i.e., object IDs) for
providing end-to-end IP connectivity is challenging issue.
Additionally, the following features should be provided using naming
capability through object identification.
o Scalability with enough name space to support new devices/machines
enabling communications
o Protection of object (including right management)using security
function
o Connecting to anything for providing the connectivity to end
device without additional equipment such as Network Address
Translator using object identification
o Service and location discovery through performing two functions;
Routing using network prefix information and identification code
using object IDs
4. Naming Architecture for Objects
4.1. Layered architecture for identity processing
As shown in Figure 2, the layered architecture of identity processing
requires specific processing capabilities at each layer. Each
user/object in applications identifies by identity like name with a
set of attributes of an entity. An attribute can be thought of as
metadata that belongs to a specific entity in a specific context,
some of which could to be highly private or sensitive. The identity
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should be associated with object IDs through identification and
authorization. Each object ID also should be associated with
communication IDs through mapping/binding [Y.ipv6-object].
Identity Processing
Identifiers
------------ +-----------------+
+ User Name + |Logical identities |
+ (Attributes) + | for services |
+ + | |
------------ +-----------------+
^ |
| +---------------+ |
----- |----- |Identification/ |---------------- |-----------
| |Authorization | |
| +---------------+ |
| |
------------- +------------------+
+ Object IDs + | RFID,Content ID, |
+ (Physical & + |Telephone number, |
+ logical IDs) + | URL/URI, etc |
------------- +------------------+
^ |
| +---------------+ |
----- |----- | Mapping/ |---------------- |-----------
| | Binding | |
| +---------------+ |
| +---------------------+
| | Session/Protocol ID |
| +---------------------+
| |
+---------------------+
-------------- | IP address |
+ Communication + +---------------------+
+ IDs + |
+ + +---------------------+
-------------- | MAC address |
+---------------------+
Figure 2 Layered architecture for identity processing
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4.2. The mapping relationships between host and object(s)
In this document, host means a device that communicates using the
Internet protocols (i.e., IP addresses).
4.2.1. Host = Object (one to one mapping)
In case of a host is equal to an object, there is one to one mapping
relationship between host and object. Most of information devices
such as PC, etc are included in this case.
For example, if you use a telephone device, the device as host can be
allocated a telephone number as object ID and be treated the same
object.
4.2.2. Host =! Object (one to many mapping)
In case of a host is not equal to an object, there is one to many
mapping relationship between host and object(s). Content server, RFID
tags/Reader, etc are included in this case.
There are two kinds of one to many mapping as follows (see Figure 2):
o As shown in Figure 3 (a), host including objects such as content
server, a host includes many objects and these objects should be
identified using content ID, etc.
o As shown in Figure 3 (b), host with remote objects such as RFID
tags, a host has many remote objects and these objects should be
identified using RFID code, etc. In this case, each object might
be non IP.
4.3. The stack architecture
The original stack architecture of HIP can be extended according to
the mapping relationships between host and object(s).
o As shown in Figure 4 (a), objects in a host (case #1), the end
point is the same with current HIP architecture. However, each
object in service layer should be identified by a host using
mapping protocol for object.
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o As shown in Figure 4 (b), remote objects (case #2), the end point
will be each object. This means that host location is different
from end point(s). Thus, current HIP should be extended to support
several end points with a host. From object information in service
layer, each object identity should be defined.
4.4. Object mapping schemes
There are two kinds of object mapping schemes using one to many
mapping relationship as follows:
o Direct mapping (Figure 4 (a))
An object at application layer is directly reachable to host
entity at network attachment point which IP is terminated. An
object is located on top of TCP/IP protocol stack. For example,
host including objects such as content server, a host includes
many objects and these objects should be identified using content
ID, etc.
o Indirect mapping (Figure 4 (b))
An object at application layer is remotely reachable through non-
IP interface to host entity at network attachment point which IP
is terminated. An object is located outside of physical network
attachment which IP is terminated. For example, host with remote
objects such as RFID tags, a host has many remote objects and
these objects should be identified using RFID code, etc. In this
case, each object might be non IP.
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+--------------------------+
| |
| +--------+ |
| | Object | |
| +--------+ |
| |
| +--------+ |
| | Object | |
| +--------+ |
| . |
| . |
| . |
| |
| +--------+ |
| | Object | |
| +--------+ |
| |
| Host |
| |
+--------------------------+
(a) Host including objects(e.g., content server)
+-------+
-----------------| Object |
/ +--------+
/ .
/ .
+------+ +--------+
| Host | ------------------ | Object |
+------+ +--------+
\ .
\ .
