Network Working Group
Internet Engineering Task Force (IETF) S. Gringeri
Internet-Draft
Request for Comments: 9801 J. Whittaker
Intended status:
Category: Standards Track Verizon
Expires: 16 August 2025
ISSN: 2070-1721 N. Leymann
Deutsche Telekom
C. Schmutzer, Ed.
Cisco Systems, Inc.
C. Brown
Ciena Corporation
12 February
June 2025
Private Line Emulation over Packet Switched Networks
draft-ietf-pals-ple-15
Abstract
This document expands the applicability of virtual private wire
services Virtual Private Wire
Service (VPWS) bit-stream payloads beyond Time Division Multiplexing
(TDM) signals and provides pseudowire transport with complete signal
transparency over packet switched networks (PSN). Packet Switched Networks (PSNs).
Status of This Memo
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This Internet-Draft will expire on 16 August 2025.
https://www.rfc-editor.org/info/rfc9801.
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Table of Contents
1. Introduction and Motivation . . . . . . . . . . . . . . . . . 3
2. Requirements Notation . . . . . . . . . . . . . . . . . . . . 4
3. Terminology and Reference Model . . . . . . . . . . . . . . . 4 Models
3.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Reference Models . . . . . . . . . . . . . . . . . . . . 7
4. Emulated Services . . . . . . . . . . . . . . . . . . . . . . 9
4.1. Generic PLE Service . . . . . . . . . . . . . . . . . . . 9
4.2. Ethernet services . . . . . . . . . . . . . . . . . . . . 9 Services
4.2.1. 1000BASE-X . . . . . . . . . . . . . . . . . . . . . 10
4.2.2. 10GBASE-R and 25GBASE-R . . . . . . . . . . . . . . . 10
4.2.3. 40GBASE-R, 50GBASE-R 50GBASE-R, and 100GBASE-R . . . . . . . . . 11
4.2.4. 200GBASE-R and 400GBASE-R . . . . . . . . . . . . . . 12
4.2.5. Energy Efficient Ethernet (EEE) . . . . . . . . . . . 14
4.3. SONET/SDH Services . . . . . . . . . . . . . . . . . . . 14
4.4. Fibre Channel Services . . . . . . . . . . . . . . . . . 15
4.4.1. 1GFC, 2GFC, 4GFC 4GFC, and 8GFC . . . . . . . . . . . . . . 15
4.4.2. 16GFC . . . . . . . . . . . . . . . . . . . . . . . . 16
4.4.3. 32GFC and 4-lane 4-Lane 128GFC . . . . . . . . . . . . . . . 17
4.4.4. 64GFC . . . . . . . . . . . . . . . . . . . . . . . . 18
4.5. OTN Services . . . . . . . . . . . . . . . . . . . . . . 19
5. PLE Encapsulation Layer . . . . . . . . . . . . . . . . . . . 20
5.1. PSN and VPWS Demultiplexing Headers . . . . . . . . . . . 20
5.1.1. New SRv6 Behaviors . . . . . . . . . . . . . . . . . 21
5.2. PLE Header . . . . . . . . . . . . . . . . . . . . . . . 22
5.2.1. PLE Control Word . . . . . . . . . . . . . . . . . . 22
5.2.2. RTP Header . . . . . . . . . . . . . . . . . . . . . 23
6. PLE Payload Layer . . . . . . . . . . . . . . . . . . . . . . 25
6.1. Basic Payload . . . . . . . . . . . . . . . . . . . . . . 25
6.2. Byte aligned Byte-Aligned Payload . . . . . . . . . . . . . . . . . . 25
7. PLE Operation . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1. Common Considerations . . . . . . . . . . . . . . . . . . 26
7.2. PLE IWF Operation . . . . . . . . . . . . . . . . . . . . 26
7.2.1. PSN-bound PSN-Bound Encapsulation Behavior . . . . . . . . . . 26
7.2.2. CE-bound CE-Bound Decapsulation Behavior . . . . . . . . . . . 26
7.3. PLE Performance Monitoring . . . . . . . . . . . . . . . 28
7.4. PLE Fault Management . . . . . . . . . . . . . . . . . . 29
8. QoS and Congestion Control . . . . . . . . . . . . . . . . . 30
9. Security Considerations . . . . . . . . . . . . . . . . . . . 30
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 31
10.1. Bit-stream Bit-Stream Next Header Type . . . . . . . . . . . . . . 31
10.2. SRv6 Endpoint Behaviors . . . . . . . . . . . . . . . . 31
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 32
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 32
12.1.
11.1. Normative References . . . . . . . . . . . . . . . . . . 32
12.2.
11.2. Informative References . . . . . . . . . . . . . . . . . 35
Acknowledgements
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 40
1. Introduction and Motivation
This document describes a method called Private Line Emulation (PLE)
for encapsulating not only Time Division Multiplexing (TDM) signals
as bit-stream Virtual Private Wire Service (VPWS) over Packet
Switched Networks (PSN). In this regard, it complements methods
described in [RFC4553].
This emulation suits applications, where carrying Protocol Data Units
(PDUs) as defined in [RFC4906] or [RFC4448] is not enough, physical
layer signal transparency is required and data or framing structure
interpretation of the Provider Edge (PE) would be counterproductive.
One example of such case is two Ethernet connected Ethernet-connected Customer Edge (CE)
devices and the need for Synchronous Ethernet [G.8261] operation (see
[G.8261]) between them without the intermediate PE devices
interfering or addressing concerns about Ethernet control protocol
transparency for
PDU based PDU-based carrier Ethernet services, beyond the
behavior definitions of Metro Ethernet MEF Forum (MEF) specifications.
Another example would be a Storage Area Networking (SAN) extension
between two data centers. Operating at a bit-stream level allows for
a connection between Fibre Channel switches without interfering with
any of the Fibre Channel protocol mechanisms defined by [T11].
Also, SONET/SDH (Synchronous Optical Network (SONET) / Synchronous
Digital Hierarchy (SDH)) add/drop multiplexers or cross-connects can
be interconnected without interfering with the multiplexing
structures and networks mechanisms. This is a key distinction to
Circuit Emulation over Packet (CEP) defined in [RFC4842] where demultiplexing
and
multiplexing and demultiplexing is desired in order to operate per
SONET Synchronous Payload Envelope (SPE) and Virtual Tributary (VT)
or SDH Virtual Container (VC). Said in another way, In other words, PLE does provide provides an
independent layer network underneath the SONET/SDH layer network,
whereas CEP
does operate operates at the same level and peer with the SONET/SDH
layer network.
The mechanisms described in this document follow principles similar
to Structure-Agnostic Time Division Multiplexing (TDM) TDM over Packet (SAToP) defined (defined in [RFC4553]. [RFC4553]).
The applicability is expanded beyond the narrow set of Plesiochronous
Digital Hierarchy (PDH) interfaces (T1, E1, T3 T3, and E3) to allow the
transport of signals from many different technologies such as
Ethernet, Fibre Channel, SONET/SDH
[GR253]/[G.707] ([GR253] / [G.707]), and OTN
[G.709] at gigabit speeds. The signals are treated as bit-stream payload
payload, which was defined in the Pseudo Wire Emulation Edge-to-Edge
(PWE3) architecture in [RFC3985] sections Sections 3.3.3 and 3.3.4. 3.3.4 of [RFC3985].
2. Requirements Notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Terminology and Reference Model Models
3.1. Terminology
* ACH -
ACH: Associated Channel Header [RFC7212]
* AIS -
AIS: Alarm Indication Signal
* AIS-L -
AIS-L: Line AIS
* AS - Autonomous System
* ASBR - Autonomous System Border Router
* MS-AIS -
MS-AIS: Multiplex Section AIS
* BITS -
BITS: Building Integrated Timing Supply [ATIS-0900105.09.2013]
* CBR -
CBR: Constant Bit Rate
* CE -
CE: Customer Edge
* CEP -
CEP: Circuit Emulation over Packet [RFC4842]
* CSRC -
CSRC: Contributing SouRCe Source [RFC3550]
* DEG -
DEG: Degradation
* ES -
ES: Errored Second
* FEC -
FEC: Forward Error Correction
* ICMP -
ICMP: Internet Control Message Protocol [RFC4443]
* IEEE -
IEEE: Institute of Electrical and Electronics Engineers
* INCITS - InterNational
INCITS: INternational Committee for Information Technology Standards
* IWF - InterWorking
IWF: Interworking Function
* LDP -
LDP: Label Distribution Protocol [RFC5036], [RFC8077]
* LF -
LF: Local Fault
* LOF -
LOF: Loss Of Frame
* LOM -
LOM: Loss Of Multiframe
* LOS -
LOS: Loss Of Signal
* LPI -
LPI: Low Power Idle
* LSP -
LSP: Label Switched Path
*
MEF: MEF - Metro Ethernet Forum
* MPLS - Multi Protocol
MPLS: Multiprotocol Label Switching [RFC3031]
* NOS -
NOS: Not Operational
* NSP -
NSP: Native Service Processor Processing [RFC3985]
* ODUk -
ODUk: Optical Data Unit k
* OTN -
OTN: Optical Transport Network
* OTUk -
OTUk: Optical Transport Unit k
* PCS -
PCS: Physical Coding Sublayer
* PDH - Plesiochronous Digital Hierarchy
* PDV -
PDV: Packet Delay Variation
* PE -
PE: Provider Edge
* PLE -
PLE: Private Line Emulation
* PLOS -
PLOS: Packet Loss Of Signal
* PLR -
PLR: Packet Loss Ratio
* PMA - Rate
PMA: Physical Medium Attachment
* PMD -
PMD: Physical Medium Dependent
* PSN -
PSN: Packet Switched Network
* PTP -
PTP: Precision Time Protocol
* PW -
PW: Pseudowire [RFC3985]
* PWE3 -
PWE3: Pseudo Wire Emulation Edge-to-Edge [RFC3985]
* P2P - Point-to-Point
* QOS - Quality Of Service
* RDI -
RDI: Remote Defect Indication
* RSVP-TE -
RSVP-TE: Resource Reservation Protocol Traffic Engineering [RFC4875]
* RTCP -
RTCP: RTP Control Protocol [RFC3550]
* RTP - Realtime
RTP: Real-time Transport Protocol [RFC3550]
* SAN - Storage Area Network
* SAToP - Structure-Agnostic Time Division Multiplexing (TDM) over
Packet [RFC4553]
* SD -
SD: Signal Degrade
* SES -
SES: Severely Errored Second
* SDH - Seconds
SDH: Synchronous Digital Hierarchy
* SID -
SID: Segment Identifier [RFC8402]
* SPE - Synchronous Payload Envelope
* SR -
SR: Segment Routing [RFC8402]
* SRH -
SRH: Segment Routing Header [RFC8754]
* SRTP -
SRTP: Secure Realtime Real-time Transport Protocol [RFC3711]
* SRv6 -
SRv6: Segment Routing over IPv6 Dataplane [RFC8986]
* SSRC -
SSRC: Synchronization SouRCe Source [RFC3550]
* SONET -
SONET: Synchronous Optical Network
* TCP -
TCP: Transmission Control Protocol [RFC9293]
* TDM -
TDM: Time Division Multiplexing
* TTS -
TTS: Transmitter Training Signal
* UAS -
UAS: Unavailable Second
* VPWS - Seconds
VPWS: Virtual Private Wire Service [RFC3985]
* VC - Virtual Circuit
* VT - Virtual Tributary
Note: The term Interworking Function (IWF) is used to describe the
functional block that encapsulates bit streams into PLE packets and
in the reverse direction decapsulates PLE packets and reconstructs
bit streams.
