ISO/IEC TR 29181-8:2017
(Main)Information technology — Future Network — Problem statement and requirements — Part 8: Quality of Service
Information technology — Future Network — Problem statement and requirements — Part 8: Quality of Service
ISO/IEC TR 29181-8:2017 describes the problem statements of current networks and the requirements for Future Network (FN) in the Quality of Service (QoS) perspective. This document mainly specifies: - problems of the current networks for QoS; - requirements for QoS support in Future Network.
Technologies de l'information — Réseaux du futur — Énoncé du problème et exigences — Partie 8: Qualité de service
General Information
Standards Content (Sample)
TECHNICAL ISO/TR
REPORT 29181-8
First edition
2017-04
Information technology — Future
Network — Problem statement and
requirements —
Part 8:
Quality of Service
Technologies de l’information — Réseaux du futur — Énoncé du
problème et exigences —
Partie 8: Qualité de service
Reference number
ISO/TR 29181-8:2017(E)
©
ISO 2017
---------------------- Page: 1 ----------------------
ISO/TR 29181-8:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO/IEC 2017 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/TR 29181-8:2017(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 General . 2
5.1 QoS in Future Network (FN) . 2
5.2 Related works on QoS . 3
5.2.1 ISO/IEC JTC1. 3
5.2.2 European Telecommunication Standards Institute (ETSI) . 3
5.2.3 Internet Engineering Task Force (IETF) . 3
5.2.4 Internet 2 . 3
5.2.5 Telecommunication Standardization Sector of International
Telecommunications Union (ITU-T) . 4
5.3 Prospect of QoS architecture in FN . 4
6 Problem statement of current networks for QoS . 4
6.1 QoS in current networks . 4
6.1.1 IPv4/IPv6 network . 4
6.1.2 Next Generation Network (NGN) . 5
6.1.3 WLAN . 6
6.1.4 Wireless metropolitan area network (WMAN) . 7
6.1.5 Mobile access networks . 7
6.2 Summary of QoS problems in current networks . 8
6.2.1 General. 8
6.2.2 Lack of flexible mechanism supporting new applications . 9
6.2.3 Lack of aggregate RSVP mechanism for business with same QoS requirements . 9
6.2.4 Lack of network self-adaptability .10
6.2.5 Lack of connection-oriented characteristics .10
6.2.6 Lack of fundamental effectiveness .10
6.2.7 Lack of standards for QoS mechanism between heterogeneous networks .10
6.2.8 Lack of consideration from user perspective .10
6.2.9 Poor controllability .10
6.2.10 Human factors .10
6.2.11 Lack of effective congestion management .10
7 Requirements of FNQoS .11
7.1 Cross-layer and global .11
7.2 Customizable user service .11
7.3 Scalability and flexibility .11
7.4 Self-adjustment.11
7.5 Focusing on mobility .11
7.6 FNQoS service composition .11
7.7 Grade and classification of services .11
7.8 Quality of Experience .12
7.9 Quality of Protection .12
7.10 Connection-mode network service .12
7.11 FNQoS control technology.12
7.12 Effective congestion control mechanisms .12
Annex A (informative) Examples of technical issues for QoS realization in FN .13
Bibliography .14
© ISO/IEC 2017 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/TR 29181-8:2017(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by ISO/IEC JTC 1, Information technology, Subcommittee SC 6,
Telecommunications and information exchange between systems.
A list of all parts in the ISO/IEC 29181 series, published under the general title Information technology —
Future network — Problem statement and requirements, is available on the ISO website.
iv © ISO/IEC 2017 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/TR 29181-8:2017(E)
Introduction
ISO/IEC/TR 29181-1 describes the definition, general concept, problems and requirements for the
Future Network (FN). The other parts of ISO/IEC 29181 provide details of various components of the
specific technology areas.
This document examines the problems of the Quality of Service (QoS) issues of current networks, and
describes the requirements in Future Network QoS architecture and functionality perspectives. It also
gives some examples of technical issues for QoS realization in Future Network (see Annex A).
