Page 114 - Kaleidoscope Academic Conference Proceedings 2021

2021 ITU Kaleidoscope Academic Conference

It is essential to prevent the common tracking at application ensure a bounded latency and low data loss rates within
level due to the locator-based addressing being used at the a single network domain.
routing layer, addressing the needed locator and identity split Making use of three distinct techniques, the DetNet
as well as the denial-of-service potential that the reliance on architecture aims to provide per-flow service guarantees
locator-based addressing brings. in terms of maximum end-to-end latency (called bounded
delay in DetNet) and bounded jitter, packet loss ratio, and
The decoupling of the locator addressing from the user an upper bound on out-of-order packet delivery. Some
identification at routing level (and usage of ephemeral options considered in DetNet may in the future also be
routing identifiers) can make long term tracking of users able to provide bounded delay-variation between packets
impossible. Denial-of-service prevention can be also enabled of flows.
through removal of the coupling of user identity to the Scalability remains a challenge as DetNet does not
ephemeral locator based on signaling [1]. change the existing data plane, and is actually limited by
it, specifically constraining the study to autonomous
Additional mechanisms need to be specified to sufficiently system-internal mechanisms. Data plane scalability
ensure the privacy and confidentiality of the network layer issues concern the need to keep track of per-flow state
information with respect to end-to-end services that need to and to implement advanced traffic shaping and packet
be delivered across the administrative boundary of the scheduling schemes at every hop.
originating host. Like IntServ, DetNet targets CBR reservations.
4. THE NEED OF FURTHER NETWORK Further research is needed, but not limited to enabling the
RESEARCH AND STANDARDIZATION IN development of technologies that can be both effective in
SUPPORT TO FUTURE INDUSTRIAL ensuring deterministic latency for all types of traffic (not just
APPLICATIONS at constant bit rates) and scalable to support a large number
of simultaneous flows.
Further research studies and standardization efforts are
required in terms of network technologies to enhance the As far as the network support of flexible addressing and
network with new capabilities addressing the network routing, there is evidence that further research studies and
requirements of emerging and future industrial applications. standardization efforts are needed too:

With respect to the three networking technology areas While it is recognized that semantic addressing may help to
identified in Section 3, this section provides an overview of facilitate addressing and routing within networks, scalability
the relevant research studies and/or standards development challenges arise from providing the definition of those
efforts up to present time, highlighting their limitations semantics, and the interconnection among such networks and
towards the identified requirements. the Internet. Several techniques have been proposed to
improve the default IP forwarding behaviors in order to
As far as the network support of time-deterministic better meet the application requirements [28], however those
capabilities on a large scale, it is presently not addressed by solutions have been developed in a fragmented way, with
the main concerned standardization activities: interoperability issues between limited domains or between
 The IEEE Ethernet standard has been enriched with the individual routers, and the possibility of increased fragility
Time-Sensitive Networking (TSN) [24] [25] set of or even security and privacy leakage. As far as the
updates aiming to empower standard Ethernet with time Information-Centric Networking (ICN) technology area, it is
synchronization and deterministic communication now reaching maturity, but limited semantic-based
capabilities. From the viewpoint of latency control, TSN networking support is enabled (Content Routing and Name
can be considered as an Ethernet layer 2 variation of the Data Networking based reachability), and the technical
IntServ service [26] supporting the enhancements of discussion into the deployment and operation of ICNs still
802.1QCH (cyclic queuing) for deterministic shaping continues in IETF.
without per-flow state on transit nodes, and 802.1CB  A more holistic approach is needed for architectural
(frame replication and elimination for reliability) for pro- patterns and common building blocks based on semantic
active path protection. routing [29].
TSN aims to provide a deterministic service inside a  As illustrated in Section 3, flexible length addressing can
LAN over a short distance, and is thus not routing- also bring value in a number of application scenarios.
capable. TSN does not aim to provide on-time guaranteed While being currently implemented in an increasing
service over large-scale networks and over longer number of limited domain deployments, it has not yet
distances. Like IntServ, TSN is geared towards Constant found its way in standardization.
Bit Rate (CBR) traffic, while future applications may  Changes to the IP address semantics and support of
have highly Variable Bit Rates (VBR). flexible length addressing imply challenges to the routing
 The deterministic networking architecture (DetNet) [27] system [28]. Routing advances should devise an
proposed by the IETF DetNet Working Group aims to integrated, flexible, hierarchical addressing scheme for
the routing layer, enabling backwards compatibility with

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