< draft-finn-detnet-bounded-latency-01.txt		draft-finn-detnet-bounded-latency-02.txt >
	DetNet N. Finn		DetNet N. Finn
	Internet-Draft Huawei Technologies Co. Ltd		Internet-Draft Huawei Technologies Co. Ltd
	Intended status: Standards Track J-Y. Le Boudec		Intended status: Standards Track J-Y. Le Boudec
	Expires: January 3, 2019 E. Mohammadpour		Expires: April 25, 2019 E. Mohammadpour
	EPFL		EPFL
			J. Zhang
			Huawei Technologies Co. Ltd
	B. Varga		B. Varga
	J. Farkas		J. Farkas
	Ericsson		Ericsson
	July 2, 2018		October 22, 2018
	DetNet Bounded Latency		DetNet Bounded Latency
	draft-finn-detnet-bounded-latency-01		draft-finn-detnet-bounded-latency-02
	Abstract		Abstract
	This document presents a parameterized timing model for Deterministic		This document presents a parameterized timing model for Deterministic
	Networking so that existing and future standards can achieve bounded		Networking (DetNet), so that existing and future standards can
	latency and zero congestion loss.		achieve the DetNet quality of service features of bounded latency and
			zero congestion loss. It defines requirements for resource
			reservation protocols or servers. It calls out queuing mechanisms,
			defined in other documents, that can provide the DetNet quality of
			service.
	Status of This Memo		Status of This Memo
	This Internet-Draft is submitted in full conformance with the		This Internet-Draft is submitted in full conformance with the
	provisions of BCP 78 and BCP 79.		provisions of BCP 78 and BCP 79.
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
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	Copyright Notice		Copyright Notice
	Copyright (c) 2018 IETF Trust and the persons identified as the		Copyright (c) 2018 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
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	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
	2. Conventions Used in This Document . . . . . . . . . . . . . . 3		2. Conventions Used in This Document . . . . . . . . . . . . . . 4
	3. Terminology and Definitions . . . . . . . . . . . . . . . . . 4		3. Terminology and Definitions . . . . . . . . . . . . . . . . . 4
	4. DetNet bounded latency model . . . . . . . . . . . . . . . . 4		4. DetNet bounded latency model . . . . . . . . . . . . . . . . 4
	4.1. Flow creation . . . . . . . . . . . . . . . . . . . . . . 4		4.1. Flow creation . . . . . . . . . . . . . . . . . . . . . . 4
	4.2. End-to-end model . . . . . . . . . . . . . . . . . . . . 5		4.2. Relay system model . . . . . . . . . . . . . . . . . . . 5
	4.3. Relay system model . . . . . . . . . . . . . . . . . . . 5
	5. Computing End-to-end Latency Bounds . . . . . . . . . . . . . 7		5. Computing End-to-end Latency Bounds . . . . . . . . . . . . . 7
	5.1. Examples of Computations . . . . . . . . . . . . . . . . 8		5.1. Non-queuing delay bound . . . . . . . . . . . . . . . . . 7
	5.1.1. Per-flow queuing . . . . . . . . . . . . . . . . . . 8		5.2. Queuing delay bound . . . . . . . . . . . . . . . . . . . 8
	5.1.2. Time-Sensitive Networking with Asynchronous Traffic		5.2.1. Per-flow queuing mechanisms . . . . . . . . . . . . . 8
	Shaping . . . . . . . . . . . . . . . . . . . . . . . 8		5.2.2. Per-class queuing mechanisms . . . . . . . . . . . . 8
	6. Achieving zero congestion loss . . . . . . . . . . . . . . . 9		6. Achieving zero congestion loss . . . . . . . . . . . . . . . 10
	6.1. A General Formula . . . . . . . . . . . . . . . . . . . . 9		6.1. A General Formula . . . . . . . . . . . . . . . . . . . . 10
	7. Queuing model . . . . . . . . . . . . . . . . . . . . . . . . 10		7. Queuing model . . . . . . . . . . . . . . . . . . . . . . . . 11
	7.1. Queuing data model . . . . . . . . . . . . . . . . . . . 10		7.1. Queuing data model . . . . . . . . . . . . . . . . . . . 11
	7.2. IEEE 802.1 Queuing Model . . . . . . . . . . . . . . . . 12		7.2. Preemption . . . . . . . . . . . . . . . . . . . . . . . 13
	7.2.1. Queuing Data Model with Preemption . . . . . . . . . 12		7.3. Time-scheduled queuing . . . . . . . . . . . . . . . . . 13
	7.2.2. Transmission Selection Model . . . . . . . . . . . . 13		7.4. Time-Sensitive Networking with Asynchronous Traffic
	7.3. Time-Sensitive Networking with Asynchronous Traffic		Shaping . . . . . . . . . . . . . . . . . . . . . . . . . 13
	Shaping . . . . . . . . . . . . . . . . . . . . . . . . . 15		7.5. IntServ . . . . . . . . . . . . . . . . . . . . . . . . . 15
	7.4. Other queuing models, e.g. IntServ . . . . . . . . . . . 17		8. Time-based DetNet QoS . . . . . . . . . . . . . . . . . . . . 19
	8. Parameters for the bounded latency model . . . . . . . . . . 17		8.1. Cyclic Queuing and Forwarding . . . . . . . . . . . . . . 19
	8.1. Sender parameters . . . . . . . . . . . . . . . . . . . . 17		8.2. Time Scheduled Queuing . . . . . . . . . . . . . . . . . 19
	8.2. Relay system parameters . . . . . . . . . . . . . . . . . 17		9. Parameters for the bounded latency model . . . . . . . . . . 20
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . 17		9.1. Sender parameters . . . . . . . . . . . . . . . . . . . . 20
	9.1. Normative References . . . . . . . . . . . . . . . . . . 17		9.2. Relay system parameters . . . . . . . . . . . . . . . . . 21
	9.2. Informative References . . . . . . . . . . . . . . . . . 18		10. References . . . . . . . . . . . . . . . . . . . . . . . . . 21
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20		10.1. Normative References . . . . . . . . . . . . . . . . . . 21
			10.2. Informative References . . . . . . . . . . . . . . . . . 22
			Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23
	1. Introduction		1. Introduction
	The ability for IETF Deterministic Networking (DetNet) or IEEE 802.1		The ability for IETF Deterministic Networking (DetNet) or IEEE 802.1
	Time-Sensitive Networking (TSN) to provide the DetNet services of		Time-Sensitive Networking (TSN, [IEEE8021TSN]) to provide the DetNet
	bounded latency and zero congestion loss depends upon A) configuring		services of bounded latency and zero congestion loss depends upon A)
	and allocating network resources for the exclusive use of DetNet/TSN		configuring and allocating network resources for the exclusive use of
	flows; B) identifying, in the data plane, the resources to be		DetNet/TSN flows; B) identifying, in the data plane, the resources to
	utilized by any given packet, and C) the detailed behavior of those		be utilized by any given packet, and C) the detailed behavior of
	resources, especially transmission queue selection, so that latency		those resources, especially transmission queue selection, so that
	bounds can be reliably assured. Thus, DetNet is an example of an		latency bounds can be reliably assured. Thus, DetNet is an example
	INTSERV Guaranteed Quality of Service [RFC2212]		of an INTSERV Guaranteed Quality of Service [RFC2212]
	As explained in [I-D.ietf-detnet-architecture], DetNet flows are		As explained in [I-D.ietf-detnet-architecture], DetNet flows are
	characterized by 1) a maximum bandwidth, guaranteed either by the		characterized by 1) a maximum bandwidth, guaranteed either by the
	transmitter or by strict input metering; and 2) a requirement for a		transmitter or by strict input metering; and 2) a requirement for a
	guaranteed worst-case end-to-end latency. That latency guarantee, in		guaranteed worst-case end-to-end latency. That latency guarantee, in
	turn, provides the opportunity for the network to supply enough		turn, provides the opportunity for the network to supply enough
	buffer space to guarantee zero congestion loss. To be of use to the		buffer space to guarantee zero congestion loss. To be of use to the
	applications identified in [I-D.ietf-detnet-use-cases], it must be		applications identified in [I-D.ietf-detnet-use-cases], it must be
	possible to calculate, before the transmission of a DetNet flow		possible to calculate, before the transmission of a DetNet flow
	commences, both the worst-case end-to-end network latency, and the		commences, both the worst-case end-to-end network latency, and the
	amount of buffer space required at each hop to ensure against		amount of buffer space required at each hop to ensure against
	congestion loss.		congestion loss.
	Rather than defining, in great detail, specific mechanisms to be used		This document references specific queuing mechanisms, defined in
	to control packet transmission at each output port, this document		other documents, that can be used to control packet transmission at
	presents a timing model for sources, destinations, and the network		each output port and achieve the DetNet qualities of service. This
	nodes that relay packets. The parameters specified in this model:		document presents a timing model for sources, destinations, and the
			network nodes that relay packets that is applicable to all of those
			referenced queuing mechanisms. The parameters specified in this
			model:
	o Characterize a DetNet flow in a way that provides externally		o Characterize a DetNet flow in a way that provides externally
	measureable verification that the sender is conforming to its		measurable verification that the sender is conforming to its
	promised maximum, can be implemented reasonably easily by a		promised maximum, can be implemented reasonably easily by a
	sending device, and does not require excessive over-allocation of		sending device, and does not require excessive over-allocation of
	resources by the network.		resources by the network.
	o Enable resonably accurate computation of worst-case end-to-end		o Enable reasonably accurate computation of worst-case end-to-end
	latency, in a way that requires as little detailed knowledge as		latency, in a way that requires as little detailed knowledge as
	possible of the behavior of the Quality of Service (QoS)		possible of the behavior of the Quality of Service (QoS)
	algorithms implemented in each devince, including queuing,		algorithms implemented in each device, including queuing, shaping,
	shaping, metering, policing, and transmission selection		metering, policing, and transmission selection techniques.
	techniques.
