draft-ietf-ccamp-gmpls-otn-b100g-applicability-01.txt   draft-ietf-ccamp-gmpls-otn-b100g-applicability-02.txt 
Internet Engineering Task Force Q. Wang, Ed. Internet Engineering Task Force Q. Wang, Ed.
Internet-Draft ZTE Internet-Draft ZTE Corporation
Intended status: Informational R. Valiveti, Ed. Intended status: Informational R. Valiveti, Ed.
Expires: January 8, 2020 Infinera Corp Expires: September 7, 2020 Infinera Corp
H. Zheng, Ed. H. Zheng, Ed.
Huawei Huawei
H. Helvoort H. Helvoort
Hai Gaoming B.V Hai Gaoming B.V
S. Belotti S. Belotti
Nokia Nokia
July 7, 2019 March 6, 2020
Applicability of GMPLS for B100G Optical Transport Network Applicability of GMPLS for B100G Optical Transport Network
draft-ietf-ccamp-gmpls-otn-b100g-applicability-01 draft-ietf-ccamp-gmpls-otn-b100g-applicability-02
Abstract Abstract
This document examines the applicability of using current existing This document examines the applicability of using current existing
GMPLS routing and signaling to set up ODUk/ODUflex over ODUCn link, GMPLS routing and signaling to set up ODUk/ODUflex over ODUCn link,
as a result of the support of OTU/ODU links with rates larger than as a result of the introduction of OTU/ODU links with rates larger
100G in the 2016 version of G.709. than 100G in the 2016 version of G.709.
Status of This Memo Status of This Memo
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. OTN terminology used in this document . . . . . . . . . . . . 3
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2.2. OTN terminology used in this document . . . . . . . . . . 3
3. Overview of B100G in G.709 . . . . . . . . . . . . . . . . . 4 3. Overview of B100G in G.709 . . . . . . . . . . . . . . . . . 4
3.1. OTUCn . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.1. OTUCn . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1.1. Carrying OTUCn between 3R points . . . . . . . . . . 5
3.2. ODUCn . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.2. ODUCn . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. OTUCn-M . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.3. OTUCn-M . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.4. Time Slot Granularity . . . . . . . . . . . . . . . . . . 8 3.4. Time Slot Granularity . . . . . . . . . . . . . . . . . . 8
3.5. Structure of OPUCn MSI with Payload type 0x22 . . . . . . 8 3.5. Structure of OPUCn MSI with Payload type 0x22 . . . . . . 8
3.6. Client Signal Mappings . . . . . . . . . . . . . . . . . 8 3.6. Client Signal Mappings . . . . . . . . . . . . . . . . . 8
4. Applicability and GMPLS Implications . . . . . . . . . . . . 10 4. Applicability and GMPLS Implications . . . . . . . . . . . . 10
4.1. Applicability and Challenges . . . . . . . . . . . . . . 10 4.1. Applicability and Challenges . . . . . . . . . . . . . . 10
4.2. GMPLS Implications and Applicability . . . . . . . . . . 12 4.2. GMPLS Implications and Applicability . . . . . . . . . . 12
4.2.1. TE-Link Representation . . . . . . . . . . . . . . . 12 4.2.1. TE-Link Representation . . . . . . . . . . . . . . . 12
4.2.2. Implications and Applicability for GMPLS Signalling . 13 4.2.2. Implications and Applicability for GMPLS Signalling . 13
4.2.3. Implications and Applicability for GMPLS Routing . . 14 4.2.3. Implications and Applicability for GMPLS Routing . . 14
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15
6. Authors (Full List) . . . . . . . . . . . . . . . . . . . . . 15 6. Authors (Full List) . . . . . . . . . . . . . . . . . . . . . 15
7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 16 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 16
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
9. Security Considerations . . . . . . . . . . . . . . . . . . . 17 9. Security Considerations . . . . . . . . . . . . . . . . . . . 17
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 10. Normative References . . . . . . . . . . . . . . . . . . . . 17
10.1. Normative References . . . . . . . . . . . . . . . . . . 17
10.2. Informative References . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction 1. Introduction
The current GMPLS routing [RFC7138] and signaling extensions The current GMPLS routing [RFC7138] and signaling extensions
[RFC7139] only includes coverage for the control of all the OTN [RFC7139] only supports the control of OTN signals and capabilities
capabilities that were defined in the 2012 version of G.709 that were defined in the 2012 version of G.709 [ITU-T_G709_2012].
[ITU-T_G709_2012].
While the 2016 version of G.709 [ITU-T_G709_2016] introduces support Since the publishment of the latest 2016 version of G.709
for new higher rate ODU signals, termed ODUCn (which have a nominal [ITU-T_G709_2016], which introduces support for new higher rate ODU
rate of n x 100 Gbps), how to use GMPLS to configure ODUCn should be signals, termed ODUCn (which have a nominal rate of n x 100 Gbps),
taken into consideration. But it seems how to configure the ODUCn how to applied GMPLS to ODUCn case should be taken into
link needs more discussion, so this draft mainly focuses on the use consideration. As OTUCn and ODUCn only perform section layer role
of current GMPLS mechanisms to set up ODUk/ODUflex over an existing only according to the definition in G.709 [ITU-T_G709_2016], which
ODUCn link. means the OTUCn and ODUCn are only used to provide for the transfer
of information between two adjacent upper layer cross-connects, i.e.,
ODUk/ODUflex cross connects, it's not appropriate to apply GMPLS to
OTUCn and ODUCn. Therefore, this document mainly focuses on the use
of GMPLS mechanisms to set up ODUk/ODUflex over an existing ODUCn
link.
This document presents an overview of the changes introduced in This document first presents an overview of the changes introduced in
[ITU-T_G709_2016] to motivate the present topic and then analyzes how [ITU-T_G709_2016] to motivate the present topic and then analyzes how
the current GMPLS routing and signalling mechanisms can be utilized the current GMPLS routing and signalling mechanisms can be utilized
to setup ODUk/ODUflex connections over ODUCn links. to setup ODUk/ODUflex connections over ODUCn links. In order to make
the description in this document clear, how to set up ODUCn link is
also mentioned.