3.2. Reference Models
The reference model for PLE is illustrated in Figure 1 and is inline
with the reference model defined in Section 4.1 of [RFC3985]. PLE
does rely
relies on PWE3 pre-processing, preprocessing, in particular the concept of a Native
Service Processing (NSP) function defined in Section 4.2.2 of
[RFC3985].
|<--- p2p L2VPN service -->|
| |
| |<-PSN tunnel->| |
v v v v
+---------+ +---------+
| PE1 |==============| PE2 |
+---+-----+ +-----+---+
+-----+ | N | | | | N | +-----+
| CE1 |-----| S | IWF |.....VPWS.....| IWF | S |-----| CE2 |
+-----+ ^ | P | | | | P | ^ +-----+
| +---+-----+ +-----+---+ |
CE1 physical ^ ^ CE2 physical
interface | | interface
|<--- emulated service --->|
| |
attachment attachment
circuit circuit
Figure 1: PLE Reference Model
PLE embraces the minimum intervention principle outlined in
Section 3.3.5 of [RFC3985] whereas the data is flowing through the
PLE encapsulation layer as received without modifications.
For some service types types, the NSP function is responsible for
performing operations on the native data received from the CE.
Examples are terminating Forward Error Correction (FEC), terminating
the OTUk layer for OTN OTN, or dealing with multi-lane processing. After
the NSP, the IWF is generating the payload of the VPWS VPWS, which is
carried via a PSN tunnel.
To allow the clock of the transported signal to be carried across the
PLE domain in a transparent way way, the relative network synchronization
reference model and deployment scenario outlined in Section 4.3.2 of
[RFC4197] are applicable and are shown in Figure 2.
J
| G
| |
| +-----+ +-----+ v
+-----+ v |- - -|=================|- - -| +-----+
| |<---------|.............................|<---------| |
| CE1 | | PE1 | VPWS | PE2 | | CE2 |
| |--------->|.............................|--------->| |
+-----+ |- - -|=================|- - -| ^ +-----+
^ +-----+ +-----+ |
| ^ C D ^ |
A | | |
+-----------+-----------+ E
|
+-+
|I|
+-+
Figure 2: Relative Network Scenario Timing
The local oscillators C of PE1 and D of PE2 are locked to a common
clock I.
The attachment circuit clock E is generated by PE2 via a differential
clock recovery method in reference to the common clock I. For this
to work work, the difference between clock A and clock C (locked to I)
MUST be explicitly transferred from PE1 to PE2 using the timestamp
inside the RTP header.
For the reverse direction direction, PE1 does generate generates the attachment circuit clock
J and the clock difference between G and D (locked to I) transferred
from PE2 to PE1.
The method used to lock clocks C and D to the common clock I is out
of scope of this document, but document; however, there are already several well-
established concepts for achieving clock synchronization, commonly synchronization (commonly
also referred to as frequency synchronization, "frequency synchronization") available.
While using external timing inputs (aka BITS [ATIS-0900105.09.2013])
or synchronous Ethernet as (as defined in [G.8261] [G.8261]), the characteristics
and limits defined in [G.8262] have to be considered.
While relying on precision time protocol (PTP) as (as defined in
[G.8265.1],
[G.8265.1]), the network limits defined in [G.8261.1] have to be
considered.
4. Emulated Services
This specification describes the emulation of services from a wide
range of technologies, such as TDM, Ethernet, Fibre Channel, or OTN,
as bit streams or structured bit streams, as defined in Section Sections
3.3.3 and Section 3.3.4 of [RFC3985].
4.1. Generic PLE Service
The generic PLE service is an example of the bit stream defined in
Section 3.3.3 of [RFC3985].
Under the assumption that the CE-bound IWF is not responsible for any
service specific
service-specific operation, a bit stream of any rate can be carried
using the generic PLE payload.
There is no NSP function present for this service.
4.2. Ethernet services Services
Ethernet services are special cases of the structured bit stream
defined in Section 3.3.4 of [RFC3985].
The IEEE has defined several layers for Ethernet in [IEEE802.3].
Emulation is operating at the physical (PHY) layer, more precisely at
the Physical Coding Sublayer (PCS).
Over time time, many different Ethernet interface types have been
specified in [IEEE802.3] with a varying set of characteristics characteristics, such
as optional
vs versus mandatory FEC and single-lane vs versus multi-lane
transmission.
Ethernet interface types with backplane physical media dependent
(PMD) variants and Ethernet interface types mandating auto-
negotiation (except 1000Base-X) are out of scope for this document.
All Ethernet services are leveraging the basic PLE payload and
interface specific
interface-specific mechanisms are confined to the respective service
specific NSP functions.
4.2.1. 1000BASE-X
The PCS layer of 1000BASE-X defined (defined in section Section 36 of [IEEE802.3] [IEEE802.3]) is
based on 8B/10B code.
The PSN-bound NSP function does not modify the received data and is
transparent to auto-negotiation but auto-negotiation; however, it is responsible to detect
1000BASE-X specific for
detecting attachment circuit faults specific to 1000BASE-X such as
LOS and sync loss.
When the CE-bound IWF is in PLOS state or when PLE packets are
received with the L-bit being L bit set, the CE-bound NSP function MAY disable
its transmitter as no appropriate maintenance signal was defined for
1000BASE-X by the IEEE.
4.2.2. 10GBASE-R and 25GBASE-R
The PCS layers of 10GBASE-R defined (defined in section Section 49 and 25GBASE-R
defined in section Section 107 of [IEEE802.3] [IEEE802.3]) are based on a 64B/66B code.
[IEEE802.3] sections
Sections 74 and 108 do of [IEEE802.3] define an optional FEC layer, layer; if
present
present, the PSN-bound NSP function MUST terminate the FEC and the CE-
bound
CE-bound NSP function MUST generate the FEC.
The PSN-bound NSP function is also responsible for detecting
attachment circuit faults specific to detect 10GBASE-R and 25GBASE-R specific attachment circuit faults such as
LOS and sync loss.
The PSN-bound IWF is mapping maps the scrambled 64B/66B code stream into the
basic PLE payload.
The CE-bound NSP function MUST perform perform:
* PCS code sync (section (Section 49.2.9 of [IEEE802.3])
* descrambling (section (Section 49.2.10 of [IEEE802.3])
in order to properly properly:
* transform invalid 66B code blocks into proper error control
characters /E/ (section (Section 49.2.4.11 of [IEEE802.3])
* insert Local Fault (LF) ordered sets (section (Section 46.3.4 of
[IEEE802.3]) when the CE-bound IWF is in PLOS state or when PLE
packets are received with the L-bit being set L bit set.
Note: Invalid 66B code blocks typically are a consequence of the CE-
bound IWF inserting replacement data in case of lost PLE packets, packets or
if
the far-end PSN-bound NSP function did set setting sync headers to 11 due to
uncorrectable FEC errors.
Before sending the bit stream to the CE, the CE-bound NSP function
MUST also scramble the 64B/66B code stream (section (Section 49.2.6
[IEEE802.3]).
4.2.3. 40GBASE-R, 50GBASE-R 50GBASE-R, and 100GBASE-R
The PCS layers of 40GBASE-R and 100GBASE-R defined (defined in section Section 82 of
[IEEE802.3]) and of 50GBASE-R defined (defined in section Section 133 of [IEEE802.3] [IEEE802.3])
are based on a 64B/66B code transmitted over multiple lanes.
[IEEE802.3] sections
Sections 74 and 91 do of [IEEE802.3] define an optional FEC layer, layer; if
present
present, the PSN-bound NSP function MUST terminate the FEC and the CE-
bound
CE-bound NSP function MUST generate the FEC.