	Using the model presented in this document, it should be possible for		Using the model presented in this document, it should be possible for
	an implementor, user, or standards development organization to select		an implementor, user, or standards development organization to select
	a particular set of QoS algorithms for each device in a DetNet		a particular set of queuing mechanisms for each device in a DetNet
	network, and to select a resource reservation algorithm for that		network, and to select a resource reservation algorithm for that
	network, so that those elements can work together to provide the		network, so that those elements can work together to provide the
	DetNet service.		DetNet service.
	This document does not specify any resource reservation protocol or		This document does not specify any resource reservation protocol or
	server. It does not describe all of the requirements for that		server. It does not describe all of the requirements for that
	protocol or server. It does describe a set of requirements for		protocol or server. It does describe requirements for such resource
	resource reservation algorithms and for QoS algorithms that, if met,		reservation methods, and for queuing mechanisms that, if met, will
	will enable them to work together.		enable them to work together.
			NOTE: This draft is not yet complete, but it is sufficiently so to
			share with the Working Group and to obtain opinions and direction.
			The present intent of is for this draft to become a normative RFC,
			defining how one SHALL/SHOULD provide the DetNet quality of service.
			There are still a few authors' notes to each other present in this
			draft.
	2. Conventions Used in This Document		2. Conventions Used in This Document
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",		The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in [RFC2119].		document are to be interpreted as described in [RFC2119].
	The lowercase forms with an initial capital "Must", "Must Not",		The lowercase forms with an initial capital "Must", "Must Not",
	"Shall", "Shall Not", "Should", "Should Not", "May", and "Optional"		"Shall", "Shall Not", "Should", "Should Not", "May", and "Optional"
	in this document are to be interpreted in the sense defined in		in this document are to be interpreted in the sense defined in
	skipping to change at page 4, line 20 ¶		skipping to change at page 4, line 36 ¶
	3. Terminology and Definitions		3. Terminology and Definitions
	This document uses the terms defined in		This document uses the terms defined in
	[I-D.ietf-detnet-architecture].		[I-D.ietf-detnet-architecture].
	4. DetNet bounded latency model		4. DetNet bounded latency model
	4.1. Flow creation		4.1. Flow creation
	The bounded latency model assusmes the use of the following paradigm		The bounded latency model assumes the use of the following paradigm
	for provisioning a particular DetNet flow:		for provisioning a particular DetNet flow:
	1. Perform any onfiguration required by the relay systems in the		1. Perform any configuration required by the relay systems in the
	network for the classes of service to be offered, including one		network for the classes of service to be offered, including one
	or more classes of DetNet service. This configuration is		or more classes of DetNet service. This configuration is not
	general; it is not tied to any particular flow.		tied to any particular flow.
	2. Characterize the DetNet flow in terms of limitations on the		2. Characterize the DetNet flow in terms of limitations on the
	sender Section 8.1 and flow requirements Section 8.2.		sender [Section 9.1] and flow requirements [Section 9.2].
	3. Establish the path that the DetNet flow will take through the		3. Establish the path that the DetNet flow will take through the
	network from the source to the destination(s). This can be a		network from the source to the destination(s). This can be a
	point-to-point or a point-to-multipoint path.		point-to-point or a point-to-multipoint path.
	4. Select one of the DetNet classes of service for the DetNet flow.		4. Select one of the DetNet classes of service for the DetNet flow.
	5. Compute the worst-case end-to-end latency for the DetNet flow.		5. Compute the worst-case end-to-end latency for the DetNet flow.
	In the process, determine whether sufficient resources are		In the process, determine whether sufficient resources are
	available for that flow to guarantee the required latency and		available for that flow to guarantee the required latency and to
	provide zero congestion loss.		provide zero congestion loss.
	6. Assuming that the resources are available, commit those resources		6. Assuming that the resources are available, commit those resources
	to the flow. This may or may not require adjusting the		to the flow. This may or may not require adjusting the
	parameters that control the QoS algorithms at each hop along the		parameters that control the queuing mechanisms at each hop along
	flow's path.		the flow's path.
	This paradigm can be static and/or dynamic, and can be implemented		This paradigm can be static and/or dynamic, and can be implemented
	using peer-to-peer protocols or with a central server model. In some		using peer-to-peer protocols or using a central server model. In
	situations, backtracking and recursing through this list may be		some situations, backtracking and recursing through this list may be
	necessary.		necessary.
	Issues such as un-provisioning a DetNet flow in favor of another when		Issues such as un-provisioning a DetNet flow in favor of another when
	resources are scarce are not considered. How the path to be taken by		resources are scarce are not considered. How the path to be taken by
	a DetNet flow is chosen is not considered in this document.		a DetNet flow is chosen is not considered in this document.
	4.2. End-to-end model		4.2. Relay system model
	[Suggestion: This is the introduction to network calculus. The
	starting point is a model in which a relay system is a black box.]
	4.3. Relay system model
	[NWF I think that at least some of this will be useful. We won't
	know until we see what J-Y has to say in Section 4.2. I'm especially
	interested in whether J-Y thinks that the "output delay" in Figure 1
	is useful in determining the number of buffers needed in the next
	hop. It is possible that we can define the parameters we need
	without this section.]
	In Figure 1 we see a breakdown of the per-hop latency experienced by		In Figure 1 we see a breakdown of the per-hop latency experienced by
	a packet passing through a relay system, in terms that are suitable		a packet passing through a relay system, in terms that are suitable
	for computing both hop-by-hop latency and per-hop buffer		for computing both hop-by-hop latency and per-hop buffer
	requirements.		requirements.
	DetNet relay node A DetNet relay node B		DetNet relay node A DetNet relay node B
	+-------------------+ +-------------------+		+-------------------------+ +------------------------+
	| Reg. Queue | | Reg. Queue |		| Queuing | | Queuing |
	| +-+-+ +-+-+-+ | | +-+-+ +-+-+-+ |		| Regulator subsystem | | Regulator subsystem |
	-->+ | | | | | | + +------->+ | | | | | | + +--->		| +-+-+-+-+ +-+-+-+-+ | | +-+-+-+-+ +-+-+-+-+ |
	| +-+-+ +-+-+-+ | | +-+-+ +-+-+-+ |		-->+ | | | | | | | | | + +------>+ | | | | | | | | | + +--->
	| | | |		| +-+-+-+-+ +-+-+-+-+ | | +-+-+-+-+ +-+-+-+-+ |
	+-------------------+ +-------------------+		| | | |
	|<->|<-->|<---->|<->|<------>|<->|<-->|<---->|<->|<--		+-------------------------+ +------------------------+
	2,3 4 5 6 1 2,3 4 5 6 1 2,3		|<->|<------>|<------->|<->|<---->|<->|<------>|<------>|<->|<--
	1: Output delay 3: Preemption delay		2,3 4 5 6 1 2,3 4 5 6 1 2,3
	2: Link delay 4: Processing delay		1: Output delay 4: Processing delay
	5: Regulation delay 6: Queuing delay.		2: Link delay 5: Regulation delay
			3: Preemption delay 6: Queuing delay.
	Figure 1: Timing model for DetNet or TSN		Figure 1: Timing model for DetNet or TSN
	In Figure 1, we see two DetNet relay nodes (typically, bridges or		In Figure 1, we see two DetNet relay nodes (typically, bridges or
	routers), with a wired link between them. In this model, the only		routers), with a wired link between them. In this model, the only
	queues we deal with explicitly are attached to the output port; other		queues we deal with explicitly are attached to the output port; other
	queues are modeled as variations in the other delay times. (E.g., an		queues are modeled as variations in the other delay times. (E.g., an
	input queue could be modeled as either a variation in the link delay		input queue could be modeled as either a variation in the link delay
	[2] or the processing delay [4].) There are five delays that a
	packet can experience from hop to hop.		[2] or the processing delay [4].) There are six delays that a packet
			can experience from hop to hop.
	1. Output delay		1. Output delay
	The time taken from the selection of a packet for output from a		The time taken from the selection of a packet for output from a
	queue to the transmission of the first bit of the packet on the		queue to the transmission of the first bit of the packet on the
	physical link. If the queue is directly attached to the physical		physical link. If the queue is directly attached to the physical
	port, output delay can be a constant. But, in many		port, output delay can be a constant. But, in many
	implementations, the queuing mechanism in a forwarding ASIC is		implementations, the queuing mechanism in a forwarding ASIC is
	separated from a multi-port MAC/PHY, in a second ASIC, by a		separated from a multi-port MAC/PHY, in a second ASIC, by a
	multiplexed connection. This causes variations in the output		multiplexed connection. This causes variations in the output
	delay that are hard for the forwarding node to predict or control.		delay that are hard for the forwarding node to predict or control.
	skipping to change at page 6, line 24 ¶		skipping to change at page 6, line 29 ¶
	The time taken from the transmission of the first bit of the		The time taken from the transmission of the first bit of the
	packet to the reception of the last bit, assuming that the		packet to the reception of the last bit, assuming that the
	transmission is not suspended by a preemption event. This delay		transmission is not suspended by a preemption event. This delay
	has two components, the first-bit-out to first-bit-in delay and		has two components, the first-bit-out to first-bit-in delay and
	the first-bit-in to last-bit-in delay that varies with packet		the first-bit-in to last-bit-in delay that varies with packet
	size. The former is typically measured by the Precision Time		size. The former is typically measured by the Precision Time
	Protocol and is constant (see [I-D.ietf-detnet-architecture]).		Protocol and is constant (see [I-D.ietf-detnet-architecture]).