1.1. Scope 1.1. Scope
For the purposes of the B100G control plane discussion, the OTN For the purposes of the B100G control plane discussion, the OTN
should be considered as a combination of ODU and OTSi layers. Note should be considered as a combination of ODU and OTSi layers. Note
that [ITU-T_G709_2016] is deprecating the use of the term "OCh" for that [ITU-T_G709_2016] is deprecating the use of the term "OCh" for
B100G entities, and leaving it intact only for maintaining continuity B100G entities, and leaving it intact only for maintaining continuity
in the description of the signals with bandwidth upto 100G. This in the description of the signals with bandwidth upto 100G.
document focuses on only the control of the ODU layer. The control
of the OTSi layer is out of scope of this document. But in order to
facilitate the description of the challenges brought by
[ITU-T_G709_2016] to B100G GMPLS routing and signalling, some general
description about OTSi will be included in this draft.
2. Terminology
2.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", This document only focuses on the control of the ODU layer. The
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this control of the OTSi layer is out of scope of this document. But in
document are to be interpreted as described in RFC 2119 [RFC2119]. order to facilitate the description of the challenges brought by
[ITU-T_G709_2016] to B100G GMPLS routing and signalling, some general
description about OTSi is included in section 4 of this document.
2.2. OTN terminology used in this document 2. OTN terminology used in this document
a. OPUCn: Optical Payload Unit -Cn. a. OPUCn: Optical Payload Unit -Cn.
b. ODUCn: Optical Data Unit - Cn. b. ODUCn: Optical Data Unit - Cn.
c. OTUCn: Fully standardized Optical Transport Unit - Cn. c. OTUCn: Fully standardized Optical Transport Unit - Cn.
d. OTUCn-M: This signal is an extension of the OTUCn signal d. OTUCn-M: This signal is an extension of the OTUCn signal
introduced above. This signal contains the same amount of introduced above. This signal contains the same amount of
overhead as the OTUCn signal, but contains a reduced amount of overhead as the OTUCn signal, but contains a reduced amount of
skipping to change at page 4, line 15 skipping to change at page 4, line 9
Multiplex Structrure Indicator (MSI) defined below. Multiplex Structrure Indicator (MSI) defined below.
f. MSI: Multiplex Structure Indicator. This structure indicates the f. MSI: Multiplex Structure Indicator. This structure indicates the
grouping of the tributary slots in an OPU payload area to realize grouping of the tributary slots in an OPU payload area to realize
a client signal that is multiplexed into an OPU. The individual a client signal that is multiplexed into an OPU. The individual
clients multiplexed into the OPU payload area are distinguished clients multiplexed into the OPU payload area are distinguished
by the Tributary Port number (TPN). by the Tributary Port number (TPN).
g. GMP: Generic Mapping Procedure. g. GMP: Generic Mapping Procedure.
h. OTSiG: see [ITU-T_G872] h. OTSiG: The set of OTSi that supports a single digital client.
i. OTSiA: see [ITU-T_G872] i. OTSiA: The OTSiG together with the non-associated overhead
(OTSiG-O).
Detailed description of these terms can be found in Detailed description of these terms can be found in [ITU-T_G709_2016]
[ITU-T_G709_2016]. and [ITU-T_G807].
3. Overview of B100G in G.709 3. Overview of B100G in G.709
This section provides an overview of new features in This section provides an overview of new features in
[ITU-T_G709_2016]. [ITU-T_G709_2016].
3.1. OTUCn 3.1. OTUCn
In order to carry client signals with rates greater than 100Gbps, In order to carry client signals with rates greater than 100Gbps,
[ITU-T_G709_2016] takes a general and scalable approach that [ITU-T_G709_2016] takes a general and scalable approach that
decouples the rates of OTU signals from the client rate evolution. decouples the rates of OTU signals from the client rate. The new OTU
The new OTU signal is called OTUCn; this signal is defined to have a signal is called OTUCn, and this signal is defined to have a rate of
rate of (approximately) n*100G. The following are the key (approximately) n*100G. The following are the key characteristics of
characteristics of the OTUCn signal: the OTUCn signal:
a. The OTUCn signal contains one ODUCn. The OTUCn and ODUCn signals a. The OTUCn signal contains one ODUCn. The OTUCn and ODUCn signals
perform digital section roles only (see perform digital section roles only (see
[ITU-T_G709_2016]:Section 6.1.1) [ITU-T_G709_2016]:Section 6.1.1)
b. The OTUCn signals can be viewed as being formed by interleaving n b. The OTUCn signals can be viewed as being formed by interleaving n
OTUC signals (where are labeled 1, 2, ..., n), each of which has OTUC signals (which are labeled 1, 2, ..., n), each of which has
the format of a standard OTUk signal without the FEC columns (per the format of a standard OTUk signal without the FEC columns (per
[ITU-T_G709_2016]Figure 7-1). The ODUCn have a similar [ITU-T_G709_2016]Figure 7-1). The ODUCn have a similar
structure, i.e. they can be seen as being formed by interleaving structure, i.e. they can be seen as being formed by interleaving
n instances of ODUC signals (respectively). The OTUC signal n instances of ODUC signals (respectively). The OTUC signal
contains the ODUC signals, just as in the case of fixed rate OTUs contains the ODUC signals, just as in the case of fixed rate OTUs
defined in G.709 [ITU-T_G709_2016]. defined in G.709 [ITU-T_G709_2016].
c. Each of the OTUC "slices" have the same overhead (OH) as the c. Each of the OTUC "slices" have the same overhead as the standard
standard OTUk signal in G.709 [ITU-T_G709_2016]. The combined OTUk signal in G.709 [ITU-T_G709_2016]. The combined signal
signal OTUCn has n instances of OTUC OH, ODUC OH. OTUCn has n instances of OTUC overhead, ODUC overhead.
d. The OTUC signal has a slightly higher rate compared to the OTU4 d. The OTUC signal has a slightly higher rate compared to the OTU4
signal (without FEC); this is to ensure that the OPUC payload signal (without FEC); this is to ensure that the OPUC payload
area can carry an ODU4 signal. area can carry an ODU4 signal.