To gain access to the scrambled 64B/66B code stream stream, the PSN-bound
NSP further MUST perform perform:
* block synchronization (section (Section 82.2.12 of [IEEE802.3])
* PCS lane de-skew (section (Section 82.2.13 of [IEEE802.3])
* PCS lane reordering (section (Section 82.2.14 of [IEEE802.3])
The PSN-bound NSP function is also responsible for detecting
attachment circuit faults specific to detect 40GBASE-R,
50GBASE-R 50GBASE-R, and
100GBASE-R specific attachment circuit faults such as LOS and loss of alignment.
The PSN-bound IWF is mapping maps the serialized and scrambled 64B/66B code
stream including the alignment markers into the basic PLE payload.
The CE-bound NSP function MUST perform perform:
* PCS code sync (section (Section 82.2.12 of [IEEE802.3])
* alignment marker alignment-marker removal (section (Section 82.2.15 of [IEEE802.3])
* descrambling (section (Section 49.2.10 of [IEEE802.3])
in order to properly properly:
* transform invalid 66B code blocks into proper error control
characters /E/ (section (Section 82.2.3.10 of [IEEE802.3])
* insert Local Fault (LF) ordered sets (section (Section 81.3.4 of
[IEEE802.3]) when the CE-bound IWF is in PLOS state or when PLE
packets are received with the L-bit being L bit set
Note: Invalid 66B code blocks typically are a consequence of the CE-
bound IWF inserting replacement data in case of lost PLE packets, packets or
if
the far-end PSN-bound NSP function did set not setting sync headers to 11 due
to uncorrectable FEC errors.
When sending the bit stream to the CE, the CE-bound NSP function MUST
also perform perform:
* scrambling of the 64B/66B code (section (Section 49.2.6 of [IEEE802.3])
* block distribution (section (Section 82.2.6 of [IEEE802.3])
* alignment marker alignment-marker insertion (sections (Sections 82.2.7 and 133.2.2 of
[IEEE802.3])
4.2.4. 200GBASE-R and 400GBASE-R
The PCS layers of 200GBASE-R and 400GBASE-R defined (defined in section Section 119
of
[IEEE802.3] [IEEE802.3]) are based on a 64B/66B code transcoded to a 256B/257B
code to reduce the overhead and make room for a mandatory FEC.
To gain access to the 64B/66B code stream stream, the PSN-bound NSP further
MUST perform perform:
* alignment lock and de-skew (section (Section 119.2.5.1 of [IEEE802.3])
* PCS Lane reordering and de-interleaving (section (Section 119.2.5.2 of
[IEEE802.3])
* FEC decoding (section (Section 119.2.5.3 of [IEEE802.3])
* post-FEC interleaving (section (Section 119.2.5.4 of [IEEE802.3])
* alignment marker alignment-marker removal (section (Section 119.2.5.5 of [IEEE802.3])
* descrambling (section (Section 119.2.5.6 of [IEEE802.3])
* reverse transcoding from 256B/257B to 64B/66B (section (Section 119.2.5.7
of [IEEE802.3])
Further
Further, the PSN-bound NSP MUST perform rate compensation and
scrambling (section (Section 49.2.6 of [IEEE802.3]) before the PSN-bound IWF
is mapping
maps the same into the basic PLE payload.
Rate compensation is applied so that the rate of the 66B encoded bit
stream carried by PLE is 528/544 times the nominal bitrate of the
200GBASE-R or 400GBASE-R at the PMA service interface. X number of
66 byte long
66-byte-long rate compensation blocks are inserted every X*20479
number of 66B client blocks. For 200GBASE-R 200GBASE-R, the value of X is 16 and 16;
for 400GBASE-R 400GBASE-R, the value of X is 32. Rate compensation blocks are
special 66B control characters of type 0x00 that can easily be
searched for by the CE-bound IWF in order to remove them.
The PSN-bound NSP function is also responsible for detecting
attachment circuit faults specific to detect 200GBASE-R and 400GBASE-R specific attachment circuit faults such
as LOS and loss of alignment.
The CE-bound NSP function MUST perform perform:
* PCS code sync (section (Section 49.2.13 of [IEEE802.3])
* descrambling (section (Section 49.2.10 of [IEEE802.3])
* rate compensation block removal
in order to properly properly:
* transform invalid 66B code blocks into proper error control
characters /E/ (section (Section 119.2.3.9 of [IEEE802.3])
* insert Local Fault (LF) ordered sets (section (Section 81.3.4 of
[IEEE802.3]) when the CE-bound IWF is in PLOS state or when PLE
packets are received with the L-bit being L bit set
Note: Invalid 66B code blocks typically are a consequence of the CE-
bound IWF inserting replacement data in case of lost PLE packets, packets or
if
the far-end PSN-bound NSP function did set not setting sync headers to 11 due
to uncorrectable FEC errors.
When sending the bit stream to the CE, the CE-bound NSP function MUST
also perform perform:
* transcoding from 64B/66B to 256B/257B (section (Section 119.2.4.2 of
[IEEE802.3])
* scrambling (section (Section 119.2.4.3 of [IEEE802.3])
* alignment marker alignment-marker insertion (section (Section 119.2.4.4 of [IEEE802.3])
* pre-FEC distribution (section (Section 119.2.4.5 of [IEEE802.3])
* FEC encoding (section (Section 119.2.4.6 of [IEEE802.3])
* PCS Lane distribution (section (Section 119.2.4.8 of [IEEE802.3])
4.2.5. Energy Efficient Ethernet (EEE)
Section 78 of [IEEE802.3] does define defines the optional Low Power Idle (LPI)
capability for Ethernet. Two modes are defined defined:
* deep sleep
* fast wake
Deep sleep mode is not compatible with PLE due to the CE ceasing
transmission. Hence Hence, there is no support for LPI for 10GBASE-R
services across PLE.
When in
In fast wake mode mode, the CE transmits /LI/ control code blocks instead
of /I/ control code blocks and therefore and, therefore, PLE is agnostic to it.
For 25GBASE-R and higher services across PLE, LPI is supported as
only fast wake mode is applicable.
4.3. SONET/SDH Services
SONET/SDH services are special cases of the structured bit stream
defined in Section 3.3.4 of [RFC3985].
SDH interfaces are defined in [G.707] and [G.707]; SONET interfaces are defined
in [GR253].
The PSN-bound NSP function does not modify the received data but is
responsible to detect SONET/SDH interface specific for detecting attachment circuit faults specific to
SONET/SDH such as LOS, LOF LOF, and OOF.
Data received by the PSN-bound IWF is mapped into the basic PLE
payload without any awareness of SONET/SDH frames.
When the CE-bound IWF is in PLOS state or when PLE packets are
received with the L-bit being L bit set, the CE-bound NSP function is responsible
for generating the the:
* MS-AIS maintenance signal defined (defined in section Section 6.2.4.1.1 of [G.707]
[G.707]) for SDH services
* AIS-L maintenance signal defined (defined in section Section 6.2.1.2 of [GR253] [GR253])
for SONET services
at client frame client-frame boundaries.
4.4. Fibre Channel Services
Fibre Channel services are special cases of the structured bit stream
defined in Section 3.3.4 of [RFC3985].
The T11 technical committee of INCITS has defined several layers for
Fibre Channel. PLE operates at the FC-1 layer that leverages
mechanisms defined by [IEEE802.3].
Over time time, many different Fibre Channel interface types have been
specified with a varying set of characteristics such as optional vs
versus mandatory FEC and single-lane vs versus multi-lane transmission.
Speed negotiation is not supported by PLE.
All Fibre Channel services are leveraging leverage the basic PLE payload payload, and
interface specific
interface-specific mechanisms are confined to the respective service service-
specific NSP functions.
4.4.1. 1GFC, 2GFC, 4GFC 4GFC, and 8GFC
[FC-PI-2] specifies 1GFC and 2GFC. [FC-PI-5] and [FC-PI-5am1] do define
4GFC and 8GFC.
The PSN-bound NSP function is responsible to detect Fibre Channel
specific for detecting attachment
circuit faults specific to the Fibre Channel such as LOS and sync
loss.
The PSN-bound IWF is mapping maps the received 8B/10B code stream as is directly
into the basic PLE payload.
The CE-bound NSP function MUST perform transmission word sync in
order to properly properly:
* replace invalid transmission words with the special character
K30.7
* insert Not Operational (NOS) ordered sets when the CE-bound IWF is
in PLOS state or when PLE packets are received with the L-bit
being L bit set
Note: Invalid transmission words typically are a consequence of the
CE-bound IWF inserting replacement data in case of lost PLE packets.
[FC-PI-5am1] does define defines the use of scrambling for 8GFC, 8GFC; in this case case,
the CE-bound NSP MUST also perform descrambling before replacing
invalid transmission words or inserting NOS ordered sets. And before Before
sending the bit stream to the, the CE, the CE-bound NSP function MUST
scramble the 8B/10B code stream.
4.4.2. 16GFC
[FC-PI-5] and [FC-PI-5am1] specify 16GFC and define a an optional FEC
layer.
If FEC is present present, it must be indicated via transmitter training
signal (TTS) during when the attachment circuit bring is brought up. Further Further, the PSN-
bound
PSN-bound NSP function MUST terminate the FEC and the CE-bound NSP
function must generate the FEC.
The PSN-bound NSP function is responsible to detect Fibre Channel
specific for detecting attachment
circuit faults specific to the Fibre Channel such as LOS and sync
loss.
The PSN-bound IWF is mapping maps the received scrambled 64B/66B code stream as
is into the basic PLE payload.
