INTAREA Working Group S. Bryant
Internet-Draft U. Chunduri
Intended status: Informational T. Eckert
Expires: January 14, 2021 A. Clemm
Futurewei Technologies Inc.
July 13, 2020
Forwarding Layer Use Cases
draft-bryant-arch-fwd-layer-uc-00
Abstract
This document considers the new and emerging use cases for IP. These
use cases are difficult to address with IP in its current format and
demonstrate the need to evolve the protocol.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Forwarding Layer . . . . . . . . . . . . . . . . . . . . 3
2. New Use Cases for packet networks . . . . . . . . . . . . . . 3
2.1. Role of Fixed Networks in 5G and Beyond 5G . . . . . . . 4
2.2. Convergence of Industrial Control Networks . . . . . . . 4
2.3. Cloud Based Industrial Automation . . . . . . . . . . . . 5
2.4. Volumetric Data Transmission . . . . . . . . . . . . . . 6
2.5. ITU-T Focus Group Network-2030 . . . . . . . . . . . . . 6
2.6. Emerging and New Media Applications . . . . . . . . . . . 7
3. Deployment Models . . . . . . . . . . . . . . . . . . . . . . 8
3.1. Traditional Deployment Models . . . . . . . . . . . . . . 8
3.1.1. Best-effort Internet . . . . . . . . . . . . . . . . 8
3.1.2. Enhanced Service . . . . . . . . . . . . . . . . . . 9
3.1.3. Over-the-top (OTT) Providers . . . . . . . . . . . . 10
3.1.4. Cooperating Providers . . . . . . . . . . . . . . . . 10
3.2. Emerging Deployment Models . . . . . . . . . . . . . . . 11
3.2.1. Embedded Service . . . . . . . . . . . . . . . . . . 11
3.2.2. Embedded Global Service . . . . . . . . . . . . . . . 12
3.2.3. Changing Fixed Access Models (1 or 2 Providers) . . . 13
3.2.4. Single "Underlay" provider E2E for 5G/B5G network
(Cellular/Access Networks) . . . . . . . . . . . . . 13
3.3. Envisioned New Deployment Models . . . . . . . . . . . . 14
3.3.1. Network Slicing . . . . . . . . . . . . . . . . . . . 14
3.3.2. Private 5G Networks . . . . . . . . . . . . . . . . . 15
3.4. Limited Domains . . . . . . . . . . . . . . . . . . . . . 15
4. New Network Services and Capabilities . . . . . . . . . . . 16
4.1. New Services . . . . . . . . . . . . . . . . . . . . . . 16
4.2. New Capabilities . . . . . . . . . . . . . . . . . . . . 17
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
6. Security Considerations . . . . . . . . . . . . . . . . . . . 18
7. Appendix 1: Expanded Summary of Sub-G1 Use Cases . . . . . . 18
7.1. Holographic-type communications . . . . . . . . . . . . . 18
7.2. Tactile Internet for Remote Operations . . . . . . . . . 19
7.3. Space-Terrestrial Integrated Networks . . . . . . . . . . 20
7.4. ManyNets . . . . . . . . . . . . . . . . . . . . . . . . 20
8. Appendix 2: Expanded Summary of Sub-G2 New Network
Capabilities and Services . . . . . . . . . . . . . . . . . . 21
8.1. New Services . . . . . . . . . . . . . . . . . . . . . . 21
8.1.1. High-Precision Communications Services . . . . . . . 22
8.1.2. In-time Services . . . . . . . . . . . . . . . . . . 22
8.1.3. On-time Services . . . . . . . . . . . . . . . . . . 22
8.1.4. Coordinated Services . . . . . . . . . . . . . . . . 23
8.1.5. Qualitative Communication Services . . . . . . . . . 23
8.2. New Capabilities . . . . . . . . . . . . . . . . . . . . 23
8.2.1. Manage ability . . . . . . . . . . . . . . . . . . . 24
8.2.2. High Programmability and Agile Life-cycle . . . . . . 24
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8.2.3. Security . . . . . . . . . . . . . . . . . . . . . . 25
8.2.4. Trustworthiness . . . . . . . . . . . . . . . . . . . 27
8.2.5. Resilience . . . . . . . . . . . . . . . . . . . . . 27
8.2.6. Privacy-Sensitive . . . . . . . . . . . . . . . . . . 27
8.2.7. Accountability and Verifiability . . . . . . . . . . 28
9. Informative References . . . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31
1. Introduction
There is an emerging set of new requirements that exceed the network
and transport services of the current Internet, which currently only
delivers "best effort" service. While many controlled or private
networks include further services, such as other DiffServ QoS in
addition to best effort and traffic engineering with bandwidth
guarantees, the solutions used today only support walled gardens and
are thus they are not available to application service providers and
consumers across the Internet.
The purpose of this document is to look at current, evolving and
future use cases that need to addressed by the Internet forwarding
layer. In parallel with this use case study, a study of the gaps
between the capability of the existing IP forwarding layer and the
requirements described in this use case study is provided in
[I-D.bryant-arch-fwd-layer-ps]. It is thus the purpose of this text
to provide the wider context for the forwarding layer problem
statement.
The purpose of this text is thus to stimulate discussion on the
emerging contexts in which the forwarding layer will need to operate
in the future.
1.1. Forwarding Layer
The term "forwarding layer" is used in this document to indicate that
that development work will likely need to reach down to layer 2.5 in
order to ensure that packets are handled correctly down to the
physical layer, and that it is equally it is possible that
development work will need to reach into the transport layer. This
is described in more detail in [I-D.bryant-arch-fwd-layer-ps].
2. New Use Cases for packet networks
This section summarizes the use case areas that have been observed by
the authors, and are considered relevant to any analysis of the gaps
in forwarding layer capabilities.
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This section is structured into sub-sections discussing either group
of use cases directly or the work of specific groups that are
identifying use cases and that may also work on identifying issues
and or proposed architectures or solutions for them.
Subsections are ordered from what might be considered to be the most
near-term use cases to the potentially most far reaching ones.
2.1. Role of Fixed Networks in 5G and Beyond 5G
The 5G and beyond 5G (B5G) services are not meant to be limited to
the 5G-NR (new-radio). In fact for those services relating to uRLLC,
and mMTC packet networks have evolve along with the radio
technologies. While 5G-NR protocol stack has evolved to provide per-
frame reliability and latency guarantees, the IP/MPLS transport
network by-and-large remains best-effort. It is no longer possible
to solve network problems simply by increasing the capacity
[SysArch5G]. The expectations 5G devices have of 5G networks, can
not be met without improving IP/MPLS based back-haul networks. For
example, the 5G based systems involve machine to machine
communications, generally using command-based smaller payloads. In
this case the overheads of packet headers and overlays become
apparent when computing latency budget of such packets.