\ +--------+
----------------| Object |
+-------+
Remote objects
(non IP)
(b) Host with remote objects(e.g., RFID tags/Reader)
Figure 3 Mapping between host (IP address) and objects (object IDs)
(one to many mapping)
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Host (e.g., content server)
+----------------------------+
| +----+ |
| | | Object IDs |
| +----+ |
| | |
| +----+ |
| | | IP address |
| +----+ |
| | |
| +----+ |
| | | Network |
| +----+ attachment |
+----------------------------+
IP interface |
-----------------------+
(a) Case #1: Objects in a host (host location = end points)
Object IDs
+----+
| |
Host (e.g., RFID reader) +----+
+---------------------------+ |
| | |
| +----+ | |
| | | IP address | |
| +----+ | |
| | | |
| +----+ | |
| | | Network | |
| +----+ attachment | |
+---------------------------+ |
IP interface | | non-IP interface |
---------------------+ +-------------------------+
(b) Case #2: Remote objects (host location =! end points)
Figure 4 Extension of stack architecture
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4.5. Providing connectivity to objects
For providing connectivity to objects using object identification,
the Figure 5 shows object mapping/ binding with IP address for IP
connectivity to all objects in end-user side. This scheme can provide
the global connectivity with NGN to objects through the association
(e.g., mapping/binding) between identifier for object and IP address.
Host(e.g., server)
|----------Object(e.g.,content)
+---------------|--------------+
| +-----------|-------+ |
| | +--|-+ | | IP address
| | | +----------| | | ********************
| | +----+ | ****| | | * *
| | +----+ | * |--- | * *
| | | +--------------* |---------------|------* *
| | +----+ | ****| | * *
| | +----+ | / | | * *
| | | |-------/ | | * *
| | +----+ | | | * *
| +-------------------+ | | * *
+------------------------------+ | * *
Object(e.g.,device, product, sensor,etc) | * Internet *
| | * *
+---|------------+ Gateway | * *
| | +----+ | | | * *
| |---| | | Non-IP | | * *
| +----+ | interface | | * *
| +----+ | | +----|-+ | * *
| | |---------|-----|---|--****| | * *
| +----+ |-----|---| * |------------|------* *
| +----+ | | |-|--**|*| | * *
| | |-----------| +--|-|-+ | * *
| +----+ | | | | ********************
| +----+ | |--| | IP interface
| | |---------|---------| |
| +----+ | IP address
+----------------+
+------------+ Mapping +-----------+ *****************
+ Identifier + <---------> + IP + ====> * Global *
+ for object + Binding + Address + * Connectivity *
+------------+ +-----------+ * with Internet *
*****************
Figure 5 Conceptual diagram for providing connectivity to objects
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5. Considerations of Protocols for Naming Objects
5.1. Security association
It is critical to provide security association for secure binding
between object identity and IP address similar with HIP [4].
5.2. Support of DNS
An ID resolution server such as Domain Name System (DNS), can provide
a function to translate the identifier of object into service
/communication ID to access networking services provided by
database/application servers.
In order to support from existing infrastructure, including DNS, it
is required to define DNS resource records. The newly defined DNS
resource records should include information on object IDs.
5.3. Protocol overhead
Real time communications and some limitation of power and packet size,
lightweight identity handshake for datagram transactions is critical.
5.4. Common identifier for object
Most of identifiers for object specified with different format
according to applications. However, in order to contain information
of all objects in HIP message and interoperate globally, it is
required to specify common identifier and rules to accommodate all
objects with unified format.
5.5. Specific user cases
HIP for object can use original advantages of HIP for specific user
cases.
o Identity-based roaming and mobility
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o Hierarchical routing
o Addressing and location management
o Multi-homing
o Rendezvous service (or mechanism)
o DNS service
5.6. Services using naming objects
The proposed naming objects can provide an integrated solution for
personal location and management through identification /naming
/addressing including ID registration, location tracking, dynamic
mobility control, and security using the following networking
services:
o Identity management (IdM) services for the management of the
identity life cycle of objects including managing unique IDs,
attributes, credentials, entitlements to consistently enforce
business and security policies.
o Location management services for real-time location tracking,
monitoring, and information processing of moving objects similar
with Supply Chain Management.
o Networked ID (N-ID) services for providing communication service
which is triggered by an identification process started via
reading an identifier from identifier storage such as RFID tag,
barcode label, smartcard, etc.
o Home networking services for the management of multiple object
identities in a host and/or remote host using RFID tag, ubiquitous
sensor, etc.