The CE-bound NSP function MUST perform perform:
* transmission word sync (section (Section 49.2.13 of [IEEE802.3])
* descrambling (section (Section 49.2.10 of [IEEE802.3])
in order to properly properly:
* replace invalid transmission words with the error transmission
word 1Eh
* insert Not Operational (NOS) ordered sets when the CE-bound IWF is
in PLOS state or when PLE packets are received with the L-bit
being L bit set
Note: Invalid transmission words typically are a consequence of the
CE-bound IWF inserting replacement data in case of lost PLE packets, packets
or if the far-end PSN-bound NSP function did set not setting sync headers to 11
due to uncorrectable FEC errors.
Before sending the bit stream to the CE, the CE-bound NSP function
MUST also scramble the 64B/66B code stream (section (Section 49.2.6 of
[IEEE802.3]).
4.4.3. 32GFC and 4-lane 4-Lane 128GFC
[FC-PI-6] specifies 32GFC and [FC-PI-6P] specifies 4-lane 128GFC,
both with FEC layer and TTS support being mandatory.
To gain access to the 64B/66B code stream the PSN-bound NSP further
MUST perform perform:
* descrambling (section (Section of 49.2.10 of [IEEE802.3])
* FEC decoding (section (Section 91.5.3.3 of [IEEE802.3])
* reverse transcoding from 256B/257B to 64B/66B (section (Section 119.2.5.7
of [IEEE802.3])
Further
Further, the PSN-bound NSP MUST perform scrambling (section (Section 49.2.6 of
[IEEE802.3]) before the PSN-bound IWF is mapping maps the same into the basic
PLE payload.
The PSN-bound NSP function is also responsible to detect Fibre
Channel specific for detecting
attachment circuit faults specific to the Fibre Channel such as LOS
and sync loss.
The CE-bound NSP function MUST perform perform:
* transmission word sync (section (Section 119.2.6.3 of [IEEE802.3])
* descrambling (section (Section 49.2.10 of [IEEE802.3])
in order to properly properly:
* replace invalid transmission words with the error transmission
word 1Eh
* insert Not Operational (NOS) ordered sets when the CE-bound IWF is
in PLOS state or when PLE packets are received with the L-bit
being L bit set
Note: Invalid transmission words typically are a consequence of the
CE-bound IWF inserting replacement data in case of lost PLE packets, packets
or if the far-end PSN-bound NSP function did set not setting sync headers to 11
due to uncorrectable FEC errors.
When sending the bit stream to the CE, the CE-bound NSP function MUST
also perform perform:
* transcoding from 64B/66B to 256B/257B (section (Section 119.2.4.2 of
[IEEE802.3])
* FEC encoding (section (Section 91.5.2.7 of [IEEE802.3])
* scrambling (section (Section 49.2.6 of [IEEE802.3])
4.4.4. 64GFC
[FC-PI-7] specifies 64GFC with a mandatory FEC layer.
To gain access to the 64B/66B code stream stream, the PSN-bound NSP further
MUST perform perform:
* alignment lock (section (Section 134.5.4 of [IEEE802.3] modified to single
FEC lane operation)
* FEC decoding (section (Section 134.5.3.3 of [IEEE802.3])
* alignment marker alignment-marker removal (section (Section 134.5.3.4 of [IEEE802.3])
* reverse transcoding from 256B/257B to 64B/66B (section (Section 91.5.3.5 of
[IEEE802.3])
Further
Further, the PSN-bound NSP MUST perform scrambling (section (Section 49.2.6 of
[IEEE802.3]) before the PSN-bound IWF is mapping maps the same into the basic
PLE payload.
The PSN-bound NSP function is also responsible to detect Fibre
Channel specific for detecting
attachment circuit faults specific to the Fibre Channel such as LOS
and sync loss.
The CE-bound NSP function MUST perform perform:
* transmission word sync (section (Section 49.2.13 of [IEEE802.3])
* descrambling (section (Section 49.2.10 of [IEEE802.3])
in order to properly properly:
* replace invalid transmission words with the error transmission
word 1Eh
* insert Not Operational (NOS) ordered sets when the CE-bound IWF is
in PLOS state or when PLE packets are received with the L-bit
being L bit set
Note: Invalid transmission words typically are a consequence of the
CE-bound IWF inserting replacement data in case of lost PLE packets, packets
or if the far-end PSN-bound NSP function did set not setting sync headers to 11
due to uncorrectable FEC errors.
When sending the bit stream to the CE, the CE-bound NSP function MUST
also perform perform:
* transcoding from 64B/66B to 256B/257B (section (Section 91.5.2.5 of
[IEEE802.3])
* alignment marker alignment-marker insertion (section (Section 134.5.2.6 of [IEEE802.3])
* FEC encoding (section (Section 134.5.2.7 of [IEEE802.3])
4.5. OTN Services
OTN services are special cases of the structured bit stream defined
in Section 3.3.4 of [RFC3985].
OTN interfaces are defined in [G.709].
The PSN-bound NSP function MUST terminate the FEC and replace the
OTUk overhead in row 1 1, columns 8-14 with an all-zeros pattern which pattern; this
results in a an extended ODUk frame as illustrated in Figure 3. The
frame alignment overhead (FA OH) in row 1 1, columns 1-7 is kept as it
is.
column #
1 7 8 14 15 3824
+--------+--------+------------------- .. --------------------+
1| FA OH | All-0s | |
+--------+--------+ |
r 2| | |
o | | |
w 3| ODUk overhead | |
# | | |
4| | |
+-----------------+------------------- .. --------------------+
Figure 3: Extended ODUk Frame
The PSN-bound NSP function is also responsible to detect OTUk
specific for detecting
attachment circuit faults specific to OTUk such as LOS, LOF, LOM LOM, and
AIS.
The PSN-bound IWF is mapping maps the extended ODUk frame into the byte
aligned byte-aligned
PLE payload.
The CE-bound NSP function will recover the ODUk by searching for the
frame alignment overhead in the extended ODUk received from the CE-
bound IWF and generates generating the FEC.
When the CE-bound IWF is in PLOS state or when PLE packets are
received with the L-bit being L bit set, the CE-bound NSP function is responsible
for generating the ODUk-AIS maintenance signal defined in
section
Section 16.5.1 of [G.709] at client frame client-frame boundaries.
5. PLE Encapsulation Layer
The basic packet format used by PLE is shown in the Figure 4.
+-------------------------------+ -+
| PSN and VPWS Demux | \
| (MPLS/SRv6) | > PSN and VPWS
| | / Demux Headers
+-------------------------------+ -+
| PLE Control Word | \
+-------------------------------+ > PLE Header
| RTP Header | /
+-------------------------------+ --+
| Bit Stream | \
| Payload | > Payload
| | /
+-------------------------------+ --+
Figure 4: PLE Encapsulation Layer
5.1. PSN and VPWS Demultiplexing Headers
This document does not imply suggest any specific technology to be used for
implementing the VPWS demultiplexing and PSN layers.
The total size of a PLE packet for a specific PW MUST NOT exceed the
path MTU between the pair of PEs terminating this PW.
When a an MPLS PSN layer is used, a VPWS label provides the
demultiplexing mechanism as (as described in Section 5.4.2 of [RFC3985].
[RFC3985]). The PSN tunnel can be a simple best path best-path Label Switched
Path (LSP) established using LDP [RFC5036] (see [RFC5036]) or Segment Routing
(SR) [RFC8402] (see [RFC8402]); or it can be a traffic engineered traffic-engineered LSP
established using RSVP-TE [RFC3209] (see [RFC3209]) or SR policies [RFC9256]. (see
[RFC9256]).
When a an SRv6 PSN layer is used, a an SRv6 service segment identifier Segment Identifier
(SID) as (as defined in [RFC8402] does provide [RFC8402]) provides the demultiplexing mechanism
and definitions of Section 6 of [RFC9252] do apply. Both SRv6 service
SIDs with the full IPv6 address format defined in [RFC8986] and
compressed SIDs (C-SIDs) with the format defined in
[I-D.draft-ietf-spring-srv6-srh-compression] [RFC9800] can be
used.
5.1.1. New SRv6 Behaviors
Two new encapsulation behaviors behaviors, H.Encaps.L1 and H.Encaps.L1.Red H.Encaps.L1.Red, are
defined in this document. The behavior procedures are applicable to
both SIDs and C-SIDs.
The H.Encaps.L1 behavior encapsulates a frame received from an IWF in
a
an IPv6 packet with an a segment routing header (SRH). The received
frame becomes the payload of the new IPv6 packet.
* The next header field of the SRH or the last extension header
present MUST be set to TBA1. 147.
* The insertion of the SRH MAY be omitted per [RFC8986] when the
SRv6 policy only contains one segment and there is no need to use
any flag, tag, or TLV.
The H.Encaps.L1.Red behavior is an optimization of the H.Encaps.L1
behavior.
* H.Encaps.L1.Red reduces the length of the SRH by excluding the
first SID in the SRH. The first SID is only placed in the
destination IPv6 address field.
* The insertion of the SRH MAY be omitted per [RFC8986] when the
SRv6 policy only contains one segment and there is no need to use
any flag, tag, or TLV.
Three new "Endpoint with decapsulation and bit-stream cross-connect"
behaviors called End.DX1, End.DX1 "End.DX1", "End.DX1 with NEXT-CSID NEXT-CSID", and End.DX1 "End.DX1
with
REPLACE-CSID REPLACE-CSID" are defined in this document. These new behaviors
are variants of End.DX2 defined in [RFC8986] [RFC8986], and they all have the
following procedures in common. common:
The End.DX1 SID MUST be the last segment in an SR Policy, and it is
associated with a CE-bound IWF I. When N receives a packet destined
to S and S is a local End.DX1 SID, N does the following:
S01. When an SRH is processed {
S02. If (Segments Left != 0) {
S03. Send an ICMP Parameter Problem to the Source Address
with Code 0 (Erroneous header field encountered)
and Pointer set to the Segments Left field,
interrupt packet processing, and discard the packet.