The IETF has produced a large body of work on the deterministic needs
of network applications [RFC8578]. These range from refinements and
expansions of above summarized Audio/Video and AR/VR use cases over
gaming into many more "industrial" use cases. Industrial use cases
generally involve industrial controllers for high-precision machinery
and equipment, such as robotic arms, centrifuges, or manufacturing
equipment for the assembly of electronic components.
These use cases have in common that they require delivery of packets
with very precise and "deterministic" performance characteristics, as
the controlled equipment and the control loops involved have very
exact timing requirements and are not tolerant of any latency
variations, as otherwise control loop issues and other undesired
effects may occur.
Specifically, the use cases involve curtailing maximum latency that
could be incurred. However, deterministic networking, by itself,
does not appear to be sufficient to meet all of the emerging needs.
2.2. Convergence of Industrial Control Networks
Industrial control networks exist to serve specialist applications
and are deployed in well controlled networks subject to tight timing
and reliability constrains and tight security constraints. They
mostly use bespoke, application specific proprietary protocols.
There is a desire to achieve economy of scale by using a single
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protocol, and to integrate the production network with the back-
office network. The obvious protocol to use would be IP, but to be
deployed in this mixed application environment IP needs to satisfy
the non-negotiable needs of the industrial control network such as
timing, reliability and security.
2.3. Cloud Based Industrial Automation
Future industrial networks are significantly different from best
effort networks in terms of performance and reliability requirements.
This is discussed in [NET2030SubG1]. These networks need more than
basic connectivity between the back office and the factory floors,
instead they require integration from devices all the way through to
the business systems. This permits many new types of UI and full
automatic operation and control of industrial processes without
significant human intervention. These networks need to deliver
better than best effort performance, and require real-time, secure,
and reliable factory-wide connectivity, as well as inter-factory
connectivity at large scale.
Such systems typically require low end-to-end latency to meet closed
loop control requirements. Such system also need low jitter
connectivity. IIoT systems, as an example contain many control sub-
systems that run at cycle times ranging from sub-ms to 10 ms. In
such systems, end-to-end control requires in-time signaling delay at
the same cycle time level, without malfunctions. These low latency
requirements of IIoT applications are increasingly not only relevant
to internal system communications, but also becoming essential for
the interconnection of remote systems.
As another example, it is a fundamental requirement for multiple-axis
applications to have time synchronization in order to permit
cooperation between various devices, sometimes remotely. In order to
recover the clock signal and reach precise time synchronization, the
machine control, especially the motion control sub-system, requires
very small jitter at sub- microsecond level, and such small jitter is
expected to have bounded limits under some critical situations.
In some IIOT systems a service availability of 99.999999% is needed,
as any break in communications may be reflected as a million-dollar
loss. At the same time, as part of the Industry 4.0 evolution,
operational technologies (OT) and information technology (IT) are
converging. In this model control functions traditionally carried
out by customized hardware platforms, such as Programmable Logic
Controllers (PLC), have been slowly virtualized and moved onto the
edge or into the cloud in order to reduce the CAPEX and OPEX, and to
provide increased system flexibility and capability and to allow 'big
data' approaches. This move of industrial system to the cloud places
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higher requirements on the underlying networks, as the latency,
jitter, security and reliability requirements previously needed
locally have to be implemented at larger scales.
2.4. Volumetric Data Transmission
Volumetric Data refers to cases where very large data sets need to be
transferred continuously in real time. One example is Immersive AR/
VR media transmission Section 2.6. Another example is V2X with many
sensors continuously generating data which needs to made available
for, amongst other reasons, technical analysis by the manufacturer as
part of product development, and insurance purposes.
2.5. ITU-T Focus Group Network-2030
The ITU-T has been running a Focus Group (FG) Network-2030
[FGNETWORK2030] to analyze the needs of networks in the period post
2030. This work started in July 2018 and submitted it report to
ITU-T Study Group 13 in June 2020. It has been an open process with
contribution by a cross-section of the networking industry. Because
this is non-IETF work, this section summarizes the currently
finalized key findings of the ITU-T Focus Group Network-2030 to make
it easier for the reader to better understand the work. Note that
this work is still ongoing and additional findings may be published.
The Focus Group Network 2030 considered a number of use cases that it
was postulated would need to be addressed in the 2030 time-frame and
the technology gaps that need to be bridged in order to address these
needs. It then considered a number of new network services that
would be needed to support these services.
An ongoing piece of work on the architecture of the network post 2030
has not yet been completed at the time of writing and is only
partially discussed in this document.
The reader is referred to [WP], [NET2030SubG2], [UC] for information
beyond that provided in this summary.
ITU-T FG NET2030 Sub-group Sub-G1 (Sub-G1) considered a number of use
cases that it considered to be representative of the network needs
post 2030. These needs are legitimate needs in their own right, but
as is always the case act as poster-children for new applications
that will inevitable conceived in the light of the new network
capabilities that we postulate to be necessary.
o Holographic-type communications (HCT)
o Tactile Internet for Remote Operations (TIRO)
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o Network and Computing Convergence (NCC)
o Digital Twin (DT)
o Space-Terrestrial Integrated Networks (STIN)
o ManyNets
o Industrial IoT (IIoT) with cloudification.
Further information on these use cases is provided in Section 7, and
in the ITU documents [UC] and [WP].
Note to the reader: Unlike ITU-T Study Groups which are restricted to
members, ITU-T Focus Groups are open to anyone without payment. At
the time of writing, ITU-T Focus Group Network-2030 material that is
not available for anonymous download, is accessible for free by
joining the Study Group.
2.6. Emerging and New Media Applications
Audio/Video streaming for production, entertainment, remote
observation, and interactive audio/video are the most ubiquitous
applications on the Internet and private IP networks after web-
services. They have grown primarily through an evolution of the
applications to work with the constraints of todays Internet and
adopting pre-existing infrastructure such as content caches: best-
effort streaming with adaptive video, no service guarantees for most
services, and co-location of caches with large user communities. In
environments where more than best-effort services for these
applications are required and deployment of current technologies to
support them is feasible, it is done. Examples include DiffServ or
even on or off-path bandwidth reservations in controlled networks.