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6. Protocol operations and procedures
6.1. HIP basic operation (an example)
o In case of communications using RFID reader/tags, HIP Initiator
can be a RFID reader which is connected to a RFID tag (object)
using air interface and HIP Responder can be the information
server which stores all information of RFID tags. And then, if
this information server has a role of HIP rendezvous server, a
client can get binding information between Host (HIP Initiator)and
an object behind RFID reader for reachability to object(S) as end
point(s).
o The RFID reader has one-to-many mapping relationship. So, a host
identity of RFID reader maps onto many object identities.
o For IPsec security associations, HIP will definitely be terminated
at the RFID reader because HIP should be tightly coupled with
network layer. Similar with objects inside server, although each
object is located remotely through air interface with RFID reader,
we would like to consider RFID reader and tag as the same node
virtually.
o In this case, we need to find possible solutions.
NOTE: The related solutions will be provided later.
6.2. Protocol procedures
We illustrate the basic protocol procedure of sending a data packet
to an object and mappings/bindings that are involved as shown in
Figure 6:
o Find a node on which the required object resides. This requires
finding object and end point through object ID registration. Name
resolution using DNS is optionally required.
o Find a network attachment point to which the node is connected.
This requires finding location. For this, a client gets binding
information of object ID and IP address.
o Find a path from the client to object(s). The client can reachable
to object(s) using routing path and binding information between
HIP initiator and object(s). The datagram which is transferred to
object(s) might have the information of object ID.
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+---+ Name +-----+
DNS | |<-----------> | | Information Server
+---+ Resolution +-----+ (HIP Responder)
/ \
/ \
/ \
Find Location / \ Find objects (end points)
/ \
2)get binding information \ 1) Register object IDs
of Object ID and / \
IP address / \
/ \
/ +-------------------+
/ |+--+ |
/ || |HIP Initiator |
/ |+--+ |
/ | ++ ++ ++ |
+------+ Find path | ++ ++ ++ objects |
| |<=========================> | |
+------+ 3)connect to object(s) | ++ ++ ++ |
Client using routing path & | ++ ++ ++ |
binding information +-------------------+
Figure 6 Protocol procedure for connecting objects
7. Security Considerations
This document has specific security considerations as described in
Section 5 and aligns with the security requirements in [RFC4423] and
[RFC5201].
8. IANA Considerations
This document has no actions for IANA.
9. References
9.1. Normative References
None
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9.2. Informative References
[RFC4423] R. Moskowitz, P. Nikander, "Host Identity Protocol (HIP)
Architecture", RFC 4423, May 2006.
[RFC5201] R. Moskowitz, P. Nikander, P. Jokela, T. Henderson, "Host
Identity Protocol", RFC 5201, April 2008.
[Y.2002] ITU-T TD65 (PLEN/13), "Overview of ubiquitous networking
and of its support in NGN", consented at September 2009.
[Y.IPv6-object]ITU-T TD43 (WP5/13), "Framework of Object Mapping
using IPv6 in NGN", work in progress, September 2009.
[1] Gyu Myoung Lee, Jun Kyun Choi, Taesoo Chung, Doug Montgomery,
"Standardization for ubiquitous networking in IPv6-based NGN",
ITU-T Kaleidoscope Event - Innovations in NGN, pp.351-357, May
2008.
[2] EPCglobal, "EPCglobal Object Name Service (ONS) 1.0.1", May
2008.
[3] Content ID Forum (cIDf), "cIDf Specification 2.0", April 2007.
[4] Heer, Varjonen, "HIP Certificates," IETF Internet-Draft, draft-
ietf-hip-cert-02.txt, work in progress, October 2009.
Author's Addresses
Gyu Myoung Lee
Institut TELECOM, TELECOM SudParis
9 rue Charles Fourier, 91011, Evry, France
Phone: +33 (0)1 60 76 41 19
Email: gmlee@it-sudparis.eu
Jun Kyun Choi
Korea Advanced Institute of Science and Technology (KAIST)
119 Munjiro, Yuseong-gu, Daejeon, 305-732, KOREA
Phone: +82-42-350-6122
Email: jkchoi@ee.kaist.ac.kr
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Seng Kyoun Jo
Electronics and Telecommunications Research Institute (ETRI)
138 Gajeongno, Yuseong-gu, Daejeon, 305-700, KOREA
Phone: +82-42-860-6461
Email: skjo@etri.re.kr
Jeong Yun Kim
Electronics and Telecommunications Research Institute (ETRI)
138 Gajeongno, Yuseong-gu, Daejeon, 305-700, KOREA
Phone: +82-42-860-5311
Email: jykim@etri.re.kr
Noel Crespi
Institut TELECOM, TELECOM SudParis
9 rue Charles Fourier, 91011, Evry, France
Phone: +33 (0)1 60 76 46 23
Email: noel.crespi@it-sudparis.eu
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