3.1.1. Carrying OTUCn between 3R points
As explained above, within G.709 [ITU-T_G709_2016], the OTUCn, ODUCn As explained above, within G.709 [ITU-T_G709_2016], the OTUCn, ODUCn
and OPUCn signal structures are presented in a (physical) interface and OPUCn signal structures are presented in a (physical) interface
independent manner, by means of n OTUC, ODUC and OPUC instances that independent manner, by means of n OTUC, ODUC and OPUC instances that
are marked #1 to #n. Specifically, the definition of the OTUCn are marked #1 to #n. Specifically, the definition of the OTUCn
signal does not cover aspects such as FEC, modulation formats, etc. signal does not cover aspects such as FEC, modulation formats, etc.
These details are defined as part of the adaptation of the OTUCn These details are defined as part of the adaptation of the OTUCn
layer to the optical layer(s). The specific interleaving of layer to the optical layer(s). The specific interleaving of
OTUC/ODUC/OPUC signals onto the optical signals is interface specific OTUC/ODUC/OPUC signals onto the optical signals is interface specific
and specified for OTN interfaces with standardized application codes and specified for OTN interfaces with standardized application codes
in the interface specific recommendations (G.709.x). in the interface specific recommendations (G.709.x).
The following scenarios of OTUCn transport need to be considered (see OTUCn interfaces can be categorized as follows, based on the type of
Figure 1): peer network element (see Figure 1):
a. inter-domain interfaces: These types of interfaces are used for a. inter-domain interfaces: These types of interfaces are used for
connecting OTN edge nodes to (a) client equipment (e.g. routers) connecting OTN edge nodes to (a) client equipment (e.g. routers)
or (b) hand-off points from other OTN networks. ITU-T has or (b) hand-off points from other OTN networks. ITU-T has
standardized the Flexible OTN (FlexO) interfaces to support these standardized the Flexible OTN (FlexO) interfaces to support these
functions. Recommendation [ITU-T_G709.1] specifies a flexible functions. For example, Recommendation [ITU-T_G709.1] specifies
interoperable short-reach OTN interface over which an OTUCn (n a flexible interoperable short-reach OTN interface over which an
>=1) is transferred, using bonded FlexO interfaces which belong OTUCn (n >=1) is transferred, using bonded FlexO interfaces which
to a FlexO group. In its current form, Recommendation belong to a FlexO group.
[ITU-T_G709.1] is limited to the case of transporting OTUCn
signals using n 100G Ethernet PHY(s). When the PHY(s) for the
emerging set of Ethernet signals, e.g. 200GbE and 400GbE, become
available, new recommendations can define the required
adaptations.
b. intra-domain interfaces: In these cases, the OTUCn is transported b. intra-domain interfaces: In these cases, the OTUCn is transported
using a proprietary (vendor specific) encapsulation, FEC etc. In using a proprietary (vendor specific) encapsulation, FEC etc. It
future, it may be possible to transport OTUCn for intra-domain may also be possible to transport OTUCn for intra-domain links
links using future variants of FlexO. using FlexO.
================================================================== ==================================================================
+--------------------------------------------------------+ +--------------------------------------------------------+
| OTUCn signal | | OTUCn signal |
+--------------------------------------------------------+ +--------------------------------------------------------+
| Inter+Domain | Intra+Domain | Intra+Domain | | Inter+Domain | Intra+Domain | Intra+Domain |
| Interface (IrDI)| Interface (IaDI)| Interface | | Interface (IrDI)| Interface (IaDI)| Interface |
| FlexO (G.709.1) | FlexO (G.709.x) | Proprietary | | FlexO (G.709.1) | FlexO (G.709.x) | Proprietary |
| | (Future) | Encap, FEC etc. | | | (Future) | Encap, FEC etc. |
skipping to change at page 6, line 25 skipping to change at page 6, line 10
================================================================== ==================================================================
Figure 1: OTUCn transport possibilities Figure 1: OTUCn transport possibilities
3.2. ODUCn 3.2. ODUCn
The ODUCn signal [ITU-T_G709_2016] can be viewed as being formed by The ODUCn signal [ITU-T_G709_2016] can be viewed as being formed by
the appropriate interleaving of content from n ODUC signal instances. the appropriate interleaving of content from n ODUC signal instances.
The ODUC frames have the same structure as a standard ODU -- in the The ODUC frames have the same structure as a standard ODU -- in the
sense that it has the same Overhead (OH) area, and the payload area sense that it has the same Overhead area, and the payload area -- but
-- but has a higher rate since its payload area can embed an ODU4 has a higher rate since its payload area can embed an ODU4 signal.
signal.
The ODUCn signals have a rate that is captured in Table 1. The ODUCn signals have a rate that is captured in Table 1.
+----------+--------------------------------------------------------+ +----------+--------------------------------------------------------+
| ODU Type | ODU Bit Rate | | ODU Type | ODU Bit Rate |
+----------+--------------------------------------------------------+ +----------+--------------------------------------------------------+
| ODUCn | n x 239/226 x 99,532,800 kbit/s = n x 105,258,138.053 | | ODUCn | n x 239/226 x 99,532,800 kbit/s = n x 105,258,138.053 |
| | kbit/s | | | kbit/s |
+----------+--------------------------------------------------------+ +----------+--------------------------------------------------------+
Table 1: ODUCn rates Table 1: ODUCn rates
The ODUCn is a multiplex section ODU signal, and is mapped into an The ODUCn is a multiplex section ODU signal, and is mapped into an
OTUCn signal which provides the regenerator section layer. In some OTUCn signal which provides the regenerator section layer. In some
scenarios, the ODUCn, and OTUCn signals will be co-terminous, i.e. scenarios, the ODUCn, and OTUCn signals will be co-terminated, i.e.
they will have identical source/sink locations. [ITU-T_G709_2016] they will have identical source/sink locations. [ITU-T_G709_2016]
and [ITU-T_G872] allow for the ODUCn signal to pass through a digital and [ITU-T_G872] allow for the ODUCn signal to pass through a digital
regenerator node which will terminate the OTUCn layer, but will pass regenerator node which will terminate the OTUCn layer, but will pass
the regenerated (but otherwise untouched) ODUCn towards a different the regenerated (but otherwise untouched) ODUCn towards a different
OTUCn interface where a fresh OTUCn layer will be initiated (see OTUCn interface where a fresh OTUCn layer will be initiated (see
Figure 2). In this case, the ODUCn is carried by 3 OTUCn segments. Figure 2). In this case, the ODUCn is carried by 3 OTUCn segments.