Networked AR/VR is a very near term set of use cases, where solution
models are very much attempting to use and expand existing solution
approaches for video network streaming but where the limits of above
current best practices are also amplified by the larger bandwidth
requirements and stricter latency and jitter requirements of AR/VR.
To ensure a good user experience, for live Virtual Reality (VR), a
much higher resolution than 8K video is required. In addition to the
high bandwidth requirements of VR, there needs to be a supporting
transmission network to provide a communications path with bounded
low latency as well. This stringent VR latency requirement is a
challenge to existing networks.
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In cellular networks, even though the the air interface link latency
needed is significantly reduced e.g. with New Radio (5GNR), the end-
to-end (E2E) requirements for live VR is harder to meet. This is
because of the fixed L2/IP/MPLS networks in front/mid/backhaul
components, and because of the best effort nature of the packet
delivery systems in these networks.
3. Deployment Models
In this section we look at a number of network deployment models. We
group these deployment models into three types:
o The traditional deployment models
o Emerging deployment model models
o Envisioned new deployment models
The service requirements demanded from the networks and security
implications vastly differ in these different deployment models.
A few general observations are useful in providing context to this
section:
o End to End traffic over the Internet backbone is becoming minority
traffic.
o Commercial deployments do not operate the way they used to when
many of the original Internet protocols and invariants were
established.
o The application trajectory is for the applications to be hosted on
(protected) servers a few hops from the user.
o Applications are becoming self-contained and use their own stack
which is tunneled over UDP/IP to the server.
3.1. Traditional Deployment Models
In this section we look at the traditional deployment models that
have been in existence for many year and formed the foundation of
Internet.
3.1.1. Best-effort Internet
In this model connectivity is edge-to-edge, and in the general case
the edge connectivity is provided by a service provider who peers
with a transit provider that provides connectivity to other service
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providers possibly via other transit providers. This is shown in
Figure 1.
+---+ +---+
| H | |Svr|
+-+-+ +-+-+
| SP1 Internet SP2 |
| .......... ..................... ......... |
+-+--+ .+----+ . .+---+ +---+ +---+' . +----+. +-+-+
| CE +--+ PE +------+AS1+--+AS2+--+AS3+------+ PE +---+ CE|
+----+ .+----+ . .+---+ +---+ +---+. . +----+. +---+
.......... ..................... .........
Figure 1: An Edge-2-Edge Classical Internet
This service is generally known as "best-effort" in that each element
of the service path undertakes to do no more that try its best to
provide equitable service to all traffic. These are traditional E2E
deployments where communication endpoints of the data traffic on
different provider networks with regional, transit network providers
through Internet Exchange Providers (IXPs) providing the global inter
connection. The term lower-common-denominator might be a better term
in that the service quality is the service of the worst element of
the path on a packet by packet basis.
This model is in the process of being replaced by a model in which
the most popular and important service are provided at the edge with
Internet transit traffic being used where there is no alternative.
In this case the provider controls only the path to the CE and can
certify the correct operation of the service according to contract
from that point but the user is responsible for providing the
required service characteristics into their own network.
In this network environment it is difficult to support any form of
enhanced service since it is unlikely that the whole path is know to
support extended capabilities in the forwarding plane. It is not
infeasible, and it would be possible to set up such paths in
principle given suitable enhancements to the routing system. However
such a scenario must be considered infeasible for the foreseeable
future.
3.1.2. Enhanced Service
This is the traditional service provider deployment where various
network services (VPN, security, Bandwidth..) are offered to the
endpoints of the communication and other providers. Such
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capabilities are purchased through contract with the service provider
and are typically expensive.
These networks predominantly use MPLS technology though native IP
(IPv4/IPv6) with GRE and IPv6 with routing extension headers with
SRv6 are being deployed recently.
..................................
+---+ . +---+ Single +---+ . +---+
|CE1|---|PE1|---.. Provider ..---|PE2|---|CE2|
+---+ . +---+ Network +---+ . +---+
..................................
Figure 2: An Edge-2-Edge Network
In this case there is a single provider network in which E2E
offerings and host session are initiated and terminated with in the
single provider network.
3.1.3. Over-the-top (OTT) Providers
In this model the endpoints of the communication (virtual or physical
hosts) consuming services through with in the OTT provider network
servers (Cloud and Data Center (DC) networks); where the other
endpoint can be in the same server form or on the DC Gateway or on
the other end of the DC Server Farm connected through Data Center
Interconnect (DCI).
The local provider is thus just a connectivity provider to opaque
traffic with no ability to enhance the service. However the
corollary to this is that whilst the the OTT provider has full
control of what happens whilst the user data is within their network
they have no control over how the user traffic transits to them
across the "public" network.
3.1.4. Cooperating Providers
Where two providers interconnect with no Internet Transit Network:
Another variant of the E2E connectivity can be seen as evolving
comprises only endpoints provider (access) network and receiver
access provider network with global transit provided by one ISP.
This case is more tractable provided there is co-operation between
the providers.
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3.2. Emerging Deployment Models
The emerging model is to provide the service close to the user by
embedding that service with the service provider network. This has
three advantages, firstly that the service latency is lower, secondly
that that there is less transit traffic that the network provider
needs to manage or pay for, and thirdly that the service availability
and reliability is in the hands of the network provider that the
customer is contracted to.
3.2.1. Embedded Service
The industry move is towards content and application service
providers embedding themselves within the edge network. This is
currently done to save bandwidth and improve response time. As the
need for high precision low latency networking develops the need for
edge computing rises since the closer the client and the server the
less the scope for network induced performance degradation.
+---+
| H |
+-+-+
|
| .....................................
+-+--+ .+----+ +---+ .
| CE +--+ PE |--------+Svr| .
+----+ .+----+ +---+ Provider 1 .
.....................................
Figure 3: An Edge-2-Provider
In this network the server S (owned by the content and applications
provider) has a contractual relationship with provider 1 and is thus
able to negotiate the network characteristics needed to meet its
service requirement. This model in which the server brokers the user
to network interface (UNI) requirements removes many of the
objections to the classical UNI model in which the client requests
the service requirements. In this model the host authenticates
itself with the server, having formed a previous business
relationship (for example by purchasing a holographic conferencing
service). The server has a relationship with Provider1, and thus is
a trusted party able to request that the service be set up between
itself and and its client, paying as necessary. As this is a
requested paid service traversing a limited distance over a defined
network, a bespoke packet protocol can, if necessary, be used with in
a contained and constrained way.