	However, a virtual "link" could exhibit a variable link delay.		However, a virtual "link" could exhibit a variable link delay.
	3. Preemption delay		3. Preemption delay
	If the packet is interrupted (e.g. [IEEE8023br] preemption) in		If the packet is interrupted (e.g. [IEEE8023br] and [IEEE8021Qbu]
	order to transmit another packet or packets, an arbitrary delay		preemption) in order to transmit another packet or packets, an
	can result.		arbitrary delay can result.
	4. Processing delay		4. Processing delay
	This delay covers the time from the reception of the last bit of		This delay covers the time from the reception of the last bit of
	the packet to that packet being eligible, if there were no other		the packet to the time the packet is enqueued in the regulator
	packets in the queue, for selection for output. This delay can be		(Queuing subsystem, if there is no regulation). This delay can be
	variable, and depends on the details of the operation of the		variable, and depends on the details of the operation of the
	forwarding node.		forwarding node.
	5. Regulation delay		5. Regulator delay
	This is the time spent from the insertion of the packet into a		This is the time spent from the insertion of the last bit of a
	regulation queue until the time the packet is declared eligible		packet into a regulation queue until the time the packet is
	according to its regulation constraints. We assume that this time		declared eligible according to its regulation constraints. We
	can be calculated based on the details of regulation policy. If		assume that this time can be calculated based on the details of
	there is no regulation, this time is zero.		regulation policy. If there is no regulation, this time is zero.
	6. Queuing delay		6. Queuing subsystem delay
	This is the time spent for a packet from being declared eligibile		This is the time spent for a packet from being declared eligible
	until being selected for output on the next link. We assume that		until being selected for output on the next link. We assume that
	this time is calculable based on the details of the queuing		this time is calculable based on the details of the queuing
	mechanism. If there is no regulation, this time is from the		mechanism. If there is no regulation, this time is from the
	insertion of the packet into a queue until it is selected for		insertion of the packet into a queue until it is selected for
	output on the next link.		output on the next link.
	Not shown in Figure 1 are the other output queues that we presume are		Not shown in Figure 1 are the other output queues that we presume are
	also attached to that same output port as the queue shown, and		also attached to that same output port as the queue shown, and
	against which this shown queue competes for transmission		against which this shown queue competes for transmission
	opportunities.		opportunities.
	skipping to change at page 7, line 26 ¶		skipping to change at page 7, line 31 ¶
	delays 1-4 are not constant, then additional buffers are required in		delays 1-4 are not constant, then additional buffers are required in
	the queue to absorb these variations. Thus:		the queue to absorb these variations. Thus:
	o Variations in output delay (1) require buffers to absorb that		o Variations in output delay (1) require buffers to absorb that
	variation in the next hop, so the output delay variations of the		variation in the next hop, so the output delay variations of the
	previous hop (on each input port) must be known in order to		previous hop (on each input port) must be known in order to
	calculate the buffer space required on this hop.		calculate the buffer space required on this hop.
	o Variations in processing delay (4) require additional output		o Variations in processing delay (4) require additional output
	buffers in the queues of that same Detnet relay node. Depending		buffers in the queues of that same Detnet relay node. Depending
	on the details of the queueing delay (6) calculations, these		on the details of the queueing subsystem delay (6) calculations,
	variations need not be visible outside the DetNet relay node.		these variations need not be visible outside the DetNet relay
			node.
	5. Computing End-to-end Latency Bounds		5. Computing End-to-end Latency Bounds
			5.1. Non-queuing delay bound
	End-to-end latency bounds can be computed using the delay model in		End-to-end latency bounds can be computed using the delay model in
	Section 4.3. Here it is important to be aware that for several		Section 4.2. Here it is important to be aware that for several
	queuing mechanisms, the worst-case end-to-end delay is less than the		queuing mechanisms, the worst-case end-to-end delay is less than the
	sum of the per-hop worst-case delays. An end-to-end latency bound		sum of the per-hop worst-case delays. An end-to-end latency bound
	for one detnet flow can be computed as		for one DetNet flow can be computed as
	end_to_end_latency_bound = non_queuing_latency + queuing_latency		end_to_end_latency_bound = non_queuing_latency + queuing_latency
	The two terms in the above formula are computed as follows. First,		The two terms in the above formula are computed as follows. First,
	at the h-th hop along the path of this detnet flow, obtain an upper		at the h-th hop along the path of this DetNet flow, obtain an upper
	bound per-hop_non_queuing_latency[h] on the sum of delays 1,2,3,4 of		bound per-hop_non_queuing_latency[h] on the sum of delays 1,2,3,4 of
	Figure 1. These upper-bounds are expected to depend on the specific		Figure 1. These upper-bounds are expected to depend on the specific
	technology of the node at the h-th hop but not on the T-SPEC of this		technology of the node at the h-th hop but not on the T-SPEC of this
	detnet flow. Then set non_queuing_latency = the sum of per-		DetNet flow. Then set non_queuing_latency = the sum of per-
	hop_non_queuing_latency[h] over all hops h.		hop_non_queuing_latency[h] over all hops h.
			5.2. Queuing delay bound
	Second, compute queuing_latency as an upper bound to the sum of the		Second, compute queuing_latency as an upper bound to the sum of the
	queuing delays along the path. The value of queuing_latency depends		queuing delays along the path. The value of queuing_latency depends
	on the T-SPEC of this flow and possibly of other flows in the		on the T-SPEC of this flow and possibly of other flows in the
	network, as well as the specifics of the queuing mechanisms deployed		network, as well as the specifics of the queuing mechanisms deployed
	along the path of this flow.		along the path of this flow.
	For several queuing mechanisms, queuing_latency is less than the sum		For several queuing mechanisms, queuing_latency is less than the sum
	of upper bounds on the queuing delays (5,6) at every hop.		of upper bounds on the queuing delays (5,6) at every hop. This
	Section 5.1 gives such practical computation examples.		occurs with (1) per-flow queuing, and (2) per-class queuing with
			regulators, as explained in Section 5.2.1, Section 5.2.2, and
			Section 7.
	For other queuing mechanisms the only available value of		For other queuing mechanisms the only available value of
	queuing_latency is the sum of the per-hop queuing delay bounds. In		queuing_latency is the sum of the per-hop queuing delay bounds. In
	such cases, the computation of per-hop queuing delay bounds must		such cases, the computation of per-hop queuing delay bounds must
	account for the fact that the T-SPEC of a detnet flow is no longer		account for the fact that the T-SPEC of a DetNet flow is no longer
	satisfied at the ingress of a hop, since burstiness increases as one		satisfied at the ingress of a hop, since burstiness increases as one
	flow traverses one detnet node.		flow traverses one DetNet node.
	5.1. Examples of Computations		5.2.1. Per-flow queuing mechanisms
	5.1.1. Per-flow queuing		With such mechanisms, each flow uses a separate queue inside every
			node. The service for each queue is abstracted with a guaranteed
			rate and a delay. For every flow the per-node delay bound as well as
			end-to-end delay bound can be computed from the traffic specification
			of this flow at its source and from the values of rates and latencies
			at all nodes along its path. Details of calculation for IntServ are
			described in Section 7.5.
	[[ JYLB: THIS IS WHERE DETAILS OF END-TO-END LATENCY COMPUTATION ARE		5.2.2. Per-class queuing mechanisms
	GIVEN FOR PER-FLOW QUEUING]]
	5.1.2. Time-Sensitive Networking with Asynchronous Traffic Shaping		With such mechanisms, the flows that have the same class share the
			same queue. A practical example is the queuing mechanism in Time
			Sensitive Networking. One key issue in this context is how to deal
			with the burstiness cascade: individual flows that share a resource
			dedicated to a class may see their burstiness increase, which may in
			turn cause increased burstiness to other flows downstream of this
			resource. Computing latency upper bounds for such cases is
			difficult, and in some conditions impossible
			[charny2000delay][bennett2002delay]. Also, when bounds are obtained,
			they depend on the complete configuration, and must be recomputed
			when one flow is added.
	Figure 2 shows an example of a network with 5 nodes, which have the		A solution to deal with this issue is to reshape the flows at every
	queuing model as Section 7.3. An end-to-end delay bound for flow f		hop. This can be done with per-flow regulators (e.g. leaky bucket
	of a given AVB class (A or B), traversing from node 1 to 5, is		shapers), but this requires per-flow queuing and defeats the purpose
	calculated as following:		of per-class queuing. An alternative is the interleaved regulator,
			which reshapes individual flows without per-flow queuing
			([Specht2016UBS], [IEEE8021Qcr]"). With an interleaved regulator,
			the packet at the head of the queue is regulated based on its (flow)
			regulation constraints; it is released at the earliest time at which
			this is possible without violating the constraint. One key feature
			of per-flow or interleaved regulator is that, it does not increase
			worst-case latency bounds [le_boudec_theory_2018]. Specifically,
			when an interleaved regulator is appended to a FIFO subsystem, it
			does not increase the worst-case delay of the latter.
