Internet DRAFT - draft-peng-pce-te-constraints
draft-peng-pce-te-constraints
PCE S. Peng
Internet-Draft Q. Xiong
Intended status: Standards Track ZTE Corporation
Expires: January 12, 2022 F. Qin
China Mobile
M. Koldychev
Cisco Systems
S. Sivabalan
Ciena Corporation
July 11, 2021
PCE TE Constraints
draft-peng-pce-te-constraints-06
Abstract
This document proposes a set of extensions for PCEP to support the TE
constraints during path computation, e.g, IGP instance, virtual
network, Slice-id, specific application, color template and FA-id
etc.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on January 12, 2022.
Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 3
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
3. PCEP Extensions for TE Constraints . . . . . . . . . . . . . 3
3.1. Source Protocol TLV . . . . . . . . . . . . . . . . . . . 3
3.2. Multi-topology TLV . . . . . . . . . . . . . . . . . . . 4
3.3. Slice-id TLV . . . . . . . . . . . . . . . . . . . . . . 5
3.4. Application Specific TLV . . . . . . . . . . . . . . . . 6
3.5. Color TLV . . . . . . . . . . . . . . . . . . . . . . . . 7
3.6. FA-id TLV . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Security Considerations . . . . . . . . . . . . . . . . . . . 10
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
7. Normative References . . . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
[RFC5440] describes the Path Computation Element Protocol (PCEP)
which is used between a Path Computation Element (PCE) and a Path
Computation Client (PCC) (or other PCE) to enable computation of
Multi-protocol Label Switching (MPLS) for Traffic Engineering Label
Switched Path (TE LSP). PCEP Extensions for the Stateful PCE Model
[RFC8231] describes a set of extensions to PCEP to enable active
control of MPLS-TE and Generalized MPLS (GMPLS) tunnels. As depicted
in [RFC4655], a PCE MUST be able to compute the path of a TE LSP by
operating on the TED and considering bandwidth and other constraints
applicable to the TE LSP service request. The constraint parameters
are provided such as metric, bandwidth, delay, affinity, etc.
However these parameters can't meet the network slicing requirements.
A PCE always perform path computation based on the network topology
information collected through BGP-LS [RFC7752]. BGP-LS can get
multiple link-state data from multiple IGP instance, or multiple
virtual topologies from a single IGP instance. It is necessary to
restrict the PCE to a small topology scope during path computation
for some special purpose. BGP-LS can also get application specific
TE attributes for a link, it is also necessary to restrict PCE to use
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TE attributes of specific application. The PCE MUST take the
identifier of slicing into consideration during path computation.
This document proposes a set of extensions for PCEP to support the TE
constraints during path computation, e.g, IGP instance, virtual
network, Slice-id, specific application, color template and FA-id
etc.
2. Conventions used in this document
2.1. Terminology
The terminology is defined as [RFC5440] and [RFC7752].
2.2. Requirements Language
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. PCEP Extensions for TE Constraints
As defined in [RFC5440] , the LSPA object is used to specify the LSP
attributes to be taken into account by the PCE during path
computation such as TE constraints. This document proposes several
new TLVs for the LSPA object to carry TE constraints in Network
Slicing.
3.1. Source Protocol TLV
The Source Protocol TLV is optional and is defined to carry the
source protocol constraint.
In a PCReq/PCRpt message, a PCC MAY insert one or more Source
Protocol TLVs to indicate the source protocol that MUST be considered
by the PCE. If more than one Source Protocol TLVs are carried, the
PCE may perform path computation based on the sub-topology identified
by the one of the source protocols. The absence of the Source
Protocol TLV MUST be interpreted by the PCE as a path computation
request for which no constraints need be applied to any of the source
protocols.
In a PCRep/PCInit/PCUpd message, the Source Protocol TLV MAY be
carried so as to provide the source protocol information for the
computed path.
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The format of the Source Protocol TLV is shown as Figure 1:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=TBD1 | Length=12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol-ID | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier |
| (64 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Source Protocol TLV
The code point for the TLV type is TBD1. The TLV length is 12
octets.
Protocol-ID (8 bits): defined in [RFC7752] section 3.2.
Reserved (24 bits): This field MUST be set to zero on transmission
and MUST be ignored on receipt.
Identifier (64 bits): defined in [RFC7752] section 3.2.
3.2. Multi-topology TLV
The Multi-topology TLV is optional and is defined to carry the multi-
topology protocol constraint.
In a PCReq message, a PCC MAY insert one Multi-topology TLV to
indicate the sub-topology of an IGP instance that MUST be considered
by the PCE. The PCE will perform path computation based on the sub-
topology identified by the specific Multi-Topology ID within a source
protocol. The absence of the Multi-topology TLV MUST be interpreted
by the PCE as a path computation request for which no constraints
need be applied to any of the multi-topologies.