S04. }
S05. Proceed to process the next header in the packet
S06. }
When processing the next (Upper-Layer) header of a packet matching a
FIB entry locally instantiated as an End.DX1 SID, N does the
following:
S01. If (Upper-Layer header type == TBA1 147 (bit-stream) ) {
S02. Remove the outer IPv6 header with all its extension headers
S03. Forward the remaining frame to the IWF I
S04. } Else {
S05. Process as per {{Section 4.1.1 of RFC8986}} RFC 8986}}
S06. }
5.2. PLE Header
The PLE header MUST contain the PLE control word (4 bytes) and MUST
include a fixed size fixed-size RTP header [RFC3550]. The RTP header MUST
immediately follow the PLE control word.
5.2.1. PLE Control Word
The format of the PLE control word is in line with the guidance in
[RFC4385] and is shown in Figure 5.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0|L|R|RSV|FRG| LEN | Sequence number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: PLE Control Word
The bits 0..3 of the first nibble are set to 0 to differentiate a
control word or Associated Channel Header (ACH) from an IP packet or
Ethernet frame. The first nibble MUST be set to 0000b to indicate
that this header is a control word as defined in Section 3 of
[RFC4385].
The other fields in the control word are used as defined below:
*
L
Set by the PE to indicate that data carried in the payload is
invalid due to an attachment circuit fault. The downstream PE
MUST send appropriate replacement data. The NSP MAY inject an
appropriate native fault propagation signal.
*
R
Set by the downstream PE to indicate that the IWF experiences
packet loss from the PSN or a server layer backward fault
indication is present in the NSP. The R bit MUST be cleared by
the PE once the packet loss state or fault indication has cleared.
*
RSV
These bits are reserved for future use. This field MUST be set to
zero by the sender and ignored by the receiver.
*
FRG
These bits MUST be set to zero by the sender and ignored by the
receiver as PLE does not use payload fragmentation.
*
LEN
In accordance to with Section 3 of [RFC4385] [RFC4385], the length field MUST
always be set to zero as there is no padding added to the PLE
packet. To detect malformed packets the default, preconfigured or
signaled payload size MUST be assumed.
*
Sequence number
The sequence number field is used to provide a common PW
sequencing function as well as detection of lost packets. It MUST
be generated in accordance with the rules defined in Section 5.1
of [RFC3550] and MUST be incremented with every PLE packet being
sent.
5.2.2. RTP Header
The RTP header MUST be included to explicitly convey timing
information.
The RTP header as (as defined in [RFC3550] [RFC3550]) is reused to align with
other bit-stream emulation pseudowires defined by [RFC4553], [RFC5086]
[RFC5086], and [RFC4842] and to allow PLE implementations to reuse pre-existing
preexisting work.
There is no intention to support full RTP topologies and protocol
mechanisms, such as header extensions, contributing source (CSRC)
list, padding, RTP Control Protocol (RTCP), RTP header compression,
Secure Realtime Real-time Transport Protocol (SRTP), etc., as these are not
applicable to PLE VPWS.
The format of the RTP header is as shown in Figure 6.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|V=2|P|X| CC |M| PT | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Synchronization Source (SSRC) Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: RTP Header
*
V:
Version
The version field MUST be set to 2.
*
P:
Padding
The padding flag MUST be set to zero by the sender and ignored by
the receiver.
*
X:
Header extension
The X bit MUST be set to zero by sender and ignored by receiver.
*
CC:
CSRC count
The CC field MUST be set to zero by the sender and ignored by the
receiver.
*
M:
Marker
The M bit MUST be set to zero by the sender and ignored by the
receiver.
*
PT:
Payload type
A PT value MUST be allocated from the range of dynamic values
defined in Section 6 of [RFC3551] for each direction of the VPWS.
The same PT value MAY be reused both for direction and between
different PLE VPWS.
The PT field MAY be used for detection of misconnections.
*
Sequence number
When using a 16 bit 16-bit sequence number space, the sequence number in
the RTP header MUST be equal to the sequence number in the PLE
control word. When using a sequence number space of 32 bit, bits, the
initial value of the RTP sequence number MUST be 0 and incremented
whenever the PLE control word sequence number cycles through from
0xFFFF to 0x0000.
*
Timestamp
Timestamp values are used in accordance with the rules established
in [RFC3550]. For bit-streams up to 200 Gbps Gbps, the frequency of
the clock used for generating timestamps MUST be 125 MHz based on
a the common clock I. For bit-streams above 200 Gbps Gbps, the
frequency MUST be 250 MHz.
*
SSRC:
Synchronization source
The SSRC field MAY be used for detection of misconnections.
6. PLE Payload Layer
A bit-stream is mapped into a PLE packet with a fixed payload size size,
which MUST be defined during VPWS setup, MUST be the same in both
directions of the VPWS VPWS, and MUST remain unchanged for the lifetime of
the VPWS.
All PLE implementations MUST be capable of supporting the default
payload size of 1024 bytes. The payload size SHOULD be configurable
to be able to address specific packetization delay and overhead
expectations. The smallest supported payload size is 64 bytes.
6.1. Basic Payload
The PLE payload is filled with incoming bits of the bit-stream
starting from the most significant to the least significant bit
without considering any structure of the bit-stream.
6.2. Byte aligned Byte-Aligned Payload
The PLE payload is filled in a byte aligned byte-aligned manner, where the order
of the payload bytes corresponds to their order on the attachment
circuit. Consecutive bits coming from the attachment circuit fill
each payload byte starting from most significant bit to least
significant. The PLE payload size MUST be an integer number of
bytes.
7. PLE Operation
7.1. Common Considerations
A PLE VPWS can be established using manual configuration or
leveraging mechanisms of a signaling protocol.
Furthermore
Furthermore, emulation of bit-stream signals using PLE is only
possible when the two attachment circuits of the VPWS are of the same
service type (OC192, 10GBASE-R, ODU2, etc) etc.) and are using the same
PLE payload type and payload size. This can be ensured via manual
configuration or via the mechanisms of a signaling protocol.
PLE related
PLE-related control protocol extensions to LDP [RFC8077] or EVPN-VPWS
[RFC8214] are out of scope for this document.
Extensions for EVPN-VPWS are proposed in
[I-D.draft-schmutzer-bess-bitstream-vpws-signalling] [EVPN-VPWS] and for LDP in
[I-D.draft-schmutzer-pals-ple-signaling].
[LDP-PLE].
7.2. PLE IWF Operation
7.2.1. PSN-bound PSN-Bound Encapsulation Behavior
After the VPWS is set up, the PSN-bound IWF does perform performs the following
steps:
* Packetize the data received from the CE is into PLE payloads, all of
the same configured size
* Add PLE control word and RTP header with sequence numbers, flags flags,
and timestamps properly set
* Add the VPWS demultiplexer and PSN headers
* Transmit the resulting packets over the PSN
* Set the L bit in the PLE control word whenever the attachment
circuit detects a fault
* Set the R bit in the PLE control word whenever the local CE-bound
IWF is in packet loss state
7.2.2. CE-bound CE-Bound Decapsulation Behavior
The CE-bound IWF is responsible for removing the PSN and VPWS
demultiplexing headers, PLE control word word, and RTP header from the
received packet stream and sending the bit-stream out via the local
attachment circuit.
A de-jitter buffer MUST be implemented where the PLE packets are
stored upon arrival. The size of this buffer SHOULD be locally
configurable to allow accommodation of specific PSN packet delay
variation (PDV) expected.
The CE-bound IWF SHOULD use the sequence number in the control word
to detect lost and misordered packets. It MAY use the sequence
number in the RTP header for the same purposes. purpose. The CE-bound IWF MAY
support re-ordering reordering of packets received out of order. If the CE-
bound CE-bound
IWF does not support re-ordering reordering, it MUST drop the misordered packets.
The payload of a lost or dropped packet MUST be replaced with an
equivalent amount of replacement data. The contents of the
replacement data MAY be locally configurable. By default, all PLE
implementations MUST support generation of "0xAA" as replacement
data. The alternating sequence of 0s and 1s of the "0xAA" pattern
does ensure
ensures clock synchronization is maintained and and, for 64B/66B code code-
based services services, ensures no invalid sync headers are generated. While
sending out the replacement data, the IWF will apply a holdover
mechanism to maintain the clock.
Whenever the VPWS is not operationally up, the CE-bound NSP function
MUST inject the appropriate native downstream fault indication fault-indication
signal.
Whenever a VPWS comes up, the CE-bound IWF enters will enter the
intermediate state, will start receiving PLE packets packets, and will store
them in the jitter buffer. The CE-bound NSP function will continue
to inject the appropriate native downstream fault indication fault-indication signal
until a pre-
configured preconfigured number of payload s stored in the jitter
buffer.
After the pre-configured preconfigured amount of payload is present in the jitter
buffer
buffer, the CE-bound IWF transitions to the normal operation state state,
and the content of the jitter buffer is streamed out to the CE in
accordance with the required clock. In this state state, the CE-bound IWF
MUST perform egress clock recovery.
Considerations for choosing the pre-configured preconfigured amount of payload
required to be present for transitioning into the normal state:
* Typically set to 50% of the de-jitter buffer size to equally allow
compensating for increasing and decreasing delay
* Choosing a A compromise between the maximum amount of tolerable PDV and delay
introduced to the emulated service
The recovered clock MUST comply with the jitter and wander
requirements applicable to the type of attachment circuit, specified
in:
* [G.825], [G.783] [G.783], and [G.823] for SDH
* [GR253] and [GR499] for SONET
* [G.8261] for synchronous Ethernet
* [G.8251] for OTN
Whenever the L bit is set in the PLE control word of a received PLE
packet
packet, the CE-bound NSP function SHOULD inject the appropriate
native downstream fault indication fault-indication signal instead of streaming out
the payload.