Specifically, the OPUCn signal flows through these regenerators Specifically, the OPUCn signal flows through these regenerators
unchanged. That is, the set of client signals, their TPNs, trib-slot unchanged. That is, the set of client signals, their TPNs, trib-slot
allocation remains unchanged. Note however that the ODUCn Overhead allocation remains unchanged. The ODUCn Overhead might be modified
(OH) might be modified if TCM sub-layers are instantiated in order to if TCM sub-layers are instantiated in order to monitor the
monitor the performance of the repeater hops. In this sense, the performance of the regenerator hops. In this sense, the ODUCn should
ODUCn should not be seen as a general ODU which can be switched via NOT be seen as a general ODU which can be switched via an ODUk cross-
an ODUk cross-connect. connect.
================================================================== ==================================================================
+--------+ +--------+ +--------+ +--------+ +--------+ +--------+
| +-----------+ | | +----------+ | | +-----------+ |
| OTN |-----------| OTN | | OTN |----------| OTN | | OTN |-----------| OTN |
| DXC +-----------+ WXC +----------------+ WXC +----------+ DXC | | DXC +-----------+ DXC +
| | | 3R | | 3R | | | | | | |
+--------+ +--------+ +--------+ +--------+ +--------+ +--------+
<--------------------------------ODUCn------------------------------> <--------ODUCn------->
<------------------> <-----------------------> <------------------> <-------OTUCn------>
OTUCn OTUCn OTUCn
+--------+ +--------+ +--------+ +--------+
| +--------+ | | +----------+ |
| OTN |--------| OTN | | OTN |----------| OTN |
| DXC +--------+ WXC +--------+ WXC +----------+ DXC |
| | | 3R | | 3R | | |
+--------+ +--------+ +--------+ +--------+
<-------------------------ODUCn-------------------------->
<---------------> <---------------> <------------------>
OTUCn OTUCn OTUCn
================================================================== ==================================================================
Figure 2: ODUCn signal Figure 2: ODUCn signal
3.3. OTUCn-M 3.3. OTUCn-M
The standard OTUCn signal has the same rate as that of the ODUCn The standard OTUCn signal has the same rate as that of the ODUCn
signal as captured in Table 1. This implies that the OTUCn signal signal as captured in Table 1. This implies that the OTUCn signal
can only be transported over wavelength groups which have a total can only be transported over wavelength groups which have a total
capacity of multiples of (approximately) 100G. Modern DSPs support a capacity of multiples of (approximately) 100G. Modern DSPs support a
variety of bit rates per wavelength, depending on the reach variety of bit rates per wavelength, depending on the reach
requirements for the optical link. In other words, it is possible to requirements for the optical link. In other words, it is possible to
extend the reach of an optical link (i.e. increase the physical extend the reach of an optical link (i.e. increase the physical
distance covered) by lowering the bitrate of the client signal that distance covered) by lowering the bitrate of the client signal that
is modulated onto the carrier(s). By the very nature of the OTUCn is modulated onto the optical signals. By the very nature of the
signal, it is constrained to rates which are multiples of OTUCn signal, it is constrained to rates which are multiples of
(approximately) 100G. If it so happens that the total rate of the (approximately) 100G. If it happens that the total rate of the LO-
LO-ODUs carried over the ODUCn is smaller than n X 100G, it is ODUs carried over the ODUCn is smaller than n X 100G, it is possible
possible to "crunch" the OTUCn to remove the unused capacity. With to "crunch" the OTUCn to remove the unused capacity. With this in
this in mind, ITU-T supports the notion of a reduced rate OTUCn mind, ITU-T supports the notion of a reduced rate OTUCn signal,
signal, termed the OTUCn-M. The OTUCn-M signal is derived from the termed the OTUCn-M. The OTUCn-M signal is derived from the OTUCn
OTUCn signal by retaining all the n instances of overhead (one per signal by retaining all the n instances of overhead (one per OTUC
OTUC slice) but only M tributary slots of capacity. slice) but only M tributary slots of capacity.
3.4. Time Slot Granularity 3.4. Time Slot Granularity
[ITU-T_G709_2012] introduced the support for 1.25G granular tributary [ITU-T_G709_2012] introduced the support for 1.25G granular tributary
slots in OPU2, OPU3, and OPU4 signals. With the introduction of slots in OPU2, OPU3, and OPU4 signals. With the introduction of
higher rate signals, it is no longer practical for the optical higher rate signals, it is not practical for the optical networks
networks (and the datapath hardware) to support a very large number (and the data plane hardware) to support a very large number of
of flows at such a fine granularity. ITU-T has defined the OPUC with connections at such a fine granularity. ITU-T has defined the OPUC
a tributary slot granularity of 5G. This means that the ODUCn signal with a tributary slot granularity of 5G. This means that the ODUCn
has 20*n tributary slots (of 5Gbps capacity). It is worthwhile signal has 20*n tributary slots (of 5Gbps capacity). It is
considering that the range of tributary port number (TPN) is 10*n, worthwhile considering that the range of tributary port number (TPN)
and not 20*n which would allow for a different client signal to be is 10*n instead of 20*n, which restricts the maximum client signals
carried in each TS. As an example, it will not be possible to embed that could be carried over one single ODUC1.
15 5G ODUflex signals in a ODUC1.
3.5. Structure of OPUCn MSI with Payload type 0x22 3.5. Structure of OPUCn MSI with Payload type 0x22
As mentioned above, the OPUCn signal has 20*n 5G tributary slots. As mentioned above, the OPUCn signal has 20*n 5G tributary slots.