			Figure 2 shows an example of a network with 5 nodes, per-class
			queuing mechanism and interleaved regulators as in Figure 1. An end-
			to-end delay bound for flow f, traversing nodes 1 to 5, is calculated
			as follows:
	end_to_end_latency_bound_of_flow_f = C12 + C23 + C34 + S4		end_to_end_latency_bound_of_flow_f = C12 + C23 + C34 + S4
	In the above formula, Cij is a bound on the aggregate response time		In the above formula, Cij is a bound on the aggregate response time
	of the AVB FIFO queue with CBS (Credit Based Shaper) in node i and		of queuing subsystem in node i and interleaved regulator of node j,
	interleaved regulator of node j, and S4 is a bound on the response		and S4 is a bound on the response time of the queuing subsystem in
	time of the AVB FIFO queue with CBS in node 4 for flow f. In fact,		node 4 for flow f. In fact, using the delay definitions in
	using the delay definitions in Section 4.3, Cij is a bound on sum of		Section 4.2, Cij is a bound on sum of the delays 1,2,3,6 of node i
	the delays 1,2,3,6 of node i and 4,5 of node j. Similarly, S4 is a		and 4,5 of node j. Similarly, S4 is a bound on sum of the delays
	bound on sum of the delays 1,2,3,6 of node 4. The detail of		1,2,3,6 of node 4. A practical example of queuing model and delay
	calculation for the these response time bounds can be found in		calculation is presented Section 7.4.
	[TSNwithATS].
	f		f
	----------------------------->		----------------------------->
	+---+ +---+ +---+ +---+ +---+		+---+ +---+ +---+ +---+ +---+
	| 1 |---| 2 |---| 3 |---| 4 |---| 5 |		| 1 |---| 2 |---| 3 |---| 4 |---| 5 |
	+---+ +---+ +---+ +---+ +---+		+---+ +---+ +---+ +---+ +---+
	\__C12_/\__C23_/\__C34_/\_S4_/		\__C12_/\__C23_/\__C34_/\_S4_/
	Figure 2: End-to-end latency computation example		Figure 2: End-to-end latency computation example
	REMARK: The end-to-end delay bound calculation provided here gives a		REMARK: The end-to-end delay bound calculation provided here gives a
	much better upper bound in comparison with end-to-end delay bound		much better upper bound in comparison with end-to-end delay bound
	computation by adding the delay bounds of each node in the path of a		computation by adding the delay bounds of each node in the path of a
	flow [TSNwithATS].		flow [TSNwithATS].
	6. Achieving zero congestion loss		6. Achieving zero congestion loss
	When the input rate to an output queue exceeds the output rate for a		When the input rate to an output queue exceeds the output rate for a
	sufficient length of time, the queue must overflow. This is		sufficient length of time, the queue must overflow. This is
	congestion loss, and this is what deterministic networking seeks to		congestion loss, and this is what deterministic networking seeks to
	avoid.		avoid.
	6.1. A General Formula		6.1. A General Formula
	To avoid congestion losses, an upper bound on the backlog present in		To avoid congestion losses, an upper bound on the backlog present in
	the queue of Figure 1 must be computed during path computation. This		the regulator and queuing subsystem of Figure 1 must be computed
	bound depends on the set of flows that use this queue, the details of		during resource reservation. This bound depends on the set of flows
	the specific queuing mechanism and an upper bound on the processing		that use these queues, the details of the specific queuing mechanism
	delay (4). The queue must contain the packet in transmission plus		and an upper bound on the processing delay (4). The queue must
	all other packets that are waiting to be selected for output.		contain the packet in transmission plus all other packets that are
			waiting to be selected for output.
	A conservative backlog bound, that applies to all systems, can be		A conservative backlog bound, that applies to all systems, can be
	derived as follows.		derived as follows.
	The backlog bound is counted in data units (bytes, or words of		The backlog bound is counted in data units (bytes, or words of
	multiple bytes) that are relevant for buffer allocation. For every		multiple bytes) that are relevant for buffer allocation. For every
	class we need one buffer space for the packet in transmission, plus		class we need one buffer space for the packet in transmission, plus
	space for the packets that are waiting to be selected for output.		space for the packets that are waiting to be selected for output.
	Excluding transmission and preemption times, the packets are waiting		Excluding transmission and preemption times, the packets are waiting
	in the queue since reception of the last bit, for a duration equal to		in the queue since reception of the last bit, for a duration equal to
	skipping to change at page 10, line 17 ¶		skipping to change at page 11, line 13 ¶
	any class at this ouput port.		any class at this ouput port.
	Then a bound on the backlog of traffic of all classes in the queue at		Then a bound on the backlog of traffic of all classes in the queue at
	this output port is		this output port is
	backlog_bound = ( nb_classes + nb_input_ports ) *		backlog_bound = ( nb_classes + nb_input_ports ) *
	max_packet_length + total_in_rate* max_delay45		max_packet_length + total_in_rate* max_delay45
	7. Queuing model		7. Queuing model
	[[ JYLB: THIS IS WHERE DETAILS OF END-TO-END LATENCY COMPUTATION ARE
	GIVEN FOR PER-FLOW QUEUING AND FOR TSN WITH ATS]]
	7.1. Queuing data model		7.1. Queuing data model
	Sophisticated QoS mechanisms are available in Layer 3 (L3), see,		Sophisticated queuing mechanisms are available in Layer 3 (L3, see,
	e.g., [RFC7806] for an overview. In general, we assume that "Layer		e.g., [RFC7806] for an overview). In general, we assume that "Layer
	3" queues, shapers, meters, etc., are instantiated hierarchically		3" queues, shapers, meters, etc., are precisely the "regulators"
	above the "Layer 2" queuing mechanisms, among which packets compete		shown in Figure 1. The "queuing subsystems" in this figure are not
	for opportunities to be transmitted on a physical (or sometimes,		the province solely of bridges; they are an essential part of any
	logical) medium. These "Layer 2 queuing mechanisms" are not the		DetNet relay node. As illustrated by numerous implementation
	province solely of bridges; they are an essential part of any DetNet		examples, some of the "Layer 3" mechanisms described in documents
	relay node. As illustrated by numerous implementation examples, the		such as [RFC7806] are often integrated, in an implementation, with
	"Layer 3" some of mechanisms described in documents such as [RFC7806]		the "Layer 2" mechanisms also implemented in the same system. An
	are often integrated, in an implementation, with the "Layer 2"		integrated model is needed in order to successfully predict the
	mechanisms also implemented in the same system. An integrated model		interactions among the different queuing mechanisms needed in a
	is needed in order to successfully predict the interactions among the		network carrying both DetNet flows and non-DetNet flows.
	different queuing mechanisms needed in a network carrying both DetNet
	flows and non-DetNet flows.
	Figure 3 shows the (very simple) model for the flow of packets		Figure 3 shows the general model for the flow of packets through the
	through the queues of an IEEE 802.1Q bridge. Packets are assigned to		queues of a DetNet relay node. Packets are assigned to a class of
	a class of service. The classes of service are mapped to some number		service. The classes of service are mapped to some number of
	of physical FIFO queues. IEEE 802.1Q allows a maximum of 8 classes		regulator queues. Only DetNet/TSN packets pass through regulators.
	of service, but it is more common to implement 2 or 4 queues on most		Queues compete for the selection of packets to be passed to queues in
	ports.		the queuing subsystem. Packets again are selected for output from
			the queuing subsystem.
	|		|
	+--------------V---------------+		+--------------------------------V----------------------------------+
	| Class of Service Assignment |		| Class of Service Assignment |
	+--+-------+---------------+---+		+--+------+----------+---------+-----------+-----+-------+-------+--+
	| | |		| | | | | | | |
	+--V--+ +--V--+ +--V--+		+--V-+ +--V-+ +--V--+ +--V--+ +--V--+ | | |
	|Class| |Class| |Class|		|Flow| |Flow| |Flow | |Flow | |Flow | | | |
	| 0 | | 1 | . . . | n |		| 0 | | 1 | ... | i | | i+1 | ... | n | | | |
	|queue| |queue| |queue|		| reg| | reg| | reg | | reg | | reg | | | |
	+--+--+ +--+--+ +--+--+		+--+-+ +--+-+ +--+--+ +--+--+ +--+--+ | | |
	| | |		| | | | | | | |
	+--V-------V---------------V--+		+--V------V----------V--+ +--V-----------V--+ | | |
	| Transmission selection |		| Trans. selection | | Trans. select. | | | |
	+--------------+--------------+		+----------+------------+ +-----+-----------+ | | |
	|		| | | | |
	V		+--V--+ +--V--+ +--V--+ +--V--+ +--V--+
			| out | | out | | out | | out | | out |
			|queue| |queue| |queue| |queue| |queue|
			| 1 | | 2 | | 3 | | 4 | | 5 |
			+--+--+ +--+--+ +--+--+ +--+--+ +--+--+
			| | | | |
			+----------V----------------------V--------------V-------V-------V--+
			| Transmission selection |
			+----------+----------------------+--------------+-------+-------+--+
			| | | | |
			V V V V V
			DetNet/TSN queue DetNet/TSN queue non-DetNet/TSN queues
	Figure 3: IEEE 802.1Q Queuing Model: Data flow		Figure 3: IEEE 802.1Q Queuing Model: Data flow
	Some relevant mechanisms are hidden in this figure, and are performed		Some relevant mechanisms are hidden in this figure, and are performed
	in the "Class n queue" box:		in the queue boxes:
	o Discarding packets because a queue is full.		o Discarding packets because a queue is full.
	o Discarding packets marked "yellow" by a metering function, in		o Discarding packets marked "yellow" by a metering function, in
	preference to discarding "green" packets.		preference to discarding "green" packets.
	The Class of Service Assignment function can be quite complex, since		Ideally, neither of these actions are performed on DetNet packets.
	the introduction of [IEEE802.1Qci]. In addition to the Layer 2		Full queues for DetNet packets should occur only when a flow is
	priority expressed in the 802.1Q VLAN tag, a bridge can utilize any		misbehaving, and the DetNet QoS does not include "yellow" service for
	of the following information to assign a packet to a particular class		packets in excess of committed rate.
	of service (queue):
			The Class of Service Assignment function can be quite complex, even
			in a bridge [IEEE8021Q], since the introduction of [IEEE802.1Qci].