If the CE-bound IWF detects loss of consecutive packets for a pre-
configured
preconfigured amount of time (default is 1 millisecond), it enters
packet loss (PLOS) state and a corresponding defect is declared.
If the CE-bound IWF detects a packet loss ratio (PLR) above a
configurable signal-degrade (SD) threshold for a configurable amount
of consecutive 1-second intervals, it enters the degradation (DEG)
state and a corresponding defect is declared. The SD-PLR threshold
can be defined as a percentage with the default being 15% or absolute
packet count for finer granularity for higher rate interfaces.
Possible values for consecutive intervals are 2..10 with the default
7.
While the PLOS defect is declared declared, the CE-bound NSP function MUST
inject the appropriate native downstream fault indication fault-indication signal. If
the emulated service does not have a an appropriate maintenance signal
defined, the CE-bound NSP function MAY disable its transmitter
instead. Also Also, the PSN-bound IWF SHOULD set the R bit in the PLE
control word of every packet transmitted.
The CE-bound IWF does change changes from the PLOS to normal state after the
pre-configured
preconfigured amount of payload has been received similarly similar to the
transition from intermediate to normal state.
Whenever the R bit is set in the PLE control word of a received PLE
packet
packet, the PLE performance monitoring statistics SHOULD get updated.
7.3. PLE Performance Monitoring
Attachment circuit performance monitoring SHOULD be provided by the
NSP. The performance monitors are service specific, documented in
related specifications specifications, and beyond the scope of this document.
The PLE IWF SHOULD provide functions to monitor the network
performance to be inline with expectations of transport network
operators.
The near-end performance monitors defined for PLE are as follows:
* ES-PLE : PLE Errored Seconds
* SES-PLE : PLE Severely Errored Seconds
* UAS-PLE : PLE Unavailable Seconds
Each second with at least one packet lost or a PLOS/DEG defect SHALL
be counted as an ES-PLE. Each second with a PLR greater than 15% or
a PLOS/DEG defect SHALL be counted as an SES-PLE.
UAS-PLE SHALL be counted after a configurable number of consecutive
SES-PLE
SES-PLEs have been observed, and no longer counted after a
configurable number of consecutive seconds without an SES-PLE have
been observed. Default The default value for each is 10 seconds.
Once unavailability is detected, ES and SES counts SHALL be inhibited
up to the point where the unavailability was started. Once
unavailability is removed, ES and SES that occurred along the
clearing period SHALL be added to the ES and SES counts.
A PLE far-end performance monitor is providing provides insight into the CE-
bound CE-bound
IWF at the far end of the PSN. The statistics are based on the
PLE-RDI PLE-
RDI indication carried in the PLE control word via the R bit.
The PLE VPWS performance monitors are derived from the definitions in
accordance with [G.826] [G.826].
Performance monitoring data MUST be provided by the management
interface and SHOULD be provided by a YANG data model. The YANG data
model specification is out of scope for this document.
7.4. PLE Fault Management
Attachment circuit faults applicable to PLE are detected by the NSP,
are service specific specific, and are documented in relevant section of Section 4.
The two PLE faults, PLOS and DEG DEG, are detected by the IWF.
Faults MUST be time stamped timestamped as they are declared and cleared and
fault cleared; fault-
related information MUST be provided by the management interface and
SHOULD be provided by a YANG data model. The YANG data model
specification is out of scope for this document.
8. QoS and Congestion Control
The PSN carrying PLE VPWS may be subject to congestion. Congestion
considerations for PWs are described in Section 6.5 of [RFC3985].
PLE VPWS represent inelastic constant bit-rate (CBR) flows that
cannot respond to congestion in a TCP-friendly manner as (as described
in
[RFC2914] [RFC2914]) and are sensitive to jitter, packet loss loss, and packets
received out of order.
The PSN providing connectivity between PE devices of a PLE VPWS has
to ensure low jitter and low loss. The exact mechanisms used are
beyond the scope of this document and may evolve over time. Possible
options, but not exhaustively, are as follows
* a Diffserv-enabled [RFC2475] PSN with a per domain per-domain behavior [RFC3086] (see
[RFC3086]) supporting Expedited Forwarding
[RFC3246]. Traffic-engineered (see [RFC3246]),
* traffic-engineered paths through the PSN with bandwidth
reservation and admission control applied. Or applied, or
* capacity over-
provisioning. over-provisioning.
9. Security Considerations
As PLE is leveraging VPWS as transport mechanism, the security
considerations described in [RFC3985] are applicable.
PLE does not enhance or detract from the security performance of the
underlying PSN. It relies upon the PSN mechanisms for encryption,
integrity, and authentication whenever required.
The PSN (MPLS or SRv6) is assumed to be trusted and secure.
Attackers who manage to send spoofed packets into the PSN could
easily disrupt the PLE service. This MUST be prevented by following
best practices for the isolation of the PSN. These protections are
described in the considerations in Section 3.4 of [RFC4381], Section 4.2 of [RFC5920] in [RFC5920],
Section 8 of [RFC8402] [RFC8402], and Section 9.3 of [RFC9252].
PLE PWs share susceptibility to a number of pseudowire-layer attacks
and will use whatever mechanisms for confidentiality, integrity, and
authentication that are developed for general PWs. These methods are
beyond the scope of this document.
Random initialization of sequence numbers, in both the control word
and the RTP header, makes known-plaintext attacks more difficult.
Misconnection detection using the SSRC and/or PT field of the RTP
header can increase the resilience to misconfiguration and some types
of denial-of-service (DoS) attacks. Randomly chosen expected values
do
decrease the chance of a spoofing attack being successful.
A data plane attack may force PLE packets to be dropped, re-ordered reordered,
or delayed beyond the limit of the CE-bound IWF's dejitter buffer
leading to either degradation or service disruption. Considerations
outlined in [RFC9055] are a good reference.
Clock synchronization leveraging PTP is sensitive to Packet Delay
Variation (PDV) and vulnerable to various threads and attack vectors.
Considerations outlined in [RFC7384] should be taken into account.
10. IANA Considerations
10.1. Bit-stream Bit-Stream Next Header Type
This document introduces a new value to be used in the next header
field of an IPv6 header or any extension header indicating that the
payload is a an emulated bit-stream. IANA is requested to assign has assigned the following
from the "Assigned Internet Protocol Numbers" registry [IANA-Proto].
+=========+=========+============+================+===========+
| Decimal | Keyword | Protocol | IPv6 Extension | Reference |
| | | | Header | |
+=========+=========+============+================+===========+
| TBA1 147 | BIT-EMU | Bit-stream | Y | this This |
| | | Emulation | | document |
+---------+---------+------------+----------------+-----------+
Table 1
10.2. SRv6 Endpoint Behaviors
This document introduces three new SRv6 Endpoint behaviors. IANA is
requested to assign has
assigned identifier values in the "SRv6 Endpoint Behaviors" sub-registry registry
under the "Segment Routing" registry group [IANA-SRv6-End].
+=======+========+===========================+===============+
| Value | Hex | Endpoint Behavior | Reference |
+=======+========+===========================+===============+
| 158 | 0x009E | End.DX1 | this This document |
+-------+--------+---------------------------+---------------+
| 159 | 0x009F | End.DX1 with NEXT-CSID | this This document |
+-------+--------+---------------------------+---------------+
| 160 | 0x00A0 | End.DX1 with REPLACE-CSID | this This document |
+-------+--------+---------------------------+---------------+
Table 2
11. Acknowledgements
The authors would like to thank Alexander Vainshtein, Yaakov Stein,
Erik van Veelen, Faisal Dada, Giles Heron, Luca Della Chiesa and
Ashwin Gumaste for their early contributions, review, comments and
suggestions.
Special thank you to
* Carlos Pignataro and Nagendra Kumar Nainar for giving the authors
new to IETF guidance on how to get started
* Stewart Bryant for being our shepherd
* Tal Mizahi, Joel Halpern, Christian Huitema, Tony Li, Tommy Pauly
for their reviews and suggestions during last call
* Andrew Malis and Gunter van de Velde for their guidance through
the process
12. References
12.1.
11.1. Normative References
[G.707] International Telecommunication Union (ITU), ITU-T, "Network node interface for the synchronous digital
hierarchy (SDH)", ITU-T Recommendation G.707, January
2007, <https://www.itu.int/rec/T-REC-G.707>.
[G.709] International Telecommunication Union (ITU), ITU-T, "Interfaces for the optical transport network",
ITU-T Recommendation G.709, June 2020,
<https://www.itu.int/rec/T-REC-G.709>.
[G.783] International Telecommunication Union (ITU), ITU-T, "Characteristics of synchronous digital hierarchy
(SDH) equipment functional blocks", ITU-T
Recommendation G.783, March 2006,
<https://www.itu.int/rec/T-REC-G.783>.
[G.823] International Telecommunication Union (ITU), ITU-T, "The control of jitter and wander within digital
networks which are based on the 2048 kbit/s hierarchy",
ITU-T Recommendation G.823, March 2000,
<https://www.itu.int/rec/T-REC-G.823>.
[G.824] International Telecommunication Union (ITU), ITU-T, "The control of jitter and wander within digital
networks which are based on the 1544 kbits hierarchy",
ITU-T Recommendation G.824, March 2000,
<https://www.itu.int/rec/T-REC-G.824>.
[G.825] International Telecommunication Union (ITU), ITU-T, "The control of jitter and wander within digital
networks which are based on the synchronous digital
hierarchy (SDH)", ITU-T Recommendation G.825, March 2000,
<https://www.itu.int/rec/T-REC-G.825>.