The OPUCn contains n PSI structures, one per OPUC instance. The PSI The OPUCn contains n PSI structures, one per OPUC instance. The PSI
structure consists of the Payload Type (of 0x22), followed by a structure consists of the Payload Type (of 0x22), followed by a
Reserved Field (1 byte), followed by the MSI. The OPUCn MSI field Reserved Field (1 byte) and the MSI. The OPUCn MSI field has a fixed
has a fixed length of 40*n bytes and indicates the availability of length of 40*n bytes and indicates the availability of each TS. Two
each TS. Two bytes are used for each of the 20*n tributary slots, bytes are used for each of the 20*n tributary slots, and each such
and each such information structure has the following format information structure has the following format ([ITU-T_G709_2016]
([ITU-T_G709_2016] G.709:Section 20.4.1): G.709:Section 20.4.1):
a. The TS availability bit 1 indicates if the tributary slot is a. The TS availability bit indicates if the tributary slot is
available or unavailable available or unavailable
b. The TS occupation bit 9 indicates if the tributary slot is b. The TS occupation bit indicates if the tributary slot is
allocated or unallocated allocated or unallocated
c. b.c. The tributary port # in bits 2 to 8 and 10 to 16 indicates c. The tributary port bits indicates the port number of the client
the port number of the client that is being carried in this signal that is being carried in this specific TS. A flexible
specific TS; a flexible assignment of tributary port to tributary assignment of tributary port to tributary slots is possible.
slots is possible. Numbering of tributary ports are is from 1 to Numbering of tributary ports is from 1 to 10n.
10n.
3.6. Client Signal Mappings 3.6. Client Signal Mappings
The approach taken by the ITU-T to map non-OTN client signals to the The approach taken by the ITU-T to map non-OTN client signals to the
appropriate ODU containers is as follows: appropriate ODU containers is as follows:
a. All client signals with rates less than 100G are mapped as a. All client signals with rates less than 100G are mapped into ODU
specified in [ITU-T_G709_2016]:Clause 17. These mappings are container as specified in clause 17 of [ITU-T_G709_2016]. These
identical to those specified in the earlier revision of G.709 mappings are identical to those specified in the earlier revision
[ITU-T_G709_2012]. Thus, for example, the 1000BASE-X/10GBASE-R of G.709 [ITU-T_G709_2012]. For example, the 1000BASE-
signals are mapped to ODU0/ODU2e respectively (see Table 2 -- X/10GBASE-R signals are mapped to ODU0/ODU2e respectively (see
based on Table 7-2 in [ITU-T_G709_2016]) Table 2 -- based on Table 7-2 in [ITU-T_G709_2016])
b. Always map the new and emerging client signals to ODUflex signals b. New emerging client signals are usually mapped into ODUflex
of the appropriate rates (see Table 2 -- based on Table 7-2 in signals of the appropriate rates (see Table 2 according to the
[ITU-T_G709_2016]) Table 7-2 in [ITU-T_G709_2016])
c. Drop support for ODU Virtual Concatenation. This simplifies the c. ODU Virtual Concatenation is not supported any more. This
network, and the supporting hardware since multiple different simplifies the network, and the supporting hardware since
mappings for the same client are no longer necessary. Note that multiple different mappings for the same client are no longer
legacy implementations that transported sub-100G clients using necessary. Note that legacy implementations that transported
ODU VCAT shall continue to be supported. sub-100G clients using ODU VCAT shall continue to be supported.
d. ODUflex signals are low-order signals only. If the ODUflex d. ODUflex signals are low-order signals only. If the ODUflex
entities have rates of 100G or less, they can be transported entities have rates of 100G or less, they can be transported over
using either an ODUk (k=1..4) or an ODUCn server layer. On the either an ODUk (k=1..4) or an ODUCn. For ODUflex connections
other hand, ODUflex connections with rates greater than 100G will with rates greater than 100G, ODUCn is required.
require the server layer to be ODUCn. The ODUCn signals must be
adapted to an OTUCn signal. Figure 3 illstrates the hierarchy of
the digital signals defined in [ITU-T_G709_2016].
+----------------+--------------------------------------------------+ +----------------+--------------------------------------------------+
| ODU Type | ODU Bit Rate | | ODU Type | ODU Bit Rate |
+----------------+--------------------------------------------------+ +----------------+--------------------------------------------------+
| ODU0 | 1,244,160 Kbps | | ODU0 | 1,244,160 Kbps |
| ODU1 | 239/238 x 2,488,320 Kbps | | ODU1 | 239/238 x 2,488,320 Kbps |
| ODU2 | 239/237 x 9,953,280 Kbps | | ODU2 | 239/237 x 9,953,280 Kbps |
| ODU2e | 239/237 x 10,312,500 Kbps | | ODU2e | 239/237 x 10,312,500 Kbps |
| ODU3 | 239/236 x 39,813,120 Kbps | | ODU3 | 239/236 x 39,813,120 Kbps |
| ODU4 | 239/227 x 99,532,800 Kbps | | ODU4 | 239/227 x 99,532,800 Kbps |
skipping to change at page 10, line 34 skipping to change at page 10, line 34
+------------+ +------------+
================================================================== ==================================================================
Figure 3: Digital Structure of OTN interfaces (from G.709:Figure 6-1) Figure 3: Digital Structure of OTN interfaces (from G.709:Figure 6-1)
4. Applicability and GMPLS Implications 4. Applicability and GMPLS Implications
4.1. Applicability and Challenges 4.1. Applicability and Challenges
Two typical scenarios are depicted in Appendix XIII of This section analyzes the OTUCn deployment scenarios to identify
[ITU-T_G709_2016], which are also introduced into this document to potential extensions to GMPLS that would be needed. When OTUCn links
help analyze the potential extension to GMPLS needed. Though these are established between line ports of two different network elements,
two scenarios are mainly introduced in G.709 to describe OTUCn sub two scenarios are possible. These scenarios are modeled according to
rates application, they can also be used to describe general OTUCn those illustrated in Appendix XIII of [ITU-T_G709_2016]. Note that
application. One thing that should be note is these two scenarios while this Appendix illustrates OTUCn subrating possibilities, the
are a little different from those described in [ITU-T_G709_2016], as scenarios serve a more general purpose also. Two possible
the figure in this section include the OTSi(G) in to facilitate the realization of OTUCn realizations between nodes are:
description of the challenge brought by [ITU-T_G709_2016].
