Internet DRAFT - draft-peng-lsr-network-slicing
draft-peng-lsr-network-slicing
Networking Working Group Shaofu. Peng
Internet-Draft Ran. Chen
Intended status: Standards Track Gregory. Mirsky
Expires: August 29, 2019 ZTE Corporation
February 25, 2019
Packet Network Slicing using Segment Routing
draft-peng-lsr-network-slicing-00
Abstract
This document presents a mechanism aimed at providing a solution for
network slicing in the transport network for 5G services. The
proposed mechanism uses a unified administrative instance identifier
to distinguish different virtual network resources for both intra-
domain and inter-domain network slicing scenarios. Combined with the
segment routing technology, the mechanism could be used for both
best-effort and traffic engineered services for tenants.
Status of This Memo
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 3
3. Overview of Mechanism . . . . . . . . . . . . . . . . . . . . 3
4. Resource Allocation per AII . . . . . . . . . . . . . . . . . 5
4.1. L3 Link Resource AII Configuration . . . . . . . . . . . 5
4.2. L2 Link Resource AII Configuration . . . . . . . . . . . 5
4.3. Node Resource AII Configuration . . . . . . . . . . . . . 6
5. Interworking with SR Flex-algorithm . . . . . . . . . . . . . 6
5.1. Best-effort Service AII-specific . . . . . . . . . . . . 7
5.2. Traffic Engineering service AII-specific . . . . . . . . 7
6. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.1. intra-domain network slicing . . . . . . . . . . . . . . 8
6.2. inter-domain network slicing via BGP-LS . . . . . . . . . 9
6.3. inter-domain network slicing via BGP-LU . . . . . . . . . 11
7. Implementation suggestions . . . . . . . . . . . . . . . . . 11
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
9. Security Considerations . . . . . . . . . . . . . . . . . . . 12
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
11. Normative references . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
According to 5G context, network slicing is the collection of a set
of technologies to create specialized, dedicated logical networks as
a service (NaaS) in support of network service differentiation and
meeting the diversified requirements from vertical industries.
Through the flexible and customized design of functions, isolation
mechanisms, and operation and management (O&M) tools, network slicing
is capable of providing dedicated virtual networks over a shared
infrastructure. A Network slice instance (NSI) is the realization of
network slicing concept. It is an E2E logical network, which
comprises of a group of network functions, resources, and connection
relationships. An NSI typically covers multiple technical domains,
which includes a terminal, access network (AN), transport network
(TN) and a core network (CN), as well as DC domain that hosts third-
party applications from vertical industries. Different NSIs may have
different network functions and resources. They may also share some
of the network functions and resources.
For a packet network, network slicing requires the underlying network
to support partitioning of the network resources to provide the
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client with dedicated (private) networking, computing, and storage
resources drawn from a shared pool. The slices may be seen as
virtual networks. [I-D.ietf-teas-enhanced-vpn] described a framework
to create virtual networks in a packet network. This document
specifies a detailed mechanism to signal association of shared
resources required to create and manage an NSI.
Currently there are multiple methods that could be used to identify
the virtual network resource, such as Administrative Group (AG)
described in [RFC3630], [RFC5329] and [RFC5305], Extended
Administrative Groups (EAGs) described in [RFC7308], and Multi-
Topology Routing (MTR) described in [RFC5120], [RFC4915] and
[RFC5340]. However, all these methods are not sufficient to meet the
requirements of network slicing service. For example, AG or EAG are
limited to serve as a link color scheme used in TE path computation
to meet the requirements of TE service for a tenant. But it is
difficult to use them for an NSI allocation mapping (assuming that
each bit position of AG/EAG represents an NSI) and, at the same time,
as an IGP FIB identifier for best-effort service for the same tenant.
MTR is limited to serve as an IGP logical topology scheme only used
in the intra-domain scenario, and it is challenging to select inter-
area link resource according to MT-ID when E2E inter-domain TE path
needs to be created for a tenant.
Thus, there needs to be a new characteristic of NSI to isolate
underlay resources. Firstly it could serve as TE criteria for TE
service, and secondly, as an IGP FIB table identifier for best-effort
service. This document introduces a new property of NSI called
"Administrative Instance Identifier" (AII) and corresponding method
of using it.
2. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC2119.
3. Overview of Mechanism
At the initial stage, each link in a physical network can be colored
to conform with network slicing requirements. As previously
mentioned, AII can be used to color links to partition underlay
resource. Also, we may continue to use AG or EAG to color links for
traditional TE purpose within a virtual network specified by an AII.
A single or multiple AIIs could be configured on each intra-domain or
inter-domain link regardless of IGP instance configuration. At the
minimum, a link always belongs to default AII (the value is 0). The
number of AIIs configured on a node's links determines the number of
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virtual networks the node is part of. This document defines a new
extension of the existing IGP-TE mechanisms [RFC3630] and [RFC5305]
to distribute AII information in an AS as a new TE parameter of a
link. An SDN controller, using BGP-LS or another interface, will
have a distinct view of each virtual network specified by AII.
Using the CSPF algorithm, a TE path for any best-effort (BE) or
traffic engineered (TE) service can be calculated within a virtual
network specified by the AII. The computation criteria could be
<AII, min igp-metric> or <AII, traditional TE critierias> for the BE
and TE respectively. Combined with segment routing, the TE path
could be represented as:
o a single node-SID of the destination node, for the best-effort
service in the domain;
o node-SIDs of the border node and the destination node, adjacency-
SID of inter-domain link, for the inter-domain best-effort
service;
o an adjacency-SID list, for P2P traffic engineered service.
Because packets of the best-effort service could be transported over
an MP2P LSP without congestion control, SR best-effort FIB for each
virtual network specified by AII to forward best-effort packets may
be created in the IGP domain. Thus, CSPF computation with criteria
<AII, min igp-metric>is distributed on each node in the IGP domain.
That is similar to the behavior in [Flex-algo], but the distributed
CSPF computation is triggered by AII.
To distinguish forwarding behavior of different virtual networks,
prefix-SID need to be allocated per AII and advertised in the IGP
domain.
For inter-domain case, in addition to the destination node-SID,
several node-SIDs of the domain border node and adjacency-SID of
inter-domain link are also needed to construct the E2E segment list.
The segment list could be computed with the help of the SDN
controller which needs to consider AII information during the
computation. The head-end of the segment list maintains the
corresponding SR-TE tunnel or
[I-D.ietf-spring-segment-routing-policy].
As for the prefix-SID, adjacency-SID needs to be allocated per AII to
distinguish the forwarding behavior of different virtual networks.
For P2P traffic engineering service, especially such as uRLLC
service, it SHOULD not transfer over an MP2P LSP to avoid the risk of
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traffic congestion. The segment list could consist of pure
adjacency-SID per AII specific. The head-end of the segment list
maintains the corresponding SR-TE tunnel or
[I-D.ietf-spring-segment-routing-policy].
However, label stack depth of the segment list MAY be optimized at a
later time based on local policies.
At this moment we can steer traffic of overlay service to the above
SR best-effort FIB, SR-TE tunnel or SR policy instance, for the
specific virtual network. The overlay service could specify a color
for TE purpose, for example, color 1000 means <AII=10, min igp-
metric> to say that I need best-effort forwarding within AII 10
resource, color 1001 means <AII=10, delay=10ms, AG=0x1> to say that I
need traffic engineering forwarding within AII 10 resource,
especially using link with AG equal to 0x1 to reach guarantee of not
exceeding 10ms delay time. Service with color 1000 will be steered
to an SR best-effort FIB entry, or an SR-TE tunnel/policy in case of
inter-domain. Service with color 1001 will be steered to an SR-TE
tunnel/policy.
4. Resource Allocation per AII
4.1. L3 Link Resource AII Configuration
In IGP domain, each numbered or unnumbered L3 link could be
configured with AII information and synchronized among IGP neighbors.
The IGP link-state database will contain L3 links with AII
information to support TE path computation considering AII criteria.
For a numbered L3 link, it could be represented as a tuple <local
node-id, remote node-id, local ip-address, remote ip-address>, for
unnumbered it could be <local node-id, remote node-id, local
interface-id, remote interface-id>. Each L3 link could be configured
to belong to a single AII or multiple AIIs, for each <L3 link, AII>
tuple it would allocate a different adjacency-SID. Note that an L3
link always belongs to default AII(0).