[G.8251] International Telecommunication Union (ITU), ITU-T, "The control of jitter and wander within the
optical transport network (OTN)", ITU-T
Recommendation G.8251, November 2022,
<https://www.itu.int/rec/T-REC-G.8251>.
[G.8261] International Telecommunication Union (ITU), ITU-T, "Timing and synchronization aspects in packet
networks", ITU-T Recommendation G.8261, August 2019,
<https://www.itu.int/rec/T-REC-G.8261>.
[G.8261.1] International Telecommunication Union (ITU), ITU-T, "Packet delay variation network limits applicable
to packet-based methods (Frequency synchronization)",
ITU-T Recommendation G.8261.1, February 2012,
<https://www.itu.int/rec/T-REC-G.8261.1>.
[G.8262] International Telecommunication Union (ITU), ITU-T, "Timing characteristics of synchronous equipment slave clock",
November 2018,
clocks", ITU-T Recommendation G.8262, October 2024,
<https://www.itu.int/rec/T-REC-G.8262>.
[G.8265.1] International Telecommunication Union (ITU), ITU-T, "Precision time protocol telecom profile for
frequency synchronization", ITU-T Recommendation G.8265.1,
November 2022, <https://www.itu.int/rec/T-REC-G.8265.1>.
[GR253] Telcordia, "SONET "Synchronous Optical Network (SONET) Transport Systems -
Systems: Common Generic Criteria", GR-253, October 2009, <https://telecom-
info.njdepot.ericsson.net/site-cgi/ido/
<https://telecom-info.njdepot.ericsson.net/site-cgi/ido/
docs.cgi?ID=2111701336SEARCH&DOCUMENT=GR-253>.
[GR499] Telcordia, "Transport Systems Generic Requirements (TSGR)
- Common Requirements", GR-499, November 2009, <https://telecom-
info.njdepot.ericsson.net/site-cgi/ido/
<https://telecom-info.njdepot.ericsson.net/site-cgi/ido/
docs.cgi?ID=2111701336SEARCH&DOCUMENT=GR-499>.
[I-D.draft-ietf-spring-srv6-srh-compression]
Cheng, W., Filsfils, C., Li, Z., Decraene, B., and F.
Clad, "Compressed SRv6 Segment List Encoding (CSID)", Work
in Progress, Internet-Draft, draft-ietf-spring-srv6-srh-
compression-23, 6 February 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-spring-
srv6-srh-compression-23>.
[IANA-Proto]
IETF, "IANA
IANA, "Assigned Internet Protocol Numbers" sub-
registry", n.d., <https://www.iana.org/assignments/
protocol-numbers/protocol-numbers.xhtml#protocol-numbers-
1>. Numbers",
<https://www.iana.org/assignments/protocol-numbers>.
[IANA-SRv6-End]
IETF, "IANA
IANA, "SRv6 Endpoint Behaviors" sub-registry", n.d.,
<https://www.iana.org/assignments/segment-routing/segment-
routing.xhtml#srv6-endpoint-behaviors>. Behaviors",
<https://www.iana.org/assignments/segment-routing>.
[IEEE802.3]
IEEE, "IEEE Standard for Ethernet", May IEEE Std 802.3-2022,
DOI 10.1109/IEEESTD.2022.9844436, July 2022,
<https://standards.ieee.org/ieee/802.3/10422/>.
<https://ieeexplore.ieee.org/document/9844436>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V.
Jacobson, "RTP: A Transport Protocol for Real-Time
Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550,
July 2003, <https://www.rfc-editor.org/rfc/rfc3550>. <https://www.rfc-editor.org/info/rfc3550>.
[RFC3551] Schulzrinne, H. and S. Casner, "RTP Profile for Audio and
Video Conferences with Minimal Control", STD 65, RFC 3551,
DOI 10.17487/RFC3551, July 2003,
<https://www.rfc-editor.org/rfc/rfc3551>.
<https://www.rfc-editor.org/info/rfc3551>.
[RFC3985] Bryant, S., Ed. and P. Pate, Ed., "Pseudo Wire Emulation
Edge-to-Edge (PWE3) Architecture", RFC 3985,
DOI 10.17487/RFC3985, March 2005,
<https://www.rfc-editor.org/rfc/rfc3985>.
<https://www.rfc-editor.org/info/rfc3985>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>. <https://www.rfc-editor.org/info/rfc8174>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/rfc/rfc8402>. <https://www.rfc-editor.org/info/rfc8402>.
[RFC8986] Filsfils, C., Ed., Camarillo, P., Ed., Leddy, J., Voyer,
D., Matsushima, S., and Z. Li, "Segment Routing over IPv6
(SRv6) Network Programming", RFC 8986,
DOI 10.17487/RFC8986, February 2021,
<https://www.rfc-editor.org/rfc/rfc8986>.
<https://www.rfc-editor.org/info/rfc8986>.
[RFC9252] Dawra, G., Ed., Talaulikar, K., Ed., Raszuk, R., Decraene,
B., Zhuang, S., and J. Rabadan, "BGP Overlay Services
Based on Segment Routing over IPv6 (SRv6)", RFC 9252,
DOI 10.17487/RFC9252, July 2022,
<https://www.rfc-editor.org/rfc/rfc9252>.
12.2.
<https://www.rfc-editor.org/info/rfc9252>.
[RFC9800] Cheng, W., Ed., Filsfils, C., Li, Z., Decraene, B., and F.
Clad, Ed., "Compressed SRv6 Segment List Encoding (CSID)",
RFC 9800, DOI 10.17487/RFC9800, June 2025,
<https://www.rfc-editor.org/info/rfc9800>.
11.2. Informative References
[ATIS-0900105.09.2013]
ATIS, "Synchronous Optical Network (SONET) - Network
Element Timing and Synchronization", 2013, ATIS-
0900105.09.2013(S2023), 2023,
<https://webstore.ansi.org/standards/atis/
atis0900105092013s2023>.
[EVPN-VPWS]
Gringeri, S., Whittaker, J., Schmutzer, C., Ed.,
Vasudevan, B., and P. Brissette, "Ethernet VPN Signalling
Extensions for Bit-stream VPWS", Work in Progress,
Internet-Draft, draft-schmutzer-bess-bitstream-vpws-
signalling-02, 18 October 2024,
<https://datatracker.ietf.org/doc/html/draft-schmutzer-
bess-bitstream-vpws-signalling-02>.
[FC-PI-2] INCITS, "Information Technology - Fibre Channel Physical
Interfaces - 2 (FC-PI-2)", 2006, INCITS 404-2006 (S2016), 2016,
<https://webstore.ansi.org/standards/incits/
incits4042006>.
incits4042006s2016>.
[FC-PI-5] INCITS, "Information Technology - Fibre Channel - Physical
Interface-5 (FC-PI-5)", INCITS 479-2011, 2011,
<https://webstore.ansi.org/standards/incits/
incits4792011>.
[FC-PI-5am1]
INCITS, "Information Technology - Fibre Channel - Physical
Interface - 5/Amendment 1 (FC-PI-5/AM1)",
INCITS 479-2011/AM1-2016, 2016,
<https://webstore.ansi.org/standards/incits/
incits4792011am12016>.
[FC-PI-6] INCITS, "Information Technology - Fibre Channel - Physical
Interface - 6 (FC-PI-6)", INCITS 512-2015, 2015,
<https://webstore.ansi.org/standards/incits/
incits5122015>.
[FC-PI-6P] INCITS, "Information Technology - Fibre Channel - Physical
Interface - 6P (FC-PI-6P)", INCITS 533-2016, 2016,
<https://webstore.ansi.org/standards/incits/
incits5332016>.
[FC-PI-7] INCITS, ISO/IEC, "Information Technology technology – Fibre Channel channel - Part
147: Physical
Interfaces interfaces - 7 (FC-PI-7)", ISO/
IEC 14165-147:2021, 2021,
<https://webstore.ansi.org/standards/iso/
isoiec141651472021>.
<https://www.iso.org/standard/80933.html>.
[G.826] International Telecommunication Union (ITU), ITU-T, "End-to-end error performance parameters and
objectives for international, constant bit-rate digital
paths and connections", ITU-T Recommendation G.826,
December 2002, <https://www.itu.int/rec/T-REC-G.826>.
[I-D.draft-schmutzer-bess-bitstream-vpws-signalling]
Gringeri, S., Whittaker, J., Schmutzer, C., Vasudevan, B.,
and P. Brissette, "Ethernet VPN Signalling Extensions for
Bit-stream VPWS", Work in Progress, Internet-Draft, draft-
schmutzer-bess-bitstream-vpws-signalling-02, 18 October
2024, <https://datatracker.ietf.org/doc/html/draft-
schmutzer-bess-bitstream-vpws-signalling-02>.
[I-D.draft-schmutzer-pals-ple-signaling]
[LDP-PLE] Schmutzer, C., Ed., "LDP Extensions to Support Private
Line Emulation (PLE)", Work in Progress, Internet-Draft, draft-
schmutzer-pals-ple-signaling-02,
draft-schmutzer-pals-ple-signaling-02, 20 October 2024,
<https://datatracker.ietf.org/doc/html/draft-schmutzer-
pals-ple-signaling-02>.
[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
and W. Weiss, "An Architecture for Differentiated
Services", RFC 2475, DOI 10.17487/RFC2475, December 1998,
<https://www.rfc-editor.org/rfc/rfc2475>.
<https://www.rfc-editor.org/info/rfc2475>.
[RFC2914] Floyd, S., "Congestion Control Principles", BCP 41,
RFC 2914, DOI 10.17487/RFC2914, September 2000,
<https://www.rfc-editor.org/rfc/rfc2914>.
<https://www.rfc-editor.org/info/rfc2914>.