The first scenarios is depicted in Figure 4. This scenario deploys
OTUCn/OTUCn-M between two line ports connecting two L1/L0 ODU cross
connects (XC) within one optical transport network. One OTUCn is
actually carried by one OTSi(G) or OTSiA.
As defined in [ITU-T_G872], OTSiG is used to represent one or more
OTSi as a group to carry a single client signal (e.g., OTUCn). The
OTSiG may have non-associated overhead, the combination of the OTSiG
and OTSiG-O is represented by the OTSiA management/control
abstraction.
In this scenario, it is clear that the OTUCn and ODUCn link can be a. The first scenario (see Figure 4) deploys OTUCn/OTUCn-M between
automatically established, after/together with the setup of OTSi(G) two line ports connecting two L1/L0 ODU cross connects (XC)
or OTSiA, as both OTUCn and ODUCn perform section layer only. One within one optical transport network. As defined in
client OTUCn signal is carried by one single huge OTSi signal or a [ITU-T_G807], the OTUCn/OTUCn-M signal is transported using by
group of OTSi. There is a 1:1 mapping relationship between OTUCn and one OTSiG, which could be comprised of one or more OTSi. The
OTSi(G) or OTSiA. OTSiG may have non-associated overhead (denoted as OTSiG-O); the
combination of the OTSiG and OTSiG-O is represented by the OTSiA
management/control abstraction. There is a 1:1 mapping
relationship between OTUCn and OTSiG or OTSiA. For example, a
400G OTUC4 signal can be carried over a single OTSi signal with a
400G capcity, or perhaps split into 4 100G digital information
streams each of which is carried over a OTSi signal with a 100G
capacity. In this scenario, it is clear that the OTUCn and ODUCn
link can be automatically established, after/together with the
setup of OTSiG or OTSiA, as both OTUCn and ODUCn perform section
layer only. Once the ODUCn link is automatically established, it
can be advertized as a TE-link and used for setting up ODUk/
ODUflex connections.
For example, one 400G OTUCn signal can be carried by one single 400G b. The second scenario (see depicted in Figure 5) deploys OTUCn/
OTSi signal or one 400G OTUCn signal can be split into 4 different OTUCn-M between transponders which are in a different domain B,
OTUC instances, with each instances carried by one OTSi. Those four and are separated from the L1 ODU XCs in domain A and/or C. In
OTSi function as a group to carry a single 400G OTUCn signal. this scenario, the end-to-end ODUCn is actually supported by
three different OTUCn or OTUCn-M segments, which are in turn
carried by their respective OTSi(G) or OTSiA. In this example,
the OTUCn links will be established automatically after/together
with the setup of OTSi(G) or OTSiA. Note that until both
transponder nodes in domain B have been configured, the ODUCn
signal transmitted by node A doesn't reach node C. Until all the
required configuration operations are completed, the ODUCn.STAT
field will reflect the AIS (i.e. error) status. Once all the
provisioning has been performed in domain B, and the links
connecting the edge nodes to transponders in domain B are error
free, the end to end ODUCn flows will be established. In this
case, the receipt of a normal value for the ODUCn.STAT field can
trigger the creation of the ODUCn link.
================================================================== ==================================================================
+--------+ +--------+ +--------+ +--------+
| +---------------------+ | | +---------------------+ |
| OTN |---------------------| OTN | | OTN |---------------------| OTN |
| XC +---------------------+ XC | | XC +---------------------+ XC |
| | | | | | | |
+--------+ +--------+ +--------+ +--------+
<---------- ODUk/ODUflex -----------> <---------- ODUk/ODUflex ----------->
<------------ ODUCn --------------> <------------ ODUCn -------------->
<------- OTUCn/OTUCn-M ---------> <------- OTUCn/OTUCn-M --------->
<--------OTSi(G)/OTSiA---------> <--------OTSi(G)/OTSiA--------->
================================================================== ==================================================================
Figure 4: Scenario A Figure 4: Scenario A
The second scenarios is depicted in Figure 4. This scenario deploys
OTUCn/OTUCn-M between transponders which are in a different domain B,
which are separated from the L1 ODU XCs in domain A and/or C. one
end-to-end ODUCn is actually supported by three different OTUCn or
OTUCn-M segments, which are in turn carried by OTSi(G) or OTSiA.
In the second scenario, OTUCn links will be established automatically
after/together with the setup of OTSi(G) or OTSiA, while there are
still some doubts about how the ODUCn link is established. In
principle, it could/should be possible but it is not yet clear in
details how the ODUCn link can be automatically setup.
================================================================== ==================================================================
+--------------------------------------+ +----------------------------+
A | B | A or C A | B | A or C
| | | | | | | |
+--------+ | +--------+ +--------+ | +--------+ +--------+ | +--------+ +--------+ | +--------+
| +----------|-+ | | +-|--------+ | | +----------|-+ | | +-|--------+ |
| OTN |----------|-| Transp | | Transp |-|--------| OTN | | OTN |----------|-| Transp | | Transp |-|--------| OTN |
| XC +----------|-+ onder +----------------+ onder +-|--------+ XC | | XC +----------|-+ onder +------+ onder +-|--------+ XC |
| | | | | | | | | | | | | | | | | | | |
+--------+ | +--------+ +--------+ | +--------+ +--------+ | +--------+ +--------+ | +--------+
| | | |
+--------------------------------------+ +----------------------------+
<-----------------------------ODUk/ODUflex----------------------------> <------------------------ODUk/ODUflex----------------------->
<----------------------------- ODUCn -------------------------------> <------------------------ ODUCn -------------------------->
<-------OTUCn-------><-----OTUCn/OTUCn-M-----><-------OTUCn-------> <------OTUCn------><---OTUCn/OTUCn-M---><------OTUCn------>
<--OTSi(G)/OTSiA--> <----OTSi(G)/OTSiA----> <--OTSi(G)/OTSiA--> <-OTSi(G)/OTSiA-> <--OTSi(G)/OTSiA--> <-OTSi(G)/OTSiA->
================================================================== ==================================================================
Figure 5: Scenario B Figure 5: Scenario B
According to the above description, it can be concluded that some
uncertainty about setup of ODUCn link still exist, and this
uncertainty may have relationship with the progress in ITU-T. Based
on the analysis, it is suggested that the scope of this draft should
mainly focus on how to set up ODUk/ODUflex LSPs over ODUCn links, as
also indicated in the figure above.