			In addition to the Layer 2 priority expressed in the 802.1Q VLAN tag,
			a DetNet relay node can utilize any of the following information to
			assign a packet to a particular class of service (queue):
	o Input port.		o Input port.
	o Selector based on a rotating schedule that starts at regular,		o Selector based on a rotating schedule that starts at regular,
	time-synchronized intervals and has nanosecond precision.		time-synchronized intervals and has nanosecond precision.
	o MAC addresses, VLAN ID, IP addresses, Layer 4 port numbers, DSCP.		o MAC addresses, VLAN ID, IP addresses, Layer 4 port numbers, DSCP.
	(Work items expected to add MPC and other indicators.)		([I-D.ietf-detnet-dp-sol-ip], [I-D.ietf-detnet-dp-sol-mpls]) (Work
			items are expected to add MPC and other indicators.)
	o The Class of Service Assignment function can contain metering and		o The Class of Service Assignment function can contain metering and
	policing functions.		policing functions.
			o MPLS and/or pseudowire ([RFC6658]) labels.
	The "Transmission selection" function decides which queue is to		The "Transmission selection" function decides which queue is to
	transfer its oldest packet to the output port when a transmission		transfer its oldest packet to the output port when a transmission
	opportunity arises.		opportunity arises.
	7.2. IEEE 802.1 Queuing Model		7.2. Preemption
	7.2.1. Queuing Data Model with Preemption
	Figure 3 must be modified if the output port supports preemption
	([IEEE8021Qbu] and [IEEE8023br]). This modification is shown in
	Figure 4.
	|
	+------------------------------V------------------------------+
	| Class of Service Assignment |
	+--+-------+-------+-------+-------+-------+-------+-------+--+
	| | | | | | | |
	+--V--+ +--V--+ +--V--+ +--V--+ +--V--+ +--V--+ +--V--+ +--V--+
	|Class| |Class| |Class| |Class| |Class| |Class| |Class| |Class|
	| a | | b | | c | | d | | e | | f | | g | | h |
	|queue| |queue| |queue| |queue| |queue| |queue| |queue| |queue|
	+--+--+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+
	| | | +-+ | | | |
	| | | | | | | |
	+--V-------V-------V------+ +V-----V-------V-------V-------V--+
	| Interrupted xmit select | | Preempting xmit select | 802.1
	+-------------+-----------+ +----------------+----------------+
	| | ======
	+-------------V-----------+ +----------------V----------------+
	| Preemptible MAC | | Express MAC | 802.3
	+--------+----------------+ +----------------+----------------+
	| |
	+--------V-----------------------------------V----------------+
	| MAC merge sublayer |
	+--------------------------+----------------------------------+
	|
	+--------------------------V----------------------------------+
	| PHY (unaware of preemption) |
	+--------------------------+----------------------------------+
	|
	V
	Figure 4: IEEE 802.1Q Queuing Model: Data flow with preemption
	From Figure 4, we can see that, in the IEEE 802 model, the preemption
	feature is modeled as consisting of two MAC/PHY stacks, one for
	packets that can be interrupted, and one for packets that can
	interrupt the interruptible packets. The Class of Service (queue)
	determines which packets are which. In Figure 4, the classes of
	service are marked "a, b, ..." instead of with numbers, in order to
	avoid any implication about which numeric Layer 2 priority values
	correspond to preemptible or preempting queues. Although it shows
	three queues going to the preemptible MAC/PHY, any assignment is
	possible.
	7.2.2. Transmission Selection Model
	In Figure 5, we expand the "Transmission selection" function of
	Figure 4.
	Figure 5 does NOT show the data path. It shows an example of a
	configuration of the IEEE 802.1Q transmission selection box shown in
	Figure 3 and Figure 4. Each queue m presents a "Class m Ready"
	signal. These signals go through various logic, filters, and state
	machines, until a single queue's "not empty" signal is chosen for
	presentation to the underlying MAC/PHY. When the MAC/PHY is ready to
	take another output packet, then a packet is selected from the one
	queue (if any) whose signal manages to pass all the way through the
	transmission selection function.
	+-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+
	|Class| |Class| |Class| |Class| |Class| |Class| |Class| |Class|
	| 1 | | 0 | | 4 | | 5 | | 6 | | 7 | | 2 | | 3 |
	|Ready| |Ready| |Ready| |Ready| |Ready| |Ready| |Ready| |Ready|
	+--+--+ +--+--+ +--+--+ +-XXX-+ +--+--+ +--+--+ +--+--+ +--+--+
	| | | | | | |
	| +--V--+ +--V--+ +--+--+ +--V--+ | +--V--+ +--V--+
	| |Prio.| |Prio.| |Prio.| |Prio.| | |Sha- | |Sha- |
	| | 0 | | 4 | | 5 | | 6 | | | per| | per|
	| | PFC | | PFC | | PFC | | PFC | | | A | | B |
	| +--+--+ +--+--+ +-XXX-+ +-XXX-+ | +--+--+ +-XXX-+
	| | | | |
	+--V--+ +--V--+ +--V--+ +--+--+ +--+--+ +--V--+ +--V--+ +--+--+
	|Time | |Time | |Time | |Time | |Time | |Time | |Time | |Time |
	| Gate| | Gate| | Gate| | Gate| | Gate| | Gate| | Gate| | Gate|
	| 1 | | 0 | | 4 | | 5 | | 6 | | 7 | | 2 | | 3 |
	+--+--+ +-XXX-+ +--+--+ +--+--+ +-XXX-+ +--+--+ +-XXX-+ +--+--+
	| | |
	+--V-------+-------V-------+--+ |
	|802.1Q Enhanced Transmission | |
	| Selection (ETS) = Weighted | |
	| Fair Queuing (WFQ) | |
	+--+-------+------XXX------+--+ |
	| |
	+--V-------+-------+-------+-------+-------V-------+-------+--+
	| Strict Priority selection (rightmost first) |
	+-XXX------+-------+-------+-------+-------+-------+-------+--+
	|
	V
	Figure 5: 802.1Q Transmission Selection
	The following explanatory notes apply to Figure 5
	o The numbers in the "Class n Ready" boxes are the values of the
	Layer 2 priority that are assigned to that Class of Service in
	this example. The rightmost CoS is the most important, the
	leftmost the least. Classes 2 and 3 are made the most important,
	because they carry DetNet flows. It is all right to make them
	more important than the priority 7 queue, which typically carries
	critical network control protocols such as spanning tree or IS-IS,
	because the shaper ensures that the highest priority best-effort
	queue (7) will get reasonable access to the MAC/PHY. Note that
	Class 5 has no Ready signal, indicating that that queue is empty.
	o Below the Class Ready signals are shown the Priority Flow Control
	gates (IEEE Std 802.1Qbb-2011 Priority-based Flow Control, now
	[IEEE8021Q] clause 36) on Classes of Service 1, 0, 4, and 5, and
	two 802.1Q shapers, A and B. Perhaps shaper A conforms to the
	IEEE Std 802.1Qav-2009 (now [IEEE8021Q] clause 34) credit-based
	shaper, and shaper B conforms to [IEEE8021Qcr] Asynchronous
	Traffic Shaper. Any given Class of Service can have either a PFC
	function or a shaper, but not both.
	o Next are the IEEE Std 802.1Qbv time gates ([IEEE8021Qbv]). Each
	one of the 8 Classes of Service has a time gate. The gates are
	controlled by a repeating schedule that restarts periodically, and
	can be programmed to turn any combination of gates on or off with
	nanosecond precision. (Although the implementation is not
	necessarily that accurate.)
	o Following the time gates, any number of Classes of Service can be
	linked to one ore more instances of the Enhanced Transmission
	Selection function. This does weighted fair queuing among the
	members of its group.
	o A final selection of the one queue to be selected for output is		In IEEE Std 802.1Q, preemption is modeled as consisting of two MAC/
	made by strict priority. Note that the priority is determined not		PHY stacks, one for packets that can be interrupted, and one for
	by the Layer 2 priority, but by the Class of Service.		packets that can interrupt the interruptible packets. The Class of
			Service (queue) determines which packets are which. Only one layer
			of preemption is supported. DetNet flows pass through the
			interrupting MAC. Only best-effort queues pass through the
			interruptible MAC, and can thus be preempted.
	o An "XXX" in the lower margin of a box (e.g. "Prio. 5 PFC"		7.3. Time-scheduled queuing
	indicates that the box has blocked the "Class n Ready" signal.
	o IEEE 802.1Qch Cyclic Queuing and Forwarding [IEEE802.1Qch] is		In [IEEE8021Qbv], the notion of time-scheduling queue gates were
	accomplished using two or three queues (e.g. 2 and 3 in the		introduced. On below every output queue (the lower row of queues in
	figure), using sophisticated time-based schedules in the Class of		Figure 3) is a gate that permits or denies the queue to present data
	Service Assignment function, and using the IEEE 802.1Qbv time		for transmission selection. The gates are controlled by a rotating
	gates [IEEE8021Qbv] to swap between the output buffers.		schedule that can be locked to a clock that is synchronized with
			other relay nodes. The DetNet class of service can be supplied by
			queuing mechanisms based on time, rather than the regulator model in
			Figure 3. These queuing mechanisms are discussed in Section 8,
			below.