© ISO/IEC 2017 – All rights reserved v
---------------------- Page: 5 ----------------------
TECHNICAL REPORT ISO/TR 29181-8:2017(E)
Information technology — Future Network — Problem
statement and requirements —
Part 8:
Quality of Service
1 Scope
This document describes the problem statements of current networks and the requirements for Future
Network (FN) in the Quality of Service (QoS) perspective. This document mainly specifies:
— problems of the current networks for QoS;
— requirements for QoS support in Future Network.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1
Future Network Quality of Service
FNQoS
overall performance of a Future Network, including two aspects: QoS (Quality of Service) and QoE
(Quality of Experience)
3.2
Future Network Proxy
FNProxy
entity, which replaces task submitter to execute particular assignments and shields them from
implementation details and processes
Note 1 to entry: FNProxy may contain sub-proxies.
© ISO/IEC 2017 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO/TR 29181-8:2017(E)
4 Abbreviated terms
3G 3rd generation
AF assured forwarding
BE best-effort service
CoS class of service
CR-LDP constrain based routing- label distribution protocol
Diff-serv differentiated service
EF expedited forwarding
GoS grade of service
HC hybrid coordinator
Int-serv integrated service
IP internet protocol
IPTV internet protocol television
IPv4 internet protocol version 4
IPv6 internet protocol version 6
LER label switching edge router
LSP label switching path
MAC media access control
MPLS multi-protocol label switching
QoE quality of experience
QoS quality of service
TE traffic engineering
VoIP voice over IP
VPN virtual private network
WCDMA wide band code division multiple access
WLAN wireless local area network
WMAN wireless metropolitan area network
5 General
5.1 QoS in Future Network (FN)
Distinguished from the traditional communication technology or information technology services, the
services of the future are various. A large number of real-time applications are emerging. Multimedia
applications such as video conference and IPTV have strict requirements to delay, jitter, bandwidth, and
2 © ISO/IEC 2017 – All rights reserved
---------------------- Page: 7 ----------------------
ISO/TR 29181-8:2017(E)
so on. High speed mobile data services need service convenience and stability. Therefore, there is an
urgent requirement to FN to provide the corresponding QoS assurance.
In addition, the meaning of the QoS concept has undergone profound changes, from network performance
parameters to those related to the user’s experience, perception of end-to-end QoS. A new approach
to QoS has been developed, strengthening the thinking that the isolated study of each QoS term can’t
bring about an effective QoS management. In the new telecommunication environment, a more complex
analysis is needed to cover the interests of all the different actors involved in the service provision. The
standardization and regulation bodies have realized that a new QoS regulatory framework is needed to
encompass the evolution of the QoS and combine with the user’s point of view.
Therefore, there is a need for a global and general QoS framework to unify criteria in terms of concepts
and terminology and to cover all the different aspects that should be considered for a practical QoS
management model in the FN environment. FN should support QoS from user and/or application
perspectives. In addition, FNQoS should also take full account of the requirements of the FN user and
applications, such as user-customization, heterogeneous networks, context-awareness, autonomy,
mobility, and service composition, etc.
5.2 Related works on QoS
5.2.1 ISO/IEC JTC1
JTC1/SC 21 (which was disbanded and its work transferred to JTC 1/SC 6) published a QoS framework:
ITU-T/Recommendation X.641(1997)∣ISO/IEC 13236:1998 to define a QoS framework under the OSI
Reference Model: QoS framework concept; QoS characteristics with respect to the user requirements;
QoS management; and QoS mechanisms. Multiple QoS entities coordinate mutually to accomplish QoS
tasks. Entities receive QOS requirements and analyse them, then determine the QOS management
mechanisms or functions that are required to meet them.
5.2.2 European Telecommunication Standards Institute (ETSI)
The TIPHON Working Group (which was disbanded) of ETSI developed the next-generation
telecommunications network architecture, which is characterized by the convergence of
telecommunications and IP. In the QoS architecture of ETSI TIPHON, TRM (Transmission Resource
Manager) is introduced in the core IP network to dynamically manage the resource scheduling of
the core network, and achieve the capability of real-time traffic engineering. TRM accepts business
resource applications of the access layer, allocates and manages the resources of core backbone and the
forwarding path for business.
5.2.3 Internet Engineering Task Force (IETF)
IETF has defined several models and mechanisms to achieve IP QoS, such as Int-serv/Diff-serv, MPLS,
QoS routing, etc. In order to satisfy user requirements and provide better QoS guarantee in the future,
the basic QoS models can be complementary each other and combined on different network layers.
For example, Int-serv and Diff-serv combination can be taken into account, which Diff-serv is used in
the core network and Int-serv is used in access network. Similarly, MPLS and Diff-serv combination or
MPLS and QoS routing combination can be considered.