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How the server communicates with any other part of the application
domain is out of scope for this document and possibly out of scope
for Provider 1.
This takes us to consider the embedded global service described in
{#EGS}.
3.2.2. Embedded Global Service
+---+
| H1|
+-+-+
|
| ......................................
+-+--+ . +----+ +---+ .
| CE +---+ PE |--------+ S1| .
+----+ . +----+ +-+-+ Provider 1 .
..................|...................
|
|Private Peering
|
..................|...................
+----+ . +----+ +-+-+ .
| CE +---+ PE |--------+ S2| .
+----+ . +----+ +---+ Provider 2 .
| ......................................
|
+-+-+
| H |
+-+-+
Figure 4: Edge-2-Edge via Provider
In this network model, the server S1 (owned by the content and
applications provider) has a contractual relationship with provider 1
and is thus able to negotiate the network characteristics needed to
meet its service requirement. It is servicing the needs of host H1.
Similarly that same provider has a contractual relationship with
provider 2 where it is servicing the needs of host H2.
By a method outside the scope of this document and outside the scope
of the global Internet the contents and applications provider has a
private path between S1 and S2.
This scenario shown in Figure 4 is important because it removes the
overwhelming issues associated with providing enhanced service across
the global Internet. Furthermore it describes a model where there is
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commercial incentive, at scale, for the edge providers (Provider 1
and 2 above) to invest in providing and enhanced access service.
3.2.3. Changing Fixed Access Models (1 or 2 Providers)
The preceding sections are the basis for a change in the network
fixed access model.
The access network either connects to a data center gateway or one is
embedded in the access network. This gateway either passes the
traffic to a locally connected data center that provides the required
service or passes it over a private global data center interconnect
to a partner data center for service provision. Such a connection
provides service model in which the required service level cane be
more readily addressed.
H H
| |
| |
Access NW
\
\
DC-GW==Private Global==DC-GW
// DCI \\
DC Fabric DC Fabric
| | | | | | | | | |
S S S S S S S S S S
Figure 5: Changing Fixed Access Model
3.2.4. Single "Underlay" provider E2E for 5G/B5G network (Cellular/
Access Networks)
The preceding sections are the basis for the emerging change in the
structure of the 5B and Beyond 5G (B5G) network design.
Endpoints (UE's) connecting to the provider wireless or wired
networks, where service is terminated inside the provider network end
points. Based on the service offerings connection termination can
happen close to the Radio/access nodes with multi-access edge
computing (MEC) clouds or in the provider core network (core-cloud)
before going to the Internet eventually. Example of these
deployments include BNG, 4G and 5G wireless access/RAN/backhaul
networks.
Thus in Figure 6 user equipment connects to the customer site
provider edge via the radio network. This in turn is connected to
the aggregation PE which in turn determines if the traffic should be
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routed to a local data center for processing, or passed to a core
data center. At the core DC the traffic may be processed locally,
passed out to the Internet, passed to a peer DC via a private DCI, or
processed locally with the help of resources access via that external
interconnects.
User Equipment(UE)
Phone/eMBB
/ Compute Compute
\ Vehicle Storage Storage
/ / | | / Internet
\ \ Drone/UAV | | /
/ / / DC Fabric DC Fabric{
\ \ \ IIOT | | \
/ / / / | | \ Private Global
\ \ \ \ | | DCI
Radio --------CS PE----Aggr PE-----Core PE
Figure 6: 4G and 5G underlay provider network
3.3. Envisioned New Deployment Models
The emerging network deployment models are a potential vector for
fundamental change in the way the network operates.
3.3.1. Network Slicing
Network slicing is a method of creating a private subset of a public
network. Unlike VPNs it is not a simple over the top approach,
instead it is more integrated with the base network in terms of the
way the base network provides services and allocates resources. A
network slice provides significant isolation between one slice and
another and between the slice and best effort users of the network.
In an ideal slice, the users of one slice have no way of knowing
anything about the traffic in any other slice. Such a service could
be offered through statistical multiplexing techniques with real
bandwidth permanently allocated to each slice, but this would not
easily offer the statistical multiplexing that make packet networking
so economic and so flexible. In particular it would not be easy to
transparently "borrow" unused committed bandwidth in a way that was
undetectable. It seems likely that to create a high fidelity slice
will require new properties in the packet layer, either through
extension of the existing packet protocols, or through the
introduction of an alternative design. A useful discussion of
network slicing relevant to this context can be found in
[I-D.ietf-teas-enhanced-vpn].
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Largely popularized as part of 5G the concept of network slicing has
wider applicability.
3.3.2. Private 5G Networks
A use case is emerging for 5G technology in private networks. The
interest is in the protection and security that comes with the use of
licensed spectrum. Unlicensed spectrum offers no protection against
other users of that spectrum and thus another aspect of best effort
comes into play, not only is the network best effort with respect to
traffic within the network (an addressable problem) but the radio is
best effort with respect to radio traffic from adjacent networks.
Without extensive radio shielding of the facility a user cannot know
if the spectrum is available for their use at any time, and they have
to suffer interference from adjacent users, who may be benignly using
the spectrum for legitimate purposes, as is their equal right, or may
be using it to cause service disruption to a commercial enterprise.
5G runs on licensed and hence protected spectrum. In return for the
paying the license fee the spectrum owner has a statutory protection
against interference.
Thus it is interesting to note that a major UK car plant just
announced the use of 5G to provide connectivity for equipment at
their manufacturing facility.
Such applications of 5G are not as architecturally constrained as
public 5G deployments and thus have the ability to make different
fundamental choices regarding their packet protocols.
3.4. Limited Domains
[I-D.carpenter-limited-domains] provides a useful insight into the
emergence of limited domains in which fewer (or different)
constraints on protocol design and operation apply. Limited domains
offer an opportunity to deploy specialist forwarding layer protocols,
designed to meet specific objectives, which are not readily addressed
by general purpose protocols such as IPv4|6 without the need to worry
about inter-working and inter-operation across the big I Internet.
Such domains can be considered sandboxes in which new proposals can
be deployed without the wider concerns of full-scale Internet
deployment.
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4. New Network Services and Capabilities
In order to support the use cases presented in Section 2, a number of
new network services will be needed. Likewise, a number of
additional more general network capabilities will becoming
increasingly important. Neither services nor capabilities are
sufficiently supported to the degree that will be required by
Internet technology in use today.