	7.3. Time-Sensitive Networking with Asynchronous Traffic Shaping		7.4. Time-Sensitive Networking with Asynchronous Traffic Shaping
	Consider a network with a set of nodes (switches and hosts) along		Consider a network with a set of nodes (switches and hosts) along
	with a set of flows between hosts. Hosts are sources or destinations		with a set of flows between hosts. Hosts are sources or destinations
	of flows. There are four types of flows, namely, control-data		of flows. There are four types of flows, namely, control-data
	traffic (CDT), class A, class B, and best effort (BE) in decreasing		traffic (CDT), class A, class B, and best effort (BE) in decreasing
	order of priority. Flows of classes A and B are together referred to		order of priority. Flows of classes A and B are together referred to
	as AVB flows. It is assumed a subset of TSN functions as described		as AVB flows. It is assumed a subset of TSN functions as described
	next.		next.
	It is also assumed that contention occurs only at the output port of		It is also assumed that contention occurs only at the output port of
	a TSN node. Each node output port performs per-class scheduling with		a TSN node. Each node output port performs per-class scheduling with
	eight classes: one for CDT, one for class A traffic, one for class B		eight classes: one for CDT, one for class A traffic, one for class B
	traffic, and five for BE traffic denoted as BE0-BE4 (according to TSN		traffic, and five for BE traffic denoted as BE0-BE4 (according to TSN
	standard). In addition, each node output port also performs per-flow		standard). In addition, each node output port also performs per-flow
	regulation for AVB flows using an interleaved regulator (IR), called		regulation for AVB flows using an interleaved regulator (IR), called
	Asynchronous Traffic Shaper (ATS) in TSN. Thus, at each output port		Asynchronous Traffic Shaper (ATS) in TSN. Thus, at each output port
	of a node, there is one interleaved regulator per-input port and per-		of a node, there is one interleaved regulator per-input port and per-
	class. The detailed picture of scheduling and regulation		class. The detailed picture of scheduling and regulation
	architecture at a node output port is given by Figure 6. The packets		architecture at a node output port is given by Figure 4. The packets
	received at a node input port for a given class are enqueued in the		received at a node input port for a given class are enqueued in the
	respective interleaved regulator at the output port. Then, the		respective interleaved regulator at the output port. Then, the
	packets from all the flows, including CDT and BE flows, are enqueued		packets from all the flows, including CDT and BE flows, are enqueued
	in a class based FIFO system (CBFS) [TSNwithATS].		in a class based FIFO system (CBFS) [TSNwithATS].
	+--+ +--+ +--+ +--+		+--+ +--+ +--+ +--+
	| | | | | | | |		| | | | | | | |
	|IR| |IR| |IR| |IR|		|IR| |IR| |IR| |IR|
	| | | | | | | |		| | | | | | | |
	+-++XXX++-+ +-++XXX++-+		+-++XXX++-+ +-++XXX++-+
	| | | |		| | | |
	| | | |		| | | |
	+-----+ +-v-XXX-v-+ +-v-XXX-v-+ +-----+ +-----+ +-----+ +-----+ +-----+		+---+ +-v-XXX-v-+ +-v-XXX-v-+ +-----+ +-----+ +-----+ +-----+ +-----+
	| | | | | | |Class| |Class| |Class| |Class| |Class|		| | | | | | |Class| |Class| |Class| |Class| |Class|
	| CDT | | Class A | | Class B | | BE4 | | BE3 | | BE2 | | BE1 | | BE0 |		|CDT| | Class A | | Class B | | BE4 | | BE3 | | BE2 | | BE1 | | BE0 |
	| | | | | | | | | | | | | | | |		| | | | | | | | | | | | | | | |
	+--+--+ +----+----+ +----+----+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+		+-+-+ +----+----+ +----+----+ +--+--+ +--+--+ +--+--+ +--+--+ +--+--+
	| | | | | | | |		| | | | | | | |
	| +-v-+ +-v-+ | | | | |		| +-v-+ +-v-+ | | | | |
	| |CBS| |CBS| | | | | |		| |CBS| |CBS| | | | | |
	| +-+-+ +-+-+ | | | | |		| +-+-+ +-+-+ | | | | |
	| | | | | | | |		| | | | | | | |
	+--v---------v-----------v---------v-------V-------v-------v-------v--+		+-v--------v-----------v---------v-------V-------v-------v-------v--+
	| Strict Priority selection |		| Strict Priority selection |
	+----------------------------------+----------------------------------+		+--------------------------------+----------------------------------+
	|		|
	V		V
	Figure 6: Architecture of one TSN node output port with interleaved		Figure 4: Architecture of a TSN node output port with interleaved
	regulators (IRs)		regulators (IRs)
	The CBFS includes two CBS subsystems, one for each class A and B.		The CBFS includes two CBS subsystems, one for each class A and B.
	The CBS serves a packet from a class according to the available		The CBS serves a packet from a class according to the available
	credit for that class. The credit for each class A or B increases		credit for that class. The credit for each class A or B increases
	based on the idle slope, and decreases based on the send slope, both		based on the idle slope, and decreases based on the send slope, both
	of which are parameters of the CBS. The CDT and BE0-BE4 flows in the		of which are parameters of the CBS. The CDT and BE0-BE4 flows in the
	CBFS are served by separate FIFO subsystems. Then, packets from all		CBFS are served by separate FIFO subsystems. Then, packets from all
	flows are served by a transmission selection subsystem that serves		flows are served by a transmission selection subsystem that serves
	packets from each class based on its priority. All subsystems are		packets from each class based on its priority. All subsystems are
	non-preemptive. Guarantees for AVB traffic can be provided only if		non-preemptive. Guarantees for AVB traffic can be provided only if
	CDT traffic is bounded; it is assumed that the CDT traffic has an		CDT traffic is bounded; it is assumed that the CDT traffic has an
	affine arrival curve r t + b in each node, i.e. the amount of bits		affine arrival curve r t + b in each node, i.e. the amount of bits
	entering a node within a time interval t is bounded by r t + b.		entering a node within a time interval t is bounded by r t + b.
	[[ EM: THE FOLLOWING PARAGRAPH SHOULD BE ALIGNED WITH Section 8.2. ]]		[[ EM: THE FOLLOWING PARAGRAPH SHOULD BE ALIGNED WITH Section 9.2. ]]
	Additionally, it is assumed that flows are regulated at their source,		Additionally, it is assumed that flows are regulated at their source,
	according to either leaky bucket (LB) or length rate quotient (LRQ).		according to either leaky bucket (LB) or length rate quotient (LRQ).
	The LB-type regulation forces flow f to conform to an arrival curve		The LB-type regulation forces flow f to conform to an arrival curve
	r_f t+b_f . The LRQ-type regulation with rate r_f ensures that the		r_f t+b_f . The LRQ-type regulation with rate r_f ensures that the
	time separation between two consecutive packets of sizes l_n and		time separation between two consecutive packets of sizes l_n and
	l_n+1 is at least l_n/r_f. Note that if flow f is LRQ-regulated, it		l_n+1 is at least l_n/r_f. Note that if flow f is LRQ-regulated, it
	satisfies an arrival curve constraint r_f t + L_f where L_f is its		satisfies an arrival curve constraint r_f t + L_f where L_f is its
	maximum packet size (but the converse may not hold). For an LRQ		maximum packet size (but the converse may not hold). For an LRQ
	regulated flow, b_f = L_f. At the source hosts, the traffic		regulated flow, b_f = L_f. At the source hosts, the traffic
	satisfies its regulation constraint, i.e. the delay due to		satisfies its regulation constraint, i.e. the delay due to
	interleaved regulator at hosts is ignored.		interleaved regulator at hosts is ignored.
	At each switch implementing an interleaved regulator, packets of		At each switch implementing an interleaved regulator, packets of
	multiple flows are processed in one FIFO queue; the packet at the		multiple flows are processed in one FIFO queue; the packet at the
	head of the queue is regulated based on its regulation constraints;		head of the queue is regulated based on its regulation constraints;
	it is released at the earliest time at which this is possible without		it is released at the earliest time at which this is possible without
	violating the constraint. The regulation type and parameters for a		violating the constraint. The regulation type and parameters for a
	flow are the same at its source and at all switches along its path.		flow are the same at its source and at all switches along its path.
	7.4. Other queuing models, e.g. IntServ		Details of end-to-end delay bound calculation in such a system is
			described in [TSNwithATS].
	[[NWF More sections that discuss specific models]]		7.5. IntServ
	8. Parameters for the bounded latency model		In this section, a worst-case queuing latency calculating method is
			provided. In deterministic network, the traffic of a flow is
			constrained by arrival curve. Queuing mechanisms in a DetNet node
			can be characterized and constrained by service curve. By using
			arrival curve and service curve with Network Calculus theory
			[NetCalBook], a tight worst-case queuing latency can be calculated.
	8.1. Sender parameters		Considering a DetNet flow at output port, R(s) is the cumulative
			arrival data until time s. For any time period t, the incremental
			arrival data is constrained by an arrival curve a(t)
	8.2. Relay system parameters		R(s+t)-R(s) <= a(t), \any s>=0, t>=0
	[[NWF This section talks about the paramters that must be passed hop-		The scheduling that a relay node performs to a DetNet flow can be
	by-hop (T-SPEC? F-SPEC?) by a resoure reservation protocol.]]		abstracted as service curve. It describes the minimal service the
			network can offer. The service curve b(t) of a node is defined as
			below, if the accumulative input data R and output data R_out of the
			node satisfies
	9. References		R_out(t) >= inf(R(s) + b(t-s) ), \any s <=t
	9.1. Normative References		where the operator "inf" calculates the greatest lower bound in
			period t.