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001,
<https://www.rfc-editor.org/rfc/rfc3031>.
<https://www.rfc-editor.org/info/rfc3031>.
[RFC3086] Nichols, K. and B. Carpenter, "Definition of
Differentiated Services Per Domain Behaviors and Rules for
their Specification", RFC 3086, DOI 10.17487/RFC3086,
April 2001, <https://www.rfc-editor.org/rfc/rfc3086>. <https://www.rfc-editor.org/info/rfc3086>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<https://www.rfc-editor.org/rfc/rfc3209>.
<https://www.rfc-editor.org/info/rfc3209>.
[RFC3246] Davie, B., Charny, A., Bennet, J.C.R., Benson, K., Le
Boudec, J.Y., Courtney, W., Davari, S., Firoiu, V., and D.
Stiliadis, "An Expedited Forwarding PHB (Per-Hop
Behavior)", RFC 3246, DOI 10.17487/RFC3246, March 2002,
<https://www.rfc-editor.org/rfc/rfc3246>.
<https://www.rfc-editor.org/info/rfc3246>.
[RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
Norrman, "The Secure Real-time Transport Protocol (SRTP)",
RFC 3711, DOI 10.17487/RFC3711, March 2004,
<https://www.rfc-editor.org/rfc/rfc3711>.
<https://www.rfc-editor.org/info/rfc3711>.
[RFC4197] Riegel, M., Ed., "Requirements for Edge-to-Edge Emulation
of Time Division Multiplexed (TDM) Circuits over Packet
Switching Networks", RFC 4197, DOI 10.17487/RFC4197,
October 2005, <https://www.rfc-editor.org/rfc/rfc4197>. <https://www.rfc-editor.org/info/rfc4197>.
[RFC4381] Behringer, M., "Analysis of the Security of BGP/MPLS IP
Virtual Private Networks (VPNs)", RFC 4381,
DOI 10.17487/RFC4381, February 2006,
<https://www.rfc-editor.org/rfc/rfc4381>.
<https://www.rfc-editor.org/info/rfc4381>.
[RFC4385] Bryant, S., Swallow, G., Martini, L., and D. McPherson,
"Pseudowire Emulation Edge-to-Edge (PWE3) Control Word for
Use over an MPLS PSN", RFC 4385, DOI 10.17487/RFC4385,
February 2006, <https://www.rfc-editor.org/rfc/rfc4385>. <https://www.rfc-editor.org/info/rfc4385>.
[RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet
Control Message Protocol (ICMPv6) for the Internet
Protocol Version 6 (IPv6) Specification", STD 89,
RFC 4443, DOI 10.17487/RFC4443, March 2006,
<https://www.rfc-editor.org/rfc/rfc4443>.
<https://www.rfc-editor.org/info/rfc4443>.
[RFC4448] Martini, L., Ed., Rosen, E., El-Aawar, N., and G. Heron,
"Encapsulation Methods for Transport of Ethernet over MPLS
Networks", RFC 4448, DOI 10.17487/RFC4448, April 2006,
<https://www.rfc-editor.org/rfc/rfc4448>.
<https://www.rfc-editor.org/info/rfc4448>.
[RFC4553] Vainshtein, A., Ed. and YJ. Stein, Ed., "Structure-
Agnostic Time Division Multiplexing (TDM) over Packet
(SAToP)", RFC 4553, DOI 10.17487/RFC4553, June 2006,
<https://www.rfc-editor.org/rfc/rfc4553>.
<https://www.rfc-editor.org/info/rfc4553>.
[RFC4842] Malis, A., Pate, P., Cohen, R., Ed., and D. Zelig,
"Synchronous Optical Network/Synchronous Digital Hierarchy
(SONET/SDH) Circuit Emulation over Packet (CEP)",
RFC 4842, DOI 10.17487/RFC4842, April 2007,
<https://www.rfc-editor.org/rfc/rfc4842>.
<https://www.rfc-editor.org/info/rfc4842>.
[RFC4875] Aggarwal, R., Ed., Papadimitriou, D., Ed., and S.
Yasukawa, Ed., "Extensions to Resource Reservation
Protocol - Traffic Engineering (RSVP-TE) for Point-to-
Multipoint TE Label Switched Paths (LSPs)", RFC 4875,
DOI 10.17487/RFC4875, May 2007,
<https://www.rfc-editor.org/rfc/rfc4875>.
<https://www.rfc-editor.org/info/rfc4875>.
[RFC4906] Martini, L., Ed., Rosen, E., Ed., and N. El-Aawar, Ed.,
"Transport of Layer 2 Frames Over MPLS", RFC 4906,
DOI 10.17487/RFC4906, June 2007,
<https://www.rfc-editor.org/rfc/rfc4906>.
<https://www.rfc-editor.org/info/rfc4906>.
[RFC5036] Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed.,
"LDP Specification", RFC 5036, DOI 10.17487/RFC5036,
October 2007, <https://www.rfc-editor.org/rfc/rfc5036>. <https://www.rfc-editor.org/info/rfc5036>.
[RFC5086] Vainshtein, A., Ed., Sasson, I., Metz, E., Frost, T., and
P. Pate, "Structure-Aware Time Division Multiplexed (TDM)
Circuit Emulation Service over Packet Switched Network
(CESoPSN)", RFC 5086, DOI 10.17487/RFC5086, December 2007,
<https://www.rfc-editor.org/rfc/rfc5086>.
<https://www.rfc-editor.org/info/rfc5086>.
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010,
<https://www.rfc-editor.org/rfc/rfc5920>.
<https://www.rfc-editor.org/info/rfc5920>.
[RFC7212] Frost, D., Bryant, S., and M. Bocci, "MPLS Generic
Associated Channel (G-ACh) Advertisement Protocol",
RFC 7212, DOI 10.17487/RFC7212, June 2014,
<https://www.rfc-editor.org/rfc/rfc7212>.
<https://www.rfc-editor.org/info/rfc7212>.
[RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in
Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384,
October 2014, <https://www.rfc-editor.org/rfc/rfc7384>. <https://www.rfc-editor.org/info/rfc7384>.
[RFC8077] Martini, L., Ed. and G. Heron, Ed., "Pseudowire Setup and
Maintenance Using the Label Distribution Protocol (LDP)",
STD 84, RFC 8077, DOI 10.17487/RFC8077, February 2017,
<https://www.rfc-editor.org/rfc/rfc8077>.
<https://www.rfc-editor.org/info/rfc8077>.
[RFC8214] Boutros, S., Sajassi, A., Salam, S., Drake, J., and J.
Rabadan, "Virtual Private Wire Service Support in Ethernet
VPN", RFC 8214, DOI 10.17487/RFC8214, August 2017,
<https://www.rfc-editor.org/rfc/rfc8214>.
<https://www.rfc-editor.org/info/rfc8214>.
[RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
(SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
<https://www.rfc-editor.org/rfc/rfc8754>.
<https://www.rfc-editor.org/info/rfc8754>.
[RFC9055] Grossman, E., Ed., Mizrahi, T., and A. Hacker,
"Deterministic Networking (DetNet) Security
Considerations", RFC 9055, DOI 10.17487/RFC9055, June
2021, <https://www.rfc-editor.org/rfc/rfc9055>. <https://www.rfc-editor.org/info/rfc9055>.
[RFC9256] Filsfils, C., Talaulikar, K., Ed., Voyer, D., Bogdanov,
A., and P. Mattes, "Segment Routing Policy Architecture",
RFC 9256, DOI 10.17487/RFC9256, July 2022,
<https://www.rfc-editor.org/rfc/rfc9256>.
<https://www.rfc-editor.org/info/rfc9256>.
[RFC9293] Eddy, W., Ed., "Transmission Control Protocol (TCP)",
STD 7, RFC 9293, DOI 10.17487/RFC9293, August 2022,
<https://www.rfc-editor.org/rfc/rfc9293>.
<https://www.rfc-editor.org/info/rfc9293>.
[T11] INCITS, "T11 - Fibre Channel", n.d.,
<https://www.incits.org/committees/t11>.
Acknowledgements
The authors would like to thank Alexander Vainshtein, Yaakov Stein,
Erik van Veelen, Faisal Dada, Giles Heron, Luca Della Chiesa, and
Ashwin Gumaste for their early contributions, review, comments, and
suggestions.
Special thank you to:
* Carlos Pignataro and Nagendra Kumar Nainar for giving the authors
new-to-the-IETF guidance on how to get started
* Stewart Bryant for being our shepherd
* Tal Mizahi, Joel Halpern, Christian Huitema, Tony Li, and Tommy
Pauly for their reviews and suggestions during Last Call
* Andrew Malis and Gunter van de Velde for their guidance through
the process
Contributors
Andreas Burk
1&1 Versatel
Email: andreas.burk@magenta.de
Faisal Dada
AMD
Email: faisal.dada@amd.com
Gerald Smallegange
Ciena Corporation
Email: gsmalleg@ciena.com
Erik van Veelen
Aimvalley
Email: erik.vanveelen@aimvalley.com
Luca Della Chiesa
Cisco Systems, Inc.
Email: ldellach@cisco.com
Nagendra Kumar Nainar
Cisco Systems, Inc.
Email: naikumar@cisco.com
Carlos Pignataro
Blue Fern Consulting
Email: Carlos@Bluefern.consulting
Authors' Addresses
Steven Gringeri
Verizon
Email: steven.gringeri@verizon.com
Jeremy Whittaker
Verizon
Email: jeremy.whittaker@verizon.com
Nicolai Leymann
Deutsche Telekom
Email: N.Leymann@telekom.de
Christian Schmutzer (editor)
Cisco Systems, Inc.
Email: cschmutz@cisco.com
Chris Brown
Ciena Corporation
Email: cbrown@ciena.com