In a PCRep/PCInit/PCUpd message, the Multi-topology TLV MAY be
carried so as to provide the Multi-topology information for the
computed path.
The Multi-topology TLV MUST be carried after a Source Protocol TLV,
if not it MUST be ignored.
The format of the Multi-topology TLV is shown as Figure 2:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=TBD2 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|R R R R| Multi-Topology ID | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Multi-topology TLV
The code point for the TLV type is TBD2. The TLV length is 4 octets.
Multi-Topology ID (12 bits): Semantics of the IS-IS MT-ID are defined
in Section 7.2 of [RFC5120]. Semantics of the OSPF MT-ID are defined
in Section 3.7 of [RFC4915]. If the value is derived from OSPF, then
the upper 9 bits MUST be set to 0. Bits R are reserved and SHOULD be
set to 0 when originated and ignored on receipt.
Reserved (16 bits): This field MUST be set to zero on transmission
and MUST be ignored on receipt.
3.3. Slice-id TLV
PCEP message needs to carry Slice ID to let the scope of path
calculation to be limited in a specific slice.
There are many control plane technologies to realize slicing. Some
control plane technologies may directly maintain resources per slice
granularity in the link-state database, only for the case with small
slice scalability. [I-D.bestbar-teas-ns-packet] proposes a more
scalable slicing scheme. The resource information in link-state
database is identified by SA-ID to distinguish the logical topologies
corresponding to different slice-aggregate. Within the controller, a
slice-aggregate includes one or more slices mapped to it. If the
number of slices is small, the resources per slice granularity can be
maintained directly in the link-state database. In this case,
different slice may be mapped to different slice-aggregate. If the
number of slices is large, it is not recommended to maintain the
slice granularity resources in the link-state database, but the
aggregated SA-ID granularity.
In any case, the slice service (such as VPN service) perceives the
Slice ID (not others), so it is natural for the service to include a
Slice ID constraint in its TE purpose definition. For example, VPN
routes may have Color attribute (refer to
[I-D.ietf-idr-tunnel-encaps] and
[I-D.ietf-spring-segment-routing-policy]). Color represents a
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specific TE purpose, which can contain a Slice ID. Thus it is
natural carry Slice ID in PCEP message.
When the controller receives the path computation request with a
Slice ID constraint, it can use the resources identified by specific
Slice in TED, or firstly look up the Slice ID to SA-ID mapping entry
and then use the resources of specific SA-ID in TED, to calculate the
path.
In a PCReq message, a PCC MAY insert one Slice-id TLV to indicate the
slice based virtual network that MUST be considered by the PCE. The
PCE will perform path computation based on the intra-domain or inter-
domain sub-topology identified by the specific Slice-id, which is
independent of routing protocols such as IGP/BGP. The absence of the
Slice-id TLV MUST be interpreted by the PCE as a path computation
request for which no constraints need be applied to any of slice,
i.e, a default Slice-id (0) will be applied.
In a PCRep/PCInit/PCUpd message, the Slice-id TLV MAY be carried so
as to provide the network slicing information for the computed path.
The headend may put the Slice-id to an encapsulated data packet.
The format of the Slice-id TLV is shown as Figure 3:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=TBD3 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Slice-id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Slice-id TLV
The code point for the TLV type is TBD3. The TLV length is 4 octets.
Slice-id (32 bits): indicate the Slice-id information. The Slice-id
is also termed as AII defined in [I-D.peng-lsr-network-slicing] to
represent an IETF Network Slice that is defined in
[I-D.ietf-teas-ietf-network-slice-definition].
3.4. Application Specific TLV
The Application Specific TLV is optional and is defined to carry the
application specific constraints.
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In a PCReq message, a PCC MAY insert one Application Specific TLV to
indicate the application that MUST be considered by the PCE. The PCE
will perform path computation using the specific application
attributes. The absence of the Application Specific TLV MUST be
interpreted by the PCE as a path computation request for which no
constraints need be applied to any of the Application Specific
attributes.
In a PCRep/PCInit/PCUpd message, the Application Specific TLV MAY be
inserted so as to provide the Application Specific information for
the computed path.
The format of the Application Specific TLV is shown as Figure 4:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=TBD4 | Length=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Standard Application ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| User Defined Application ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Application Specific TLV
The code point for the TLV type is TBD4. The TLV length is 8 octets.
Standard Application ID: Represents a bit-position value for a single
STANDARD application that is defined in the IANA "IGP Parameters"
registries under the "Link Attribute Applications" registry
[RFC8919].