			By calculating the maximum vertical deviation between arrival curve
			a(t) and service curve b(t), one can obtain the backlog bound in data
			unit
			Backlog_bound = sup_t(a(t) - b(t) )
			where operator "sup_t" calculates the minimum upper bound with
			respect to t. The buffer space at a node should be no less than the
			backlog bound to achieve zero congestion loss.
			NOTE: Section 6.1 gives a general formula for computing the buffer
			requirements. This is an alternative calculation based on the
			arrival curve and service curve.
			By calculating the maximum horizontal deviation between arrival curve
			a(t) and service curve b(t), one can obtain the delay bound as below
			Delay_bound = sup_s( inf_t( t>=0 | a(s) <= b(s+t) )
			where the operator " inf_t" calculates the maximum lower bound with
			respect to t, the operator "sup_s" calculates the minimum upper bound
			with respect to s. Figure 5 shows an example of arival curve,
			service curve, backlog bound h, and delay bound v.
			+ bit . *
			| . *
			| . *
			| *
			| * .
			| * .
			| * | . .. Service curve
			*-----h-|---. ** Arrival curve
			| v . h Delay_bound
			| | . v Backlog_bound
			| |.
			+-------.--------------------+ time
			Figure 5: Computation of backlog bound and delay bound. Note that
			arrival and service curves are not necessary to be linear.
			Note that in the formula of Delay_bound, the service curve b(t) can
			describe either per-hop scheduling that a DetNet node offers to a
			flow, or concatenation of multiple nodes that represents end-to-end
			scheduling that DetNet path offers to a flow. In the latter case,
			the obtained delay bound is end-to-end worst case delay. To
			calculate this, we should at first derive the concatenated service
			curve.
			Consider a flow traverse two DetNet nodes, which offer service curve
			b1(t) and b2(t) sequentially. Then concatenation of the two nodes
			offers a service curve b_concatenated as below
			b_concatenated(t) =inf_s (b1(s) + b2(t-s) ) , \any 0 <=s <=t
			The concatenation of service curve can be directly generalized to
			include more than two nodes.
			a_out(t) = sup_u( a(t+u) - b(u) ), \any u>=0
			In DetNet, the arrival curve and service curve can be characterized
			by a group of parameters, which will be defined in Section 8.
			Integrated service (IntServ) is an architecture that specifies the
			elements to guarantee quality of service (QoS) on networks. To
			satisfied guaranteed service, a flow must conform to a traffic
			specification (T-spec), and reservation is made along a path, only if
			routers are able to guarantee the required bandwidth and buffer.
			Consider the traffic model which conforms to token bucket regulator
			(r, b), with
			o Token bucket depth (b).
			o Token bucket rate (r).
			The traffic specification can be described as an arrival curve a(t)
			alpha(t) = b + rt
			This token bucket regulator requires that, during any time window of
			width t, the number of bit for the flow is limited by alpha(t) = b +
			rt.
			If resource reservation on a path is applied, IntServ model on a
			router can be described as a rate-latency service curve beta(t).
			beta(t) = max(0, R(t-T))
			It describes that bits might have to wait up to T before being served
			with a rate greater or equal to R.
			It should be noted that, the guaranteed service rate R is a share of
			link's bandwidth. The choice of R is related to the specification of
			flows which will transmit on this node. For example, in strict
			priority policy, considering a flow with priority j, its share of
			bandwidth may be R=c-sum(r_i), i<j, where c is the link bandwidth,
			r_i is the token bucket rate for the flows with priority higher than
			j. The choice of T is also related to the specification of all the
			flows traversing this node. For example, in a generalized processor
			sharing (GPS) node, T = L / R + L_max/c, where L is the maximum
			packet size for the flow, L_max is the maximum packet size in the
			node across all flows. Other choice of R and T are also supported,
			according to the specific scheduling of the node and flows traversing
			this node.
			As mentioned previously in this section, delay bound and backlog
			bound can be easily obtained by comparing arrival curve and service
			curve. Backlog bound, or buffer bound, is the maximum vertical
			derivation between curves alpha(t) and beta(t), which is x=b+rT.
			Delay bound is the maximum horizontal derivation between curves
			alpha(t) and beta(t), which is d = T+b/R. Graphical illustration of
			the IntServ model is shown in Figure 5.
			The output bound, or the next-hop arrival curve, is alpha_out(t) = b
			+ rT + rt, where burstiness of the flow is increased by rT, compared
			with the arrival curve.
			We can calculate the end-to-end delay bound, for a path including N
			nodes, among which the i-th node offers service curve beta_i(t),
			beta_i(t) = max(0, R_i(t-T_i)), i=1,...,N
			According to [Section 5.1], by concatenating those IntServ nodes, an
			end-to-end service curve can be computed as
			beta_e2e (t) = max(0, R_e2e(t-T_e2e) )
			where
			R_e2e = min(R_1,..., R_N)
			T_e2e = T_1 + ... + T_N
			Similarly, delay bound, backlog bound and output bound can be
			computed by using the original arrival curve alpha(t) and
			concatenated service curve beta_e2e(t).
			8. Time-based DetNet QoS
			8.1. Cyclic Queuing and Forwarding
			[IEEE802.1Qci] and [IEEE802.1Qch] describe Cyclic Queuing and
			Forwarding (CQF), which provide the bounded latency and zero
			congestion loss using the time-scheduled gates of [IEEE8021Qbv]. For
			each different DetNet class of service, a set of two or three buffers
			is provided at the out queue layer of Figure 3. A cycle time is
			configured for each class, and all of the buffer sets in a class swap
			buffers simultaneously throughout the DetNet domain at that cycle
			rate. The choice of using two or three buffers depends on the link
			lengths and forwarding delay times; two buffers can be used if the
			delay from hop to hop is nearly an integral number of cycle times,
			and three are required if not. Flows are assigned to a class of
			service only until the amount of data to be transmitted in one cycle
			would exceed the cycle time for some interface. Every packet dwells
			either two or three cycles at each hop, so the calculation of worst-
			case latency and latency variation is trivial.
			8.2. Time Scheduled Queuing
			[IEEE8021Qbv] specifies a time-aware queue-draining procedure for
			transmission selection at egress port of a relay node, which supports
			up to eight traffic classes. Each traffic class has a separate
			queue, frame transmission from each queue is allowed or prevented by
			a time gate. This time gate controlled scheduling allows time-
			sensitive traffic classes to transmit on dedicate time slots. Within
			the time slots, the transmitting flows can be granted exclusive use
			of the transmission medium. Generally, this time-aware scheduling is
			a layer 2 time division multiplexing (TDM) technique.
			Consider the static configuration of a deterministic network. To
			provide end-to-end latency guaranteed service, network nodes can
			support time-based behavior, which is determined by gate control list
			(GCL). GCL defines the gate operation, in open or closed state, with
			associated timing for each traffic class queue. A time slice with
			gate state "open" is called transmission window. The time-based
			traffic scheduling must be coordinated among the relay nodes along
			the path from sender to receiver, to control the transmission of
			time-sensitive traffic.
			Ideally all network devices are time synchronized and static GCL
			configurations on all devices along the routed path are coordinated
			to ensure that length of transmission window fits the assigned
			frames, and no two time windows for DetNet traffic on the same port
			overlap. (DetNet flows' windows can overlap with best-effort
			windows, so that unused DetNet bandwidth is available to best-effort
			traffic.) The processing delay, link delay and output delay in
			transmitting are considered in GCL computation. Transmission window
			for a certain flow may require that a time offset on consecutive hops
			be selected to reduce queueing delay as much as possible. In this
			case, TSN/DetNet frames transmit at the assigned transmission window
			at every node through the routed path, with zero congestion loss and
			bounded end-to-end latency. Then, the worst-case end-to-end latency
			of flow can be derived from GCL configuration. For a TSN or DetNet
			frame, denote the transmission window on last hop closes at
			gate_close_time_last_hop. Assuming talker supports scheduled traffic
			behavior, it starts the transmission at gate_open_time_on_talker.
			Then worst case end-to-end delay of this flow is bounded by
			gate_close_time_last_hop - gate_open_time_on_talker +
			link_delay_last_hop.
			It should be noted that scheduled traffic service relies on a
			synchronized network and coordinated GCL configuration. Synthesis of
			GCL on multiple nodes in network is a scheduling problem considering
			all TSN/DetNet flows traversing the network, which is a non-
			deterministic polynomial-time hard (NP-hard) problem. Also, at this
			writing, scheduled traffic service supports no more than eight
			traffic classes, typically using up to seven priority classes and at
			least one best effort class.
			9. Parameters for the bounded latency model
			9.1. Sender parameters
			9.2. Relay system parameters
			[[NWF This section talks about the parameters that must be used hop-
			by-hop by a resource reservation protocol.]]
			10. References
			10.1. Normative References
	[I-D.ietf-detnet-architecture]		[I-D.ietf-detnet-architecture]
	Finn, N. and P. Thubert, "Deterministic Networking		Finn, N., Thubert, P., Varga, B., and J. Farkas,
	Architecture", draft-ietf-detnet-architecture-00 (work in		"Deterministic Networking Architecture", draft-ietf-
	progress), September 2016.		detnet-architecture-08 (work in progress), September 2018.
	[I-D.ietf-detnet-dp-alt]		[I-D.ietf-detnet-dp-sol-ip]
	Korhonen, J., Farkas, J., Mirsky, G., Thubert, P.,		Korhonen, J. and B. Varga, "DetNet IP Data Plane
	Zhuangyan, Z., and L. Berger, "DetNet Data Plane Protocol		Encapsulation", draft-ietf-detnet-dp-sol-ip-00 (work in
	and Solution Alternatives", draft-ietf-detnet-dp-alt-00		progress), July 2018.