5.2.4 Internet 2
A major goal of Internet 2 research was to create a scalable, interoperable and manageable QoS
architecture so that it can achieve some applications that can’t be realized in the existing Internet,
such as telemedicine, digital libraries and virtual laboratories. A test bed called QBone had been set
up for testing, developing and deploying the QoS of the next generation Internet. Diff-serv mechanisms
enhanced the QoS in Internet 2. The research result of Internet 2 showed that any viable QoS
architecture must scale well both with respect to the large numbers of flows and high forwarding rates
of core routers.
© ISO/IEC 2017 – All rights reserved 3
---------------------- Page: 8 ----------------------
ISO/TR 29181-8:2017(E)
5.2.5 Telecommunication Standardization Sector of International Telecommunications
Union (ITU-T)
ITU-T SG 12 and 13 groups are committed to studying QoS, and many recommendations have
been already developed. Recommendation ITU-T Y.2113 specified service definitions and general
requirements, a QoS control architecture, and a control coordination protocol acting as a bridge
between a single end-to-end request and the heterogeneity of the admission control mechanisms that
are already deployed in the network. Recommendation ITU-T Y.2237 introduced a functional model and
service scenarios related to the support of QoS-enabled mobile voice VoIP service in WLAN, 3G, and
WMAN networks. Recommendation ITU-T Y.1566 specified a limited set of classes that provide a basis
for interworking between the different traffic class aggregates of different service providers which
aims on enabling end-to-end QoS across different packet networks. Recommendation ITU-T Y.1545
provided the roadmap for the QoS interconnected networks that use the Internet protocol.
5.3 Prospect of QoS architecture in FN
From the point of the research works of the standards organizations, the unified QoS implementation
of the whole network still lacks the framework files for the converged heterogeneous networks in
the future, and there is also not the implementation of the specific technical specifications. This will
be the focus of international standards organizations to research and develop in the next few years.
Operators, research institutions and equipment manufacturers in the world are positive to develop the
QoS mechanisms and technologies of FN.
FN is a combination of various heterogeneous networks, and is open, high speed, high performance. To
a variety of terminals and a variety of business requirements of user under different scenarios, FNQoS
architecture need to be based on the features of user needs, the perception of network configuration,
and network real-time running status to provide services for user intelligently and dynamically. And
the architecture should eventually quantify the QoS and feed this back to the user. That architecture is
a complete system, which could achieve a unified service access control and unified strategy control.
The FNQoS architecture should contain multiple components inside. Each component has a certain QoS
function. They can provide QoS services to each other, and effectively enhance the business QoS and
quality of the user experience. In short, FNQoS architecture should meet all the future requirements of
user and try to provide satisfactory services for them.
6 Problem statement of current networks for QoS
6.1 QoS in current networks
6.1.1 IPv4/IPv6 network
The definition of QoS given by ITU-T is that QoS is the total effect of service performance, which
determines the degree of satisfaction of a user with the service. From a technical perspective, QoS is a
set of parameters required by services. Network must meet these requirements in order to ensure the
appropriate service level of data transmission. QoS technology may guarantee that applications can
share network resources effectively.
Under the network hierarchy division, each pair of the upper layer and the lower layer needs to supply
or request network resources for each other. There is an abstract relationship of services. So the
concepts of QoS exist in each layer. Due to some historical reasons, the concept regarding IP QoS is
very chaotic. Different research groups such as ITU, ETSI, ISO and IETF have different definitions for
IP QoS, and connotations of these definitions are different. The definition on IP QoS of the IETF in
the field IP technology research has been most widely recognized. But IETF did not give the uniform
definition of IP QoS.
There are several models or mechanisms for the IP QoS:
(1) Int-serv
4 © ISO/IEC 2017 – All rights reserved
---------------------- Page: 9 ----------------------
ISO/TR 29181-8:2017(E)
Int-serv mainly introduces an important network control protocol RSVP (Resource Reservation
Protocol). RSVP makes IP applications provide the required end-to-end QoS. Although Int-serv provides
guaranteed QoS, it has poor extensibility. Because Int-serv works based on each flow, it will need
to maintain a lot of state information proportional to the number of packet queues. In addition, the
effective implementation of the RSVP must depend on each router on the path. In the backbone of the
Internet, the number of packet flows is quite large, so the router’s forwarding rate is very high. This
makes the Int-serv difficult to implement in the backbone network.
