Deterministic Networking
charter-ietf-detnet-02

The Deterministic Networking (DetNet) Working Group focuses on deterministic data paths that operate over Layer 2 bridged and Layer 3 routed segments, where such paths can provide bounds on latency, loss, and packet delay variation (jitter), and high reliability. The Working Group addresses Layer 3 aspects in support of applications requiring deterministic networking. The Working Group collaborates with IEEE802.1 Time-Sensitive Networking (TSN), which is responsible for Layer 2 operations, to define a common architecture for both Layer 2 and Layer 3. Example applications for deterministic networks include professional and home audio/video, multimedia in transportation, engine control systems, and other general industrial and vehicular applications being considered by the IEEE 802.1 TSN Task Group.

The Working Group will initially focus on solutions for networks that are under a single administrative control or within a closed group of administrative control; these include not only campus-wide networks but also can include private WANs. The DetNet WG will not spend energy on solutions for large groups of domains such as the Internet.

The Working Group is responsible for the overall DetNet architecture and
DetNet-specific specifications that encompasses the data plane, OAM
(Operations, Administration, and Maintenance), time synchronization,
management, control, and security aspects which are required to enable a
multi-hop path, and forwarding along the path, with the deterministic
properties of controlled latency, low packet loss, low packet delay
variation, and high reliability. The work applies to point-to-point
(unicast) and point-to-multipoint (multicast) flows which can be
characterized in a manner that allows the network to 1) reserve the
appropriate resources for the flows in advance, and 2) release/reuse the
resources when they are no longer required. The work covers the
characterization of flows, the encapsulation of frames, the required
forwarding behaviors, as well as the state that may need to be
established in intermediate nodes. Layer 3 data plane technologies that
can be used include: IP and MPLS, and Layer 2 encapsulations that run
over IP and/or MPLS, such as pseudowires and GRE.

The Working Group will document which deployment environments and types
of topologies are within (or outside) the scope of the DetNet
architecture. This work focuses on the data plane aspects and is
independent from any path setup protocol or mechanism. The Working Group
will also document DetNet Controller Plane approaches that reuse
existing IETF solutions, such as Path Computation Element (PCE), and
identify the Working Group responsible for any extensions needed to
support DetNet. Documents produced by the Working Group will be
compatible with the work done in IEEE802.1 TSN and other IETF Working
Groups. The Working Group's scope explicitly excludes modifications of
transport protocols, OAM, Layer 3 forwarding, and encapsulations, but
it may discuss requirements for such modifications and the work will be
done in the Working Group responsible for the technology.

DetNet is chartered to work in the following areas:

Overall architecture: This work encompasses the data plane, OAM,
time synchronization, management, control, and security aspects.

Data plane: This work will document how to use IP and/or MPLS, and
related OAM, to support a data plane method of flow identification
and packet forwarding over Layer 3. Other IETF defined data plane
technologies may also be used.

Controller Plane: The DetNet Controller Plane is defined in RFC 8655
as "the aggregation of the Control and Management Planes". This work
will document how to use IETF control plane solutions to support DetNet,
including the identification of any gaps in existing solutions. Any
modification to Controller Plane protocols to address identified gaps
should be carried out in their associated Working Groups, but may be done
in DetNet if agreed to by the relevant Working Group chairs and responsible
Area Directors.

Data flow information model: This work will identify the information
needed for flow establishment and control and be used by reservation
protocols and YANG data models. The work will be independent from
the protocol(s) used to control the flows (e.g. YANG+NETCONF/RESTCONF,
PCEP or GMPLS).

YANG models: This work will document device and link capabilities
(feature support) and resources (e.g. buffers, bandwidth) for use in
device configuration and status reporting. Such information may also
be used when advertising the deterministic network elements to a
control plane. Control plane related information will be independent
from the protocol(s) which may be used to advertise this information
(e.g. IS-IS or GMPLS extensions). Any new YANG models will be
coordinated with the Working Groups that define any base models that
are to be augmented.

As needed, vertical requirements: This effort will detail the
requirements for deterministic networks in various industries that
have previously not been documented and cannot be supported using
defined DetNet solutions.

To investigate whether existing data plane encryption mechanisms can
be applied, possibly opportunistically, to improve security and
privacy.

The Working Group coordinates with other relevant IETF Working Groups,
including CCAMP, IPPM, LSR, PCE, PALS, TEAS, TSVWG, RAW, and
6TiSCH. As the work progresses, requirements may be provided to the
responsible Working Group, e.g. PCE, TEAS, and CCAMP, with DetNet acting
as a focal point to maintain the consistency of the overall architecture
and related solutions. The WG will liaise with appropriate groups in
IEEE and other Standards Development Organizations (SDOs).