4.2. GMPLS Implications and Applicability 4.2. GMPLS Implications and Applicability
4.2.1. TE-Link Representation 4.2.1. TE-Link Representation
Section 3 of RFC7138 describes how to represent G.709 OTUk/ODUk with Section 3 of RFC7138 describes how to represent G.709 OTUk/ODUk with
TE-Links in GMPLS. Similar to that, ODUCn links can also be TE-Links in GMPLS. Similar to that, ODUCn links can also be
represented as TE-Links, which can be seen in the figure below. represented as TE-Links, which can be seen in the figure below.
================================================================== ==================================================================
3R 3R +-----+ +-----+
+--------+ +--------+ +--------+ +--------+ | | | |
| | | | | | | | | A |<-OTUCn Link->| B |
| node A |<-OTUCn Link->| node B |<-OTUCn Link->| node C |<-OTUCn Link->| node D | | | | |
| | | | | | | | +-----+ +-----+
+--------+ +--------+ +--------+ +--------+ |<--- ODUCn Link -->|
|<--------------------------- ODUCn Link -------------------------->| |<---- TE-Link ---->|
|<----------------------------- TE-Link --------------------------->|
3R 3R
+-----+ +-----+ +-----+ +-----+
| | | | | | | |
| A |<-OTUCn Link->| B |<-OTUCn Link->| C |<-OTUCn Link->| D |
| | | | | | | |
+-----+ +-----+ +-----+ +-----+
|<----------------------- ODUCn Link ------------------------>|
|<------------------------ TE-Link -------------------------->|
================================================================== ==================================================================
Figure 6: telink Figure 6: ODUCn TE-Links
Two ends of a TE-Link is able to know whether the TE-Link is Two endpoints of a TE-Link are configured with the supported resource
supported by an ODUCn or an ODUk or an OTUk, as well as the resource information, which may include whether the TE-Link is supported by an
related information (e.g., slot granularity, number of tributary slot ODUCn or an ODUk or an OTUk, as well as the link attribute
information (e.g., slot granularity, number of tributary slot
available). available).
4.2.2. Implications and Applicability for GMPLS Signalling 4.2.2. Implications and Applicability for GMPLS Signalling
Once the ODUCn link is configured, the GMPLS mechanisms defined in Once the ODUCn link is configured, the GMPLS mechanisms defined in
RFC7139 can be reused to set up ODUk/ODUflex LSP with no/few changes. RFC7139 can be reused to set up ODUk/ODUflex LSP with no/few changes.
As the resource on the ODUCn link which can be seen by the client As the resource on the ODUCn link which can be seen by the client
ODUk/ODUflex is a serial of 5G slots, the label defined in RFC7139 is ODUk/ODUflex is a set of 5G slots, the label defined in RFC7139 is
able to accommodate the requirement of the setup of ODUk/ODUflex over able to accommodate the requirement of the setup of ODUk/ODUflex over
ODUCn link. The OTN-TDM GENERALIZED_LABEL object is used to indicate ODUCn link. In [RFC7139], the OTN-TDM GENERALIZED_LABEL object is
how the LO ODUj signal is multiplexed into the HO ODUk link. The LO used to indicate how the LO ODUj signal is multiplexed into the HO
ODUj Signal Type is indicated by Traffic Parameters, while the type ODUk link. In a similar manner, the OTN-TDM GENERALIZED_LABEL object
of HO ODUk link is identified by the selected interface carried in is used to indicate how the ODUk signal is multiplexed into the ODUCn
the IF_ID RSVP_HOP object. IF_ID RSVP_HOP object provides a pointer link. The ODUk Signal Type is indicated by Traffic Parameters. The
to the interface associated with TE-Link and therefore the two nodes IF_ID RSVP_HOP object provides a pointer to the interface associated
terminating the TE-link know (by internal/local configuration) the with TE-Link and therefore the two nodes terminating the TE-link know
attributes of ODUCn TE-Link. (by internal/local configuration) the attributes of the ODUCn TE
Link.
One thing should be note is the TPN used in RFC7139 and defined in One thing should be note is the TPN used in RFC7139 and defined in
G.709-2016 for ODUCn link. Since the TPN currently defined in G.709 G.709-2016 for ODUCn link. Since the TPN currently defined in G.709
for ODUCn link has 14 bits, while this field in RFC7139 only has 12 for ODUCn link has 14 bits, while this field in RFC7139 only has 12
bits, some extension work is needed, but this is not so urgent since bits, some extension work is needed, but this is not so urgent since
for today networks scenarios 12 bits are enough, as it can support a for today networks scenarios 12 bits are enough, as it can support a
single ODUCn link up to n=400, namely 40Tbit. single ODUCn link up to n=400, namely 40Tbit.