(2) Diff-serv
Diff-serv aims to define a way of implementing QoS that is easier to extend to overcome the problems of
Int-serv. Diff-serv simplifies signalling, and makes more coarse granularity classification to IP packet
flow. Diff-serv provides QoS by way of aggregating and PHB (per-hop behaviour). Aggregating refers
to the fact that IP packet flows with similar QoS requirements are seen as a class. This can reduce the
number of queue handled by scheduling algorithms. The IP packet is forwarded in the way of PHB. Each
PHB defines the packet-forwarding properties associated with a class of traffic. Diff-serv does not need
to reserve the information of flow status and signalling, and has better scalability. But there is lack of
end-to-end bandwidth reservation. The service guarantee may be weakened in the congested link.
(3) Int-serv/Diff-serv combination
The basic idea of the Int-serv/Diff-serv combination model is that the Int-serv model and Diff-serv
model are combined in the whole network. An end-to-end QoS guarantee is provided for applications
and services according to the adoption of the Int-serv model in the edge network. The core network
is still using the Diff-serv model. But the new model still has very obvious flaws, such as complex
signalling, a complex operation management level, and so on. For the current point of view, although
the Int-serv/Diff-serv combination model has theoretical feasibility, there is still a long period of
exploration.
(4) MPLS (Multi-Protocol Label Switching)
MPLS combines IP routing and layer 2 label-switching, which adds a label between the head of data
frame in layer 2 and the head of packet in layer 3. Network routers transmit and process data through
the identification of labels. MPLS is obviously different to the traditional router in routing addressing,
and packets can be forwarded along different paths to the same destination. MPLS makes up for the
many defects of a traditional IP network and introduces an “explicit routing” mechanism to provide a
more reliable guarantee of QoS. But the signalling of the connection established is very complicated and
the flexibility of routing is not high. There is low efficiency when shorter data are transmitted.
(5) TE technology based on MPLS
When the traffic is mapped onto the physical topology of the network as well as the task of locating
these resources for the traffic, this is known as Traffic Engineering (TE). It is also the important method
to achieve network congestion control and implementation of QoS. MPLS is suitable to combine with
TE. MPLS TE is an indirect technology to improve network performance. MPLS TE uses the ability that
LSP support display routing to: guide the network traffic reasonably; make the real network traffic
load match the physical network resources; and improve the network QoS indirectly. According to
user requirements (display routing, bandwidth, etc.) and the situation of the network resources, MPLS
TE automatically establishes a cross backbone and connects two LER tunnels through the CR-LDP
signalling (or an RSVP extension), at the same time it completes the maintenance, statistics, property
modification (such as bandwidth) and back-up of the tunnel. The MPLS TE tunnel can be widely used in
VPN, all kinds of access and Internet traffic. However, the technical proposal has its own problems. The
tunnel connecting two label edge routers is usually not able to perceive the type of traffic. If EF, AF and
BE at the same time emerge in the tunnel, traffic will interfere with each other.
6.1.2 Next Generation Network (NGN)
ITU-T SG13 research team has developed a proposal draft on QoS reference architecture in NGN. The
draft considered that the cooperation of a service control layer, bearer control layer and network bearer
layer can provide the QoS guarantee in NGN.
© ISO/IEC 2017 – All rights reserved 5
---------------------- Page: 10 ----------------------
ISO/TR 29181-8:2017(E)
The service controller is the core of the service control layer, which handles the requirements of users
in the network and determines the QoS needs of each service stream. The service controller sends the
resource requests from each specific service stream to the bearer control layer. The bearer control
layer is responsible for implementation. Therefore, the QoS needs of the service stream can be met. The
service controller may be soft switch, application server, load gateway and so on. In the network, these
three components are complementary and indispensable, and form the basis of the QoS guarantee.
At this stage, there are two ideas to provide a QoS guarantee for NGN. One solution is to start from the
network structure and transport model, such as Int-serv, Diff-Serv and MPLS. Another idea is to combine
the network call control and the state analysis of QoS. For ITU-T NGN QoS, there were three levels to
manage network QoS. Its main problem is that technologies of the network-bearing layer are limited
to the IP backbone network, but Future Network may contain a variety of networks. A referenced QoS
[17]
architecture of the NGN is shown in Figure 1 .
Figure 1 — ITU-T reference architecture of QoS o
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.