This section describes these services and capabilities at a high
level. It builds on a corresponding analysis that was conducted at
ITU-T FG-NET2030; readers are referred Section 8 for further detail
and, of course, to output produced by that group [NET2030SubG2] for a
more complete explanation of their considerations.
4.1. New Services
[NET2030SubG2] identifies a number of network services that will be
needed to support many of the new use cases. These network services
are divided into two categories:
o Foundational Services (FS) require which dedicated support on some
or all network system nodes which are delivering the service
between two or more application system nodes.
o Compound Services (CS) are composed of one or more foundational
services, and are used to make network services easier to consume
by certain applications or categories of use cases. An example of
a CS would be a Tactile Internet Service which consisted of
tactile control channel and a haptic feedback channel.
The following are a set of Foundational Services :
o High-Precision Communications Services: services with precisely
defined service level objectives related to end-to-end latency.
Three high-precision communications services that have so far been
proposed:
* In-time Services: services that require end-to-end latency
within a quantifiable limit. This service is similar to the
service provided by DetNet [RFC8655] but with more demanding
applications which need to be satisfied over IP.
* On-time Services: services require end-to-end-latency to be of
an exact duration.
* Coordinated Services: Coordinated services require multiple
interdependent flows to be delivered with the same end-to-end
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latency, regardless of any (potential additional) service level
objective.
o Qualitative Communication Services: services that are able to
suppress retransmission of less relevant portions of the payload
in order to meet requirements on latency by applications that are
tolerant to this.
These are described in more detain in Section 8.1.
4.2. New Capabilities
[NET2030SubG2] identifies also a number of network capabilities that
will become increasingly important going forward, in addition to the
support for any particular services.
A number of those need to be taken into consideration from the very
beginning when thinking about how future data-planes need to evolve.
These capabilities are described in more detail in Section 8.2.
o Manageability: Many of the services that need to be supported in
the future will require advances in measurements and telemetry
will be required in order to monitor and validate that promised
service levels are indeed being delivered. These will requires
advanced instrumentation that is ideally built.
o High Programmability and Agile Life-cycle: Methods to provide
operators need to be able to rapidly nd easily introduce new
network services and adapt to new contexts and application needs.
o Security and Trustworthiness: New mechanisms are needed to
authorize packets to enter the network from a host or from another
network, and for them to then receive the required premium service
that can operate. This must operate without impacting the latency
and MTU requirements. This security mechanism has to protect both
the network, the user data and the user privacy, but still expose
sufficient information to the network that the correct premium
service can be delivered.
o Resilience: Ultra-low-latency requirements and the huge increase
of bandwidth demands of new services such as holographic type
communication services make retransmission as a mechanism to
recover data that was lost in transit increasingly less feasible.
Therefore, network resilience and avoidance of loss becomes more
importance that it is for best effort networks.
o Privacy-Sensitive: There is a growing awareness of the lack of
privacy in the Internet and its implications.
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New network services have to be sensitive to and comply with
heightened user privacy expectations.
At the same time, the need for privacy needs to be balanced with
legitimate needs of network providers to operate and maintain
their networks, which requires some visibility into what is
happening on the network and how it is being used. There are a
variety of privacy-related requirements that ensue, such as:
* Anonymization
* Opaque User data
* Secured Storage
* Flow anonymization
o Accountability and Verifiability: Provision of the methods to
account for an verify delivery of premium services.
5. IANA Considerations
This document does not request any allocations from IANA.
6. Security Considerations
Security is likely to be more significant with the applications being
considered in this work. With interest in tightly controlled access
and latency, and contractual terms of business it is going to be
necessary to have provable right of access to network resources.
However heavyweight security is a contra-requirement to the light-
weight process needed for power efficiency, fast forwarding and low
latency. Addressing this will require new insights into network
security.
Further information on the issue of providing security in latency
sensitive environments can be found in [I-D.ietf-detnet-security]
which are a sub-set of the considerations applicable to the new use
cases considered in this text.
7. Appendix 1: Expanded Summary of Sub-G1 Use Cases
7.1. Holographic-type communications
This work projects that we will move towards a holographic society
where users remotely interact with the physical world over the
network. In industry the digital twin model will enable the control
of real objects through digital replicas. Tele-presence will move to
a new level with multi-site collaborations becoming much closer to
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physical meetings that can take place without the time and
environmental cost of physical travel. 3D medical scans will become
full 3D views rather than the body/ organ slices that too many of us
are regrettably familiar with. It is easy to imagine that this
technology will take message delivery to a completely new level.
Analysis of these concepts results in the conclusion that the
following key network requirements are necessary:
o Ultra-high bandwidth (BPS class)
o Ultra-low latency (sub-ms)
o Multi-stream synchronization
o Enhanced network security
o Enhanced network reliability
o Edge computation
7.2. Tactile Internet for Remote Operations
Two cases were proposed as examples of this class of application.
The first is remote industrial management which involves the real-
time monitoring and control of industrial infrastructure operations.
The second involves remote robotic surgery. Remote robotic surgery
within an operating suite complex is a standard practice today,
however there are cases where it would be desirable to extend the
range of this facility.
Analysis of these concepts results in the conclusion that the
following key network requirements are necessary:
o Ultra-high bandwidth (Tbps class)
o Ultra-low latency (sub-ms)
o Sensory input synchronization
o Enhanced network security
o Enhanced network reliability
o Differentiated prioritization levels
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7.3. Space-Terrestrial Integrated Networks
The game-changer in the area of space-terrestrial networking is the
active deployment of huge clusters of cheap Low Earth Orbit (LEO)
satellite constellations. These LEOs have a number of properties
that make them attractive, but arguably the most important is that
they combine global coverage with low latency. Studies [Handley]
show that for distances over 3000Km latency via a LEO cluster is
lower than the latency of terrestrial networks. The up-link to a LEO
cluster has to constantly change the point of attachment to the
cluster as the satellites that form the cluster rapidly move across
the sky relative to both the ground and relative to the satellites in
other orbits. In this scenario a number of access and connection
models need to be considered.
Analysis of these concepts results in the conclusion that the
following key network requirements are necessary:
o A suitable addressing and routing mechanism to deal with a network
that is constantly in flux.
o Sufficient bandwidth capacity on the satellite side to support the
new application needs
o A suitable satellite admission system
o Edge computation and storage
7.4. ManyNets
There is evidence that there is a change in direction from the
Internet as a single hetrogenious network back to a true Internet,
that is an interconnection of a number of networks each optimized for
its local use but capable of inter-working.