An example is given below to illustrate the label format defined in An example is given below to illustrate the label format defined in
RFC7139 for multiplexing ODU4 onto ODUC10. One ODUC10 has 200 5G RFC7139 for multiplexing ODU4 onto ODUC10. One ODUC10 has 200 5G
skipping to change at page 14, line 35 skipping to change at page 14, line 46
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 0| Padding Bits(0) | |0 0 0 0 0 0 0 0| Padding Bits(0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
================================================================== ==================================================================
Figure 7: Label format Figure 7: Label format
4.2.3. Implications and Applicability for GMPLS Routing 4.2.3. Implications and Applicability for GMPLS Routing
For routing, we think that no extension to current mechanisms defined For routing, it is deemed that no extension to current mechanisms
in RFC7138 are needed. Because, once one ODUCn link is up, we need defined in RFC7138 are needed. Because, once an ODUCn link is up,
to advertise only the resources that can be used on this ODUCn link the resources that need to be advertised are the resources that
and the multiplexing hierarchy on this link. Considering ODUCn link exposed by this ODUCn link and the multiplexing hierarchy on this
is already configured, it's the ultimate hierarchy of this link. Since the ODUCn link is the ultimate hierarchy of the ODU
multiplexing, there is no need to explicitly extent the ODUCn signal multiplexing, there is no need to explicitly define a new value to
type in the routing. represent the ODUCn signal type in the OSPF-TE routing protocol.
The OSPF-TE extension defined in section 4 of RFC7138 can be used to The OSPF-TE extension defined in section 4 of RFC7138 can be reused
advertise the resource information on the ODUCn link to direct the to advertise the resource information on the ODUCn link to help
setup of ODUk/ODUflex. finish the setup of ODUk/ODUflex.
5. Acknowledgements 5. Acknowledgements
6. Authors (Full List) 6. Authors (Full List)
Qilei Wang (editor) Qilei Wang (editor)
ZTE ZTE
Nanjing, China Nanjing, China
skipping to change at page 17, line 9 skipping to change at page 17, line 16
Akshaya Nadahalli, Individual, nadahalli@gmail.com Akshaya Nadahalli, Individual, nadahalli@gmail.com
8. IANA Considerations 8. IANA Considerations
This memo includes no request to IANA. This memo includes no request to IANA.
9. Security Considerations 9. Security Considerations
None. None.
10. References 10. Normative References
10.1. Normative References
[ITU-T_G709.1] [ITU-T_G709.1]
ITU-T, "ITU-T G.709.1: Flexible OTN short-reach interface; ITU-T, "ITU-T G.709.1: Flexible OTN short-reach interface;
2016", , 2016. 2016", , 2016.
[ITU-T_G709_2012] [ITU-T_G709_2012]
ITU-T, "ITU-T G.709: Optical Transport Network Interfaces; ITU-T, "ITU-T G.709: Optical Transport Network Interfaces;
02/2012", http://www.itu.int/rec/T-REC- 02/2012", http://www.itu.int/rec/T-REC-
G..709-201202-S/en, February 2012. G..709-201202-S/en, February 2012.
[ITU-T_G709_2016] [ITU-T_G709_2016]
ITU-T, "ITU-T G.709: Optical Transport Network Interfaces; ITU-T, "ITU-T G.709: Optical Transport Network Interfaces;
07/2016", http://www.itu.int/rec/T-REC- 07/2016", http://www.itu.int/rec/T-REC-
G..709-201606-P/en, July 2016. G..709-201606-P/en, July 2016.
[ITU-T_G807]
ITU-T, "ITU-T G.807: Generic functional architecture of
the optical media network;
2020", http://www.itu.int/rec/T-REC-G.872/en, February
2020.
[ITU-T_G872] [ITU-T_G872]
ITU-T, "ITU-T G.872: The Architecture of Optical Transport ITU-T, "ITU-T G.872: The Architecture of Optical Transport
Networks; 2017", http://www.itu.int/rec/T-REC-G.872/en, Networks; 2017", http://www.itu.int/rec/T-REC-G.872/en,
January 2017. January 2017.
[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>.
[RFC4328] Papadimitriou, D., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Extensions for G.709 Optical
Transport Networks Control", RFC 4328,
DOI 10.17487/RFC4328, January 2006,
<https://www.rfc-editor.org/info/rfc4328>.
[RFC7138] Ceccarelli, D., Ed., Zhang, F., Belotti, S., Rao, R., and [RFC7138] Ceccarelli, D., Ed., Zhang, F., Belotti, S., Rao, R., and
J. Drake, "Traffic Engineering Extensions to OSPF for J. Drake, "Traffic Engineering Extensions to OSPF for
GMPLS Control of Evolving G.709 Optical Transport GMPLS Control of Evolving G.709 Optical Transport
Networks", RFC 7138, DOI 10.17487/RFC7138, March 2014, Networks", RFC 7138, DOI 10.17487/RFC7138, March 2014,
<https://www.rfc-editor.org/info/rfc7138>. <https://www.rfc-editor.org/info/rfc7138>.
[RFC7139] Zhang, F., Ed., Zhang, G., Belotti, S., Ceccarelli, D., [RFC7139] Zhang, F., Ed., Zhang, G., Belotti, S., Ceccarelli, D.,
and K. Pithewan, "GMPLS Signaling Extensions for Control and K. Pithewan, "GMPLS Signaling Extensions for Control
of Evolving G.709 Optical Transport Networks", RFC 7139, of Evolving G.709 Optical Transport Networks", RFC 7139,
DOI 10.17487/RFC7139, March 2014, DOI 10.17487/RFC7139, March 2014,
<https://www.rfc-editor.org/info/rfc7139>. <https://www.rfc-editor.org/info/rfc7139>.
10.2. Informative References [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
[I-D.izh-ccamp-flexe-fwk] May 2017, <https://www.rfc-editor.org/info/rfc8174>.
Hussain, I., Valiveti, R., Pithewan, K., Wang, Q.,
Andersson, L., Zhang, F., Chen, M., Dong, J., Du, Z.,
zhenghaomian@huawei.com, z., Zhang, X., Huang, J., and Q.
Zhong, "GMPLS Routing and Signaling Framework for Flexible
Ethernet (FlexE)", draft-izh-ccamp-flexe-fwk-00 (work in
progress), October 2016.
Authors' Addresses Authors' Addresses
Qilei Wang (editor) Qilei Wang (editor)
ZTE ZTE Corporation
Nanjing Nanjing
CN CN
Email: wang.qilei@zte.com.cn Email: wang.qilei@zte.com.cn
Radha Valiveti (editor) Radha Valiveti (editor)
Infinera Corp Infinera Corp
Sunnyvale Sunnyvale
USA USA
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