User Defined Application ID: Represents a single user defined
application which is a specific implementation.
3.5. Color TLV
The Color TLV is optional and is defined to carry the color
constraints.
In a PCReq message, a PCC MAY insert one Color TLV to indicate the
traffic engineering purpose that is recognized by both PCE and PCC
with no conflict meaning. The PCE will perform path computation
based on the color template. The same color template may be also
defined at PCC and the existing constraints (i.e, metric, bandwidth,
delay, etc) carried in the message MUST be ignored. The absence of
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the Color TLV MUST be interpreted by the PCE as a path computation
request for which traditional constraints that are contained in
message need be applied.
In a PCRep/PCInit/PCUpd message, the Color TLV MAY be inserted so as
to provide the TE purpose information for the computed path, the PCC
recognize the color value that match a local color-template. For
example, the COLOR TLV can be used to identify the Color of each
Candidate Path in the Composite Candidate Path as decribed in
[I-D.ietf-pce-multipath]
The format of the Color TLV is shown as 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=TBD5 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Color |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: Color TLV
The code point for the TLV type is TBD5. The TLV length is 4 octets.
Color (32 bits): indicate a TE template, 0 is invalid value. It is
consistent with the Color Extended Community defined in
[I-D.ietf-idr-tunnel-encaps], and color of SR policy defined in
[I-D.ietf-spring-segment-routing-policy].
Note that Color TLV defined in this document is used to represent a
TE template, it can be suitable for any TE instance such as RSVP-TE,
SR-TE, SR-policy. [I-D.ietf-pce-segment-routing-policy-cp] has
proposed the SR policy KEY (that also includes a color information)
as an association group KEY to associate many candidate paths,
however it is only for association purpose but not constraint purpose
for path computation.
A color template can be defined to contain existing constraints such
as metric, bandwidth, delay, affinity parameters, and the sub-
topology constraints above defined in this document.
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3.6. FA-id TLV
FA-id defined in [I-D.ietf-lsr-flex-algo] is a short mapping of SR
policy color to optimize segment stack depth for the IGP area partial
of the entire SR policy. The overlay service that want to be carried
over a particular SR-FA path must firstly let the SR policy supplier
know that requirement. There are two possible ways to map a color to
an FA-id. One is explicit mapping configuration within color
template, the other is dynamicly replacing a long segment list to
short FA segment by headend or controller once the constraints
contained in the color-template equal to that contained in FAD.
In addition to the above mapping behavior, it is also possible to
merge the constraints contained in the color-template and constraints
contained in FAD. The merging behavior can be used to compute SR-TE
path within a Flex-algo plane.
In a PCReq message, a PCC MAY insert one FA-id TLV to indicate the
above explicit FA-id mapping or merging. For mapping case, the PCE
will perform path computation based on the FA-id mapping. In
detailed, The PCE will check if there are connectivity within the
corresponding Flex-algo plane to the destination. If yes, the path
computation result will be represented as segment list with a single
prefix-SID@FA for intra-domain case, or several prefix-SID@FA for
inter-domain case.
For merging case, the PCE will perform path computation based on the
total constraints combinded with the ones contained in FAD identified
by FA-id and other ones contained in PCReq message. The later
constraints can get from color template or directly represent by a
color. In this case the computed path will be limited in the
specific Flex-algo plane determined by link resource Including/
Excluding rules of FAD, and at the same time the path will also meet
other constraints for the TE purpose within the Flex-algo plane. The
PCE can optimize the strictly path to a loosely path when a part of
the strictly path is consistent with the algorithm based path, i.e,
some consecutive adjacency SIDs can be replaced with a single
algorithm based Prefix-SID.
In a PCRep/PCInit/PCUpd message, the FA-id TLV MAY be inserted so as
to provide the FA plane information for the computed path.
In general, the FA-id TLV is only meaningful for the domain (ingress
domain) that headend node belongs to. For inter-domain case,
operator SHOULD ensure the FA-id configuration of different domain
are same for an E2E slice, when he want to explicitly indicate FA-id
in PCEP message, otherwise the PCE has to choose different FA-id for
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other domain as long as the contents of FAD is consistent with the
one of ingress domain.
The format of the FA-id TLV is shown as 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type=TBD6 | Length=4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| FA-id | Flags |M| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: FA-id TLV
The code point for the TLV type is TBD6. The TLV length is 4 octets.
FA-id (8 bits): indicate an explicit FA-id mapping information.
Flags (8 bits): Currently only one flag, Flag-M, is defined.
Flag-M: Indicate mapping behavior when unset, and merging behavior
when set.