For example, satellite and the terrestrial networks adopt different
protocol architecture, which causes the difficulty to internetwork
between them, yet the common goal is to provide access to the
Internet. Secondly, there will be a massive number of IoT-type
devices connecting to the networks but the current interconnection
schemes are too complex for these services. There are further trends
in 5G/B5G back-haul infrastructure, requiring diverse set of resource
guarantees in networks to support different industry verticals. The
collection of such special purpose networks, existing together and
requiring interconnection among themselves are called ManyNets.
Much closer the traditional Internet model is the move to edge
computing services in which the client traffic is terminated at a
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compute node very close to access edge. [DOT] Any resultant
application traffic is a private matter between the application on
the edge server and the servers it communicates with in the
fulfillment of those needs. Furthermore the application on the
client may be using a tunnel to the edge compute server. In such a
network the protocol used inside the tunnel and the protocol used
between the servers executing the service is a private matter.
The ManyNets concept aims to support flexible methods to support the
communication among such heterogeneous devices and their networks.
8. Appendix 2: Expanded Summary of Sub-G2 New Network Capabilities and
Services
This appendix expands on the ITU-T Sub-G2 new network capabilities
and services introduced in Section 4 It builds upon the analysis that
was conducted at ITU-T FG-NET2030; readers are also referred to
output produced by that group [NET2030SubG2] for more detail.
8.1. New Services
[NET2030SubG2] identifies a number of network services that will be
needed to support many of the new use cases. These network services
are divided into two categories:
o Foundational Services (FS) require which dedicated support on some
or all network system nodes which are delivering the service
between two or more application system nodes. FS cannot be
decomposed into other services. For example, IP packet routing
and forwarding are is a (pre-existing) foundational network
services.
o Compound Services (CS) are composed of one or more foundational
services. CS are "convenience services" that make network
services easier to consume by certain applications or categories
of use cases, but do not by themselves introduce new network
services or requirements into network system nodes. One example
would be a Tactile Internet Service which consists of two
communications channels, one for tactile control and the other for
haptic feedback.
The following sections focus on Foundational Services only, as these
are the ones that provide the basic building blocks with which the
needs of all other services can be addressed, and which are the ones
that potentially introduce new foundational requirements on network
system nodes.
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8.1.1. High-Precision Communications Services
High-Precision Communications Services refers to services that have
precisely defined service level objectives related to end-to-end
latency, in many cases coupled with stringent requirements regarding
to packet loss and to bandwidth needs. These requirements are in
stark contrast to the best effort nature with related to existing
network services.
Of course, existing services often go to great lengths in order to
optimize service levels and minimize latency, and QoS techniques aim
to mitigate adverse effects of e.g. congestion by applying various
forms of prioritization and admission control. However,
fundamentally all of these techniques still constitute patches that,
while alleviating the symptoms of the underlying best-effort nature,
do not address the underlying cause and fall short of providing
service level guarantees that will not be just of a statistical
nature but that will be met by design.
The high-precision communications services that have been identified
are described in the following three sub-sections.
8.1.2. In-time Services
In-time services require end-to-end latency within a quantifiable
limit. They specific a service level objective that is not to be
exceeded, such as a maximum acceptable latency (putting a hard
boundary on the worst case). In-time services are required by
applications and use cases that have clear bounds on acceptable
latency, beyond which the Quality of Experience would deteriorate
rapidly, rendering the application unusable. An example concerns use
cases that involve providing tactile feedback to users. Creating an
illusion of touch requires a control loop with a hard-bounded round-
trip time that is determined by human / biological factors, beyond
which the sense of touch is lost and with it the ability to e.g.
operate a piece of machinery from remote. Because many such use
cases are mission-critical (such as tele-driving or remote surgery),
in addition any loss or need for retransmission is unacceptable.
This service is similar to the service provided by DetNet [RFC8655]
but with more demanding applications which need to be satisfied over
IP.
8.1.3. On-time Services
On-time services require end-to-end-latency to be of an exact
duration, with the possibility of a small quantifiable variance as
can be specified either by an acceptable window around the targeted
latency or by a lower bound in addition to an upper bound. Examples
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of use cases include applications that require synchronization
between multiple flows that have the same in-time latency target, or
applications requiring fairness between multiple participants
regardless of path lengths, such as gaming or market exchanges when
required by regulatory authorities. The concept of a lowest
acceptable latency imposes new requirements on networks to
potentially slow down packets by buffering or other means, which
introduces challenges due to high data rates and the cost e.g. of
associated memory.
8.1.4. Coordinated Services
Coordinated services require multiple interdependent flows to be
delivered with the same end-to-end latency, regardless of any
(potential additional) service level objective. Use cases and
applications include applications that require synchronization
between multiple flows, such as use cases involving data streams from
multiple cameras and telemetry sources. In the special case where an
on-time service is required, no additional service is needed (as
synchronization occurs by virtue of the fact that each flow adheres
to the same SLO), but coordination may also be required in cases
where no specific end-to-end latency is required, as long as all
flows are serviced with service levels that are identical.
8.1.5. Qualitative Communication Services
Qualitative communication services (QCS) are able to suppress
retransmission of portions of the payload that are deemed less
relevant when necessary in order to meet requirements on latency by
applications that are tolerant of certain quality degradation. They
may involve the application of network coding schemes.
QCS is a new service type that is needed to support AR/VR,
holographic-type communications Industrial Internet and services such
as autonomous driving. This needs the support of a new network
capability that is as yet to be developed.
8.2. New Capabilities
[NET2030SubG2] identifies also a number of network capabilities that
will become increasingly important going forward, in addition to the
support for any particular services. These were introduced in
Section 4.2. A number of these capabilities need to be taken into
consideration from the very beginning when thinking about how future
data-planes need to evolve.
While many of those capabilities are well known, the past has shown
that retrofitting data-planes with such capabilities after the fact
and in a way that is adequate to the problem at hand is very hard.
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8.2.1. Manage ability
Many of the services that need to be supported in the future have in
common that they place very high demands on latency and precision
that need to be supported at very high scales, coupled with
expectations of zero packet loss and much higher availability than
today.
In order to assure in-time and on-time services with high levels of
accuracy, advances in measurements and telemetry will be required in
order to monitor and validate that promised service levels are indeed
being delivered. This requires advanced instrumentation that is
ideally built-in all the way to the protocol level.