	(work in progress), October 2016.
			[I-D.ietf-detnet-dp-sol-mpls]
			Korhonen, J. and B. Varga, "DetNet MPLS Data Plane
			Encapsulation", draft-ietf-detnet-dp-sol-mpls-00 (work in
			progress), July 2018.
	[I-D.ietf-detnet-use-cases]		[I-D.ietf-detnet-use-cases]
	Grossman, E., "Deterministic Networking Use Cases", draft-		Grossman, E., "Deterministic Networking Use Cases", draft-
	ietf-detnet-use-cases-16 (work in progress), May 2018.		ietf-detnet-use-cases-19 (work in progress), October 2018.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", BCP 14, RFC 2119,		Requirement Levels", BCP 14, RFC 2119,
	DOI 10.17487/RFC2119, March 1997,		DOI 10.17487/RFC2119, March 1997,
	<https://www.rfc-editor.org/info/rfc2119>.		<https://www.rfc-editor.org/info/rfc2119>.
	[RFC2212] Shenker, S., Partridge, C., and R. Guerin, "Specification		[RFC2212] Shenker, S., Partridge, C., and R. Guerin, "Specification
	of Guaranteed Quality of Service", RFC 2212,		of Guaranteed Quality of Service", RFC 2212,
	DOI 10.17487/RFC2212, September 1997,		DOI 10.17487/RFC2212, September 1997,
	<https://www.rfc-editor.org/info/rfc2212>.		<https://www.rfc-editor.org/info/rfc2212>.
	[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
	Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
	2006, <https://www.rfc-editor.org/info/rfc4364>.
	[RFC6658] Bryant, S., Ed., Martini, L., Swallow, G., and A. Malis,		[RFC6658] Bryant, S., Ed., Martini, L., Swallow, G., and A. Malis,
	"Packet Pseudowire Encapsulation over an MPLS PSN",		"Packet Pseudowire Encapsulation over an MPLS PSN",
	RFC 6658, DOI 10.17487/RFC6658, July 2012,		RFC 6658, DOI 10.17487/RFC6658, July 2012,
	<https://www.rfc-editor.org/info/rfc6658>.		<https://www.rfc-editor.org/info/rfc6658>.
	[RFC7806] Baker, F. and R. Pan, "On Queuing, Marking, and Dropping",		[RFC7806] Baker, F. and R. Pan, "On Queuing, Marking, and Dropping",
	RFC 7806, DOI 10.17487/RFC7806, April 2016,		RFC 7806, DOI 10.17487/RFC7806, April 2016,
	<https://www.rfc-editor.org/info/rfc7806>.		<https://www.rfc-editor.org/info/rfc7806>.
	9.2. Informative References		10.2. Informative References
			[bennett2002delay]
			J.C.R. Bennett, K. Benson, A. Charny, W.F. Courtney, and
			J.-Y. Le Boudec, "Delay Jitter Bounds and Packet Scale
			Rate Guarantee for Expedited Forwarding",
			<https://dl.acm.org/citation.cfm?id=581870>.
			[charny2000delay]
			A. Charny and J.-Y. Le Boudec, "Delay Bounds in a Network
			with Aggregate Scheduling", <https://link.springer.com/
			chapter/10.1007/3-540-39939-9_1>.
	[IEEE802.1Qch]		[IEEE802.1Qch]
	IEEE, "IEEE Std 802.1Qch-2017 IEEE Standard for Local and		IEEE, "IEEE Std 802.1Qch-2017 IEEE Standard for Local and
	metropolitan area networks - Bridges and Bridged Networks		metropolitan area networks - Bridges and Bridged Networks
	Amendment 29: Cyclic Queuing and Forwarding (amendment to		Amendment 29: Cyclic Queuing and Forwarding (amendment to
	802.1Q-2014)", 2017,		802.1Q-2014)", 2017,
	<http://www.ieee802.org/1/files/private/ch-drafts/>.		<http://www.ieee802.org/1/files/private/ch-drafts/>.
	[IEEE802.1Qci]		[IEEE802.1Qci]
	IEEE, "IEEE Std 802.1Qci-2017 IEEE Standard for Local and		IEEE, "IEEE Std 802.1Qci-2017 IEEE Standard for Local and
	skipping to change at page 19, line 29 ¶		skipping to change at page 23, line 15 ¶
	[IEEE8021Qcr]		[IEEE8021Qcr]
	IEEE 802.1, "IEEE P802.1Qcr: IEEE Draft Standard for Local		IEEE 802.1, "IEEE P802.1Qcr: IEEE Draft Standard for Local
	and metropolitan area networks - Bridges and Bridged		and metropolitan area networks - Bridges and Bridged
	Networks - Amendment: Asynchronous Traffic Shaping", 2017,		Networks - Amendment: Asynchronous Traffic Shaping", 2017,
	<http://www.ieee802.org/1/files/private/cr-drafts/>.		<http://www.ieee802.org/1/files/private/cr-drafts/>.
	[IEEE8021TSN]		[IEEE8021TSN]
	IEEE 802.1, "IEEE 802.1 Time-Sensitive Networking (TSN)		IEEE 802.1, "IEEE 802.1 Time-Sensitive Networking (TSN)
	Task Group", <http://www.ieee802.org/1/>.		Task Group", <http://www.ieee802.org/1/>.
	[IEEE8023]
	IEEE 802.3, "IEEE Std 802.3-2015: IEEE Standard for Local
	and metropolitan area networks - Ethernet", 2015,
	<http://standards.ieee.org/getieee802/
	download/802.3-2015.zip>.
	[IEEE8023br]		[IEEE8023br]
	IEEE 802.3, "IEEE Std 802.3br-2016: IEEE Standard for		IEEE 802.3, "IEEE Std 802.3br-2016: IEEE Standard for
	Local and metropolitan area networks - Ethernet -		Local and metropolitan area networks - Ethernet -
	Amendment 5: Specification and Management Parameters for		Amendment 5: Specification and Management Parameters for
	Interspersing Express Traffic", 2016,		Interspersing Express Traffic", 2016,
	<http://standards.ieee.org/getieee802/		<http://standards.ieee.org/getieee802/
	download/802.3br-2016.pdf>.		download/802.3br-2016.pdf>.
			[le_boudec_theory_2018]
			J.-Y. Le Boudec, "A Theory of Traffic Regulators for
			Deterministic Networks with Application to Interleaved
			Regulators", <http://arxiv.org/abs/1801.08477/>.
			[NetCalBook]
			Le Boudec, Jean-Yves, and Patrick Thiran, "Network
			calculus: a theory of deterministic queuing systems for
			the internet", 2001, <https://arxiv.org/abs/1804.10608/>.
			[Specht2016UBS]
			J. Specht and S. Samii, "Urgency-Based Scheduler for Time-
			Sensitive Switched Ethernet Networks",
			<https://ieeexplore.ieee.org/abstract/document/7557870>.
	[TSNwithATS]		[TSNwithATS]
	E. Mohammadpour, E. Stai, M. Mohiuddin, and J.-Y. Le		E. Mohammadpour, E. Stai, M. Mohiuddin, and J.-Y. Le
	Boudec, "End-to-end Latency and Backlog Bounds in Time-		Boudec, "End-to-end Latency and Backlog Bounds in Time-
	Sensitive Networking with Credit Based Shapers and		Sensitive Networking with Credit Based Shapers and
	Asynchronous Traffic Shaping",		Asynchronous Traffic Shaping",
	<https://arxiv.org/abs/1804.10608/>.		<https://arxiv.org/abs/1804.10608/>.
	Authors' Addresses		Authors' Addresses
	Norman Finn		Norman Finn
	Huawei Technologies Co. Ltd		Huawei Technologies Co. Ltd
	3101 Rio Way		3101 Rio Way
	Spring Valley, California 91977		Spring Valley, California 91977
	US		US
	Phone: +1 925 980 6430		Phone: +1 925 980 6430
	Email: norman.finn@mail01.huawei.com		Email: norman.finn@mail01.huawei.com
	Jean-Yves Le Boudec		Jean-Yves Le Boudec
	skipping to change at page 20, line 32 ¶		skipping to change at page 24, line 29 ¶
	Email: jean-yves.leboudec@epfl.ch		Email: jean-yves.leboudec@epfl.ch
	Ehsan Mohammadpour		Ehsan Mohammadpour
	EPFL		EPFL
	IC Station 14		IC Station 14
	Lausanne EPFL 1015		Lausanne EPFL 1015
	Switzerland		Switzerland
	Email: ehsan.mohammadpour@epfl.ch		Email: ehsan.mohammadpour@epfl.ch
			Jiayi Zhang
			Huawei Technologies Co. Ltd
			Q22, No.156 Beiqing Road
			Beijing 100095
			China
			Email: zhangjiayi11@huawei.com
	Balazs Varga		Balazs Varga
	Ericsson		Ericsson
	Konyves Kalman krt. 11/B		Konyves Kalman krt. 11/B
	Budapest 1097		Budapest 1097
	Hungary		Hungary
	Email: balazs.a.varga@ericsson.com		Email: balazs.a.varga@ericsson.com
	Janos Farkas		Janos Farkas
	Ericsson		Ericsson
	Konyves Kalman krt. 11/B		Konyves Kalman krt. 11/B
	Budapest 1097		Budapest 1097
	Hungary		Hungary
	Email: janos.farkas@ericsson.com		Email: janos.farkas@ericsson.com
End of changes. 83 change blocks.
	374 lines changed or deleted		568 lines changed or added
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