4. Security Considerations
TBA
5. Acknowledgements
TBA
6. IANA Considerations
IANA is requested to make allocations from the registry, as follows:
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+--------+----------------------------+------------------+
| Type | TLV | Reference |
+--------+----------------------------+------------------+
| TBD1 | Source Protocol TLV | [this document] |
| TBD2 | Multi-topology TLV | [this document] |
| TBD3 | Slice-id TLV | [this document] |
| TBD4 | Application Specific TLV | [this document] |
| TBD5 | Color TLV | [this document] |
| TBD6 | FA-id TLV | [this document] |
+--------+----------------------------+------------------+
Table 1
7. Normative References
[I-D.bestbar-teas-ns-packet]
Saad, T., Beeram, V. P., Wen, B., Ceccarelli, D., Halpern,
J., Peng, S., Chen, R., Liu, X., and L. M. Contreras,
"Realizing Network Slices in IP/MPLS Networks", draft-
bestbar-teas-ns-packet-02 (work in progress), February
2021.
[I-D.ietf-idr-tunnel-encaps]
Patel, K., Velde, G. V. D., Sangli, S. R., and J. Scudder,
"The BGP Tunnel Encapsulation Attribute", draft-ietf-idr-
tunnel-encaps-22 (work in progress), January 2021.
[I-D.ietf-lsr-flex-algo]
Psenak, P., Hegde, S., Filsfils, C., Talaulikar, K., and
A. Gulko, "IGP Flexible Algorithm", draft-ietf-lsr-flex-
algo-15 (work in progress), April 2021.
[I-D.ietf-pce-multipath]
Koldychev, M., Sivabalan, S., Saad, T., Beeram, V. P.,
Bidgoli, H., Yadav, B., and S. Peng, "PCEP Extensions for
Signaling Multipath Information", draft-ietf-pce-
multipath-00 (work in progress), May 2021.
[I-D.ietf-pce-segment-routing-policy-cp]
Koldychev, M., Sivabalan, S., Barth, C., Peng, S., and H.
Bidgoli, "PCEP extension to support Segment Routing Policy
Candidate Paths", draft-ietf-pce-segment-routing-policy-
cp-04 (work in progress), March 2021.
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[I-D.ietf-spring-segment-routing-policy]
Filsfils, C., Talaulikar, K., Voyer, D., Bogdanov, A., and
P. Mattes, "Segment Routing Policy Architecture", draft-
ietf-spring-segment-routing-policy-11 (work in progress),
April 2021.
[I-D.ietf-teas-ietf-network-slice-definition]
Rokui, R., Homma, S., Makhijani, K., Contreras, L. M., and
J. Tantsura, "Definition of IETF Network Slices", draft-
ietf-teas-ietf-network-slice-definition-01 (work in
progress), February 2021.
[I-D.peng-lsr-network-slicing]
Peng, S., Chen, R., and G. Mirsky, "Packet Network Slicing
using Segment Routing", draft-peng-lsr-network-slicing-00
(work in progress), February 2019.
[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/info/rfc2119>.
[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>.
[RFC4915] Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P.
Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF",
RFC 4915, DOI 10.17487/RFC4915, June 2007,
<https://www.rfc-editor.org/info/rfc4915>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/info/rfc5120>.
[RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
Element (PCE) Communication Protocol (PCEP)", RFC 5440,
DOI 10.17487/RFC5440, March 2009,
<https://www.rfc-editor.org/info/rfc5440>.
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016,
<https://www.rfc-editor.org/info/rfc7752>.
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[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/info/rfc8174>.
[RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path
Computation Element Communication Protocol (PCEP)
Extensions for Stateful PCE", RFC 8231,
DOI 10.17487/RFC8231, September 2017,
<https://www.rfc-editor.org/info/rfc8231>.
[RFC8919] Ginsberg, L., Psenak, P., Previdi, S., Henderickx, W., and
J. Drake, "IS-IS Application-Specific Link Attributes",
RFC 8919, DOI 10.17487/RFC8919, October 2020,
<https://www.rfc-editor.org/info/rfc8919>.
Authors' Addresses
Shaofu Peng
ZTE Corporation
No.50 Software Avenue
Nanjing, Jiangsu 210012
China
Email: peng.shaofu@zte.com.cn
Quan Xiong
ZTE Corporation
No.6 Huashi Park Rd
Wuhan, Hubei 430223
China
Email: xiong.quan@zte.com.cn
Fengwei Qin
China Mobile
Beijing
China
Email: qinfengwei@chinamobile.com
Mike Koldychev
Cisco Systems
Canada
Email: mkoldych@cisco.com
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Siva Sivabalan
Ciena Corporation
Canada
Email: ssivabal@ciena.com
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