For example, the ability to identify and automatically eliminate
potential sources of service-level degradations and fluctuations will
become of increasing importance. This requires the ability to
generate corresponding telemetry data and the ability to observe the
performance of packets as they traverse the network. Some of the
challenges that need to be addressed include the very high volume of
data that gets generated and needs to be assessed, and the effects of
the collection itself on performance. In general, greater emphasis
will need to be placed on the ability to monitor, observe, and
validate packet performance and behavior than is the case today. For
seamless support, these capabilities will be inherently integrated
with the forwarding function itself, for example delivered together
with the packets. Today's solution approach, IOAM, is a promising
technology currently that points in the right direction, and that
also highlights some of the challenges - from MTU considerations due
to extending packet sizes to the ability to customize and obtain the
"right" data. It will therefore be not sufficient by itself. Data
to be generated from the network will need to be "smarter", i.e. more
insightful and action-able. This will require additional abilities
to process data "on-device". In additional, the need for new
management functions may arise, such as functions that allow to
validate adherence with agreed-upon service levels for a flow as a
whole, and to prevent data or privacy leakage as well as provide
evidence for the possibility or absence of such leakage.
8.2.2. High Programmability and Agile Life-cycle
Operators need to be able to rapidly introduce new network services
and adapt to new contexts and application needs. This will require
advances in network programmability. Today's model of vendor-defined
(supporting service features via new firmware or hardware-based
networking features) or operator-defined (supporting service features
via programmable software-defined networking (SDN) controllers,
virtualized network functions (VNF) and Network Function
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Virtualization (NFV), and service function chaining (SFC) will no
longer be sufficient.
Software Defined Networking and Network Function Virtualization (NFV)
have opened up the possibility to accelerate development life-cycles
and enable network providers to develop new networking features on
their own if needed. Segment Routing is being evolved for that
purpose as well. Furthermore, network slicing promises more agility
in the introduction of new network services. However, the complexity
of the associated controller software results in its own challenges
with software development cycles that, while more agile than life-
cycles before, are still prohibitive and that can only be undertaken
by network providers, not by their customers. Rapid customization of
networking services for specific needs or adaptation to unique
deployments are out of reach for network provider customers. What is
lacking is the ability for applications to rapidly introduce and
customize novel behavior at the network flow level, without need to
introduce application-level over-the-top (OTT) overlays. Such a
capability would be analogous to server-less computing that is
revolutionizing cloud services today. In addition, it should be
noted that softwarized networks are built on relatively stable (and
slowly evolving) underlying physical commodity hardware network
infrastructure. This is insufficient to deliver on new high-
precision network services, which require hardware advances at many
levels to provide programmable flow and QoS behavior at line rate,
affecting everything from queuing and scheduling to packet processing
pipelines.
The evolution of forwarding planes should allow development life-
cycles that are much more agile than today and move from "Dev Ops" to
"Flow Ops" (i.e. dynamic programmability of networks at the flow
level).
This requires support of novel network and data-plane programming
models which can possibly be delivered and effected via the
forwarding plane itself.
8.2.3. Security
The possibility of security threats increases with complexity of
networks, the potential ramifications of attacks are growing more
serious with increasing mission-criticality of networking services
and applications.
The forwarding plane plays a large role in the ability to thwart
attacks.
For example, the fact that source addresses are not authenticated in
existing IP is at the root of a wide range security problems from
phishing and fraudulent impersonation designed to compromise and
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steal user assets to amplification attacks designed to bring down
services.
Going forward, it is absolutely critical, then, to minimize the
attack surface of the forwarding plane as it evolves.
A key security aspects needed from the network point of view includes
to verify if the packet is authorized to enter into the network and
if it is sufficiently integrity protected. However, when packets are
emitted from the host for these new communication services, the
network portion of the packet (e.g., an extension header or an
overlay header) should not be encrypted because network nodes may
need to interpret the header and provide the desired service.
Lack of encryption and integrity validation, of course, would at the
same time increase the threat surface and open up the possibility for
attacks.
Mechanisms for authorization and integrity protection must be
developed to meet the line rate performance as services delivered can
be time sensitive. At the same time, the size of packets should not
be significantly increased to avoid negative impact on utilization
and overhead tax.
This limits the options for additional security collateral that can
be included with packets.
Homomorphic forms of encryption may need to be devised in which
network operations can be performed in privacy-preserving manner on
encrypted packet headers and tunneled packets without exposing any of
their contents.
Another dimension to security arises when the end to end service that
needs to be delivered crosses the administrative boundary of the
originating host. For those cases, additional mechanisms need to be
specified to sufficiently ensure the privacy and confidentiality of
the network layer information. While there are lot of avenues to
tackle these issues and some aspects are being looked into by various
Standards Development Organizations, e.g. IRTF PANRG on Path-Aware
Networking, comprehensive solutions are yet to be worked out.
Any mechanisms specified for authorization, integrity protection, and
network header confidentiality should be orthogonal to the transport
layer and above transport layer security mechanisms set in place by
the end host/user. Regardless of whether or not the latest security
advances in transport and layers above (e.g. TLS1.3, QUIC or HTTPSx)
are applied on the payload, network nodes should not have to act on
this information to deliver new services to avoid layer violations.
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8.2.4. Trustworthiness
As future network services are deployed, deployment scenarios will
include cases in which packets need to traverse trust boundaries
which are under different administrative domains. As the forwarding
plane evolves, it should do so in such a way that trustworthiness of
packets is maintained - i.e. integrity of data is protected,
tampering with packet meta-data (such as source authentication or
service level telemetry) would be evident, and privacy of users is
guarded.
8.2.5. Resilience
Ultra-low-latency requirements and the huge increase of bandwidth
demands of new services such as holographic type communication
services make retransmission as a mechanism to recover data that was
lost in transit increasingly less feasible. Therefore, network
resilience and avoidance of loss becomes of paramount importance.
There are many methods for providing network resilience. This
includes providing redundancy and diversity of both physical (e.g.
ports, routers, line cards) and logical (e.g. shapers, policers,
classifiers) entities. It also includes the use of protocols that
provide quick re-convergence and maintain high availability of
existing connections after a failure event occurs in the network.
Other techniques include packet replication or network coding and
error correction techniques to overcome packet loss.
As the forwarding plane evolves, mechanisms to provide network
resilience should be inherently supported.
8.2.6. Privacy-Sensitive
Today, there is a growing awareness of the lack of privacy in the
Internet and its implications.
New network services have to be sensitive to and comply with
heightened user privacy expectations.
At the same time, the need for privacy needs to be balanced with
legitimate needs of network providers to operate and maintain their
networks, which requires some visibility into what is happening on
the network and how it is being used.
Likewise, mechanisms to provide privacy must be provided in such a
way to not compromise security, such as allowing anonymous attackers
to prey on other users.
An evolved forwarding plane must provide mechanisms that ensure users
privacy by design and prevent illegitimate exposing of personally-
identifiable information (PII), while preventing abuse of those
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mechanisms by attack exploits and while affording network providers
with legitimate visibility into use of their network and services.
There are a variety of privacy-related requirements that ensue, such
as:
o Anonymization: To prevent tracking by eavesdropper by packet
capture, visible information in packets such as source and
destination addresses should be difficult (ideally: impossible) to
directly correlate to PII.
o Opaque User data: Networks must not rely on the user data to
provide or improve the service. However, network providers may
use specific service-visible data in packets.
o Secured Storage: Some services may require the network to slow
down the delivery of the packets, implying the possibility that
packets are temporarily buffered on the router. The storage of
those packets must be secured and prevented from extraction for
deep inspection or analysis.
o Flow anonymization: Flows of information should be randomized in a
dynamic manner so that it is difficult through traffic analysis to
deduce patterns and identify the type of traffic.
Potential mechanisms to consider include (but are not limited to)
avoiding the need for long-lived addresses (to prevent trackablity)
and the use of homomorphic encryption for packet headers and tunneled
packets (in addition to traditional payload encryption) that allow to
perform network operations in privacy-preserving manner without
exposing meta-data carried in headers.
8.2.7. Accountability and Verifiability
Many new services demand guarantees instead of being accepting of
"best effort".
As a result, today's "best effort" accounting may no longer be
sufficient.
Today's accounting technology largely relies on interface statistics
and flow records.
Those statistics and records may not be entirely accurate.
For example, in many cases their generation involves sampling and is
thus subject to sampling inaccuracies.
In addition, this data largely accounts for volume but not so much
for actual service levels (e.g. latencies, let alone coordination
across flows) that are delivered.
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Service level measurements can be used to complement other statistics
but come with significant overhead and also have various limitations,
from sampling to the consumption of network and edge node processing
bandwidth.
Techniques that rely on passive measurements are infeasible in many
network deployments and hampered by encryption as well as issues
relating to privacy.
Guarantees demand their price. This makes it increasingly important
both for providers and users of services to be able to validate that
promised service levels were delivered on.
For example, proof of service delivery (including proof of service
level delivery) may need to be provided to account and charge for
network services.
This will require advances in accounting technology that should be
considered as forwarding technology evolves, possibly providing
accounting as a function that is intrinsically coupled with
forwarding itself.
9. Informative References
[DOT] Huston, G., "The Death of Transit and Beyond", n.d.,
<https://hknog.net/wp-content/uploads/2018/03/01_GeoffHust
on_TheDeath_of_Transit_and_Beyond.pdf>.
[FGNETWORK2030]
"Focus Group on Technologies for Network 2030", n.d.,
<https://www.itu.int/en/ITU-T/focusgroups/net2030/Pages/
default.aspx>.
[Handley] Handley, M., "Delay is Not an Option: Low Latency Routing
in Space", n.d.,
<http://nrg.cs.ucl.ac.uk/mjh/starlink-draft.pdf>.
[I-D.bryant-arch-fwd-layer-ps]
Bryant, S., Chunduri, U., Eckert, T., and A. Clemm,
"Forwarding Layer Problem Statement", draft-bryant-arch-
fwd-layer-ps-00 (work in progress), March 2020.
[I-D.carpenter-limited-domains]
Carpenter, B. and B. Liu, "Limited Domains and Internet
Protocols", draft-carpenter-limited-domains-13 (work in
progress), February 2020.
[I-D.ietf-detnet-security]
Mizrahi, T. and E. Grossman, "Deterministic Networking
(DetNet) Security Considerations", draft-ietf-detnet-
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[I-D.ietf-teas-enhanced-vpn]
Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A
Framework for Enhanced Virtual Private Networks (VPN+)
Services", draft-ietf-teas-enhanced-vpn-05 (work in
progress), February 2020.
[NET2030SubG1]
ITU-T FGNet2030, "FG NET-2030 Sub-G1 Representative use
cases and key network requirements for Network 2030",
January 2021,
<http://handle.itu.int/11.1002/pub/815125f5-en>.
[NET2030SubG2]
ITU-T FGNET2030, "New Services and Capabilities for
Network 2030: Description, Technical Gap and Performance
Target Analysis", October 2019, <https://www.itu.int/en/
ITU-T/focusgroups/net2030/Documents/
Deliverable_NET2030.pdf>.
[RFC8578] Grossman, E., Ed., "Deterministic Networking Use Cases",
RFC 8578, DOI 10.17487/RFC8578, May 2019,
<https://www.rfc-editor.org/info/rfc8578>.
[RFC8655] Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", RFC 8655,
DOI 10.17487/RFC8655, October 2019,
<https://www.rfc-editor.org/info/rfc8655>.
[SysArch5G]
"System architecture for the 5G System (5GS)", n.d.,
<https://portal.3gpp.org/desktopmodules/Specifications/
SpecificationDetails.aspx?specificationId=3144>.
[UC] ITU-T FGNET2030, "Use Cases and Requirements for Network
2030 Summary report "Representative use cases and key
network requirements for Network 2030"", January 2020,
<https://www.itu.int/en/ITU-
T/focusgroups/net2030/Documents/Technical_Report.pdf>.
[WP] "Network 2030 - A Blueprint of Technology, Applications,
and Market Drivers towards the Year 2030 and Beyond, a
White Paper on Network 2030, ITU-T", May 2019,
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T/focusgroups/net2030/Documents/White_Paper.pdf>.
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Authors' Addresses
Stewart Bryant
Futurewei Technologies Inc.
Email: sb@stewartbryant.com
Uma Chunduri
Futurewei Technologies Inc.
Email: uma.chunduri@futurewei.com
Toerless Eckert
Futurewei Technologies Inc.
Email: tte@cs.fau.de
Alexander Clemm
Futurewei Technologies Inc.
Email: ludwig@clemm.org
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