An L3 link that is not part of the IGP domain, such as the special
purpose for a static route, or an inter-domain link, can also be
configured with AII information and allocate adjacency-SID per AII as
the same as IGP links. BGP-LS could be used to collect link state
data with AII information to the controller.
4.2. L2 Link Resource AII Configuration
[I-D.ietf-isis-l2bundles] described how to encode adjacency-SID for
each L2 member link of an L3 parent link. It is beneficial to deploy
LAG or another virtual aggregation interface in network slicing
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scenario. Between two nodes, the dedicated link resources belong to
different virtual networks could be added or removed on demand, they
are treated as L2 member links of a single L3 virtual interface. It
is the single L3 virtual interface that needs to occupy IP resource
and be part of the IGP instance. Creating a new slice-specific link
on demand or removing the old one, is likely to affect some
configurations.
Each L2 member link of an L3 parent link SUGGESTED to be configured
to belong to a single AII, and different L2 member link will have
different single AII configuration, with different adjacency-SID.
Note that in this case, the L3 parent link belongs to default AII(0),
but each L2 member link belongs to the specific non-default AII.
Routing protocol control packets follow the L3 parent link of the L2
member link with the highest priority. At the same time, data
packets that belong to the specific virtual network will pass along
the L2 member link with the specific AII value.
TE path computation based on link-state database need view the
detailed L2 members of an L3 adjacency to select the expected L2 link
resource.
4.3. Node Resource AII Configuration
For topology resource, each node needs to allocate node-SID per AII
when it joins the related virtual network. All nodes in the IGP
domain can run CSPF algorithm with criteria <AII, min IGP metric> to
compute best-effort next-hop to any other destination nodes for a
virtual network AII-specific, based on the link-state database that
containing AII information so that SR best-effort FIB can be
constructed for each AII.
An intra-domain overlay best-effort service belongs to a virtual
network could directly match in the above SR best-effort FIB for the
specific AII, while an inter-domain overlay best-effort service
belongs to a virtual network could be over a segment list containing
domain border node-SID and destination node-SID which could match in
the above SR best-effort FIB for the specific AII.
5. Interworking with SR Flex-algorithm
[I-D.ietf-lsr-flex-algo] introduced a mechanism to do label stack
depth optimization for an SR policy in IGP domain part. As the color
of SR policy defined a TE purpose, traditionally the headend or SDN
controller will compute an expected TE path to meet that purpose. It
is necessary to map a color (32 bits) to an FA-ID (8 bits) when SR
flex-algorithm enabled for an SR policy, besides that, it is
necessary to enable the FA-ID on each node that will join the same FA
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plane manually. However, the FAD could copy the TE constraints
contained in the color template. We need to consider the cost of
losing the flexibility of color when executing the flex-algo
optimization, and also consider the gap between P2P TE requirements
and MP2P SR LSP capability, to reach the right balance when deciding
which SR policy need optimization.
5.1. Best-effort Service AII-specific
As described above, for best-effort service we have already
constructed SR best-effort FIB per AII, that is mostly like [Flex-
algo]. Thus, it is not necessary to map to FA-ID again for a color
template which has defined a best-effort behavior within the
dedicated AII. Of course, if someone forced to remap it, there is no
downside for the operation, the overlay best-effort service (with a
color which defined specific AII, best-effort requirement, and
mapping FA-ID) in IGP domain will try to recurse over <AII, prefix>
or <FA-ID, prefix> FIB entry.
5.2. Traffic Engineering service AII-specific
An SR-TE tunnel/policy that served for traffic engineering service of
a virtual network specified by an AII was generated and computed
according to the relevant color template, which contained specific
AII and some other traditional TE constraints. If we config mapping
FA-ID under the color template, the SR-TE tunnel/policy instance
could inherit forwarding information from corresponding SR Flex-Algo
FIB entry.
6. Examples
In this section, we will further illustrate the point through some
examples. All examples share the same figure below.
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.-----. .-----.
( ) ( )
.--( )--. .--( )--.
+---+----link A1----+-----+ +--- +----link A1----+---+
|PE1|----link A2----|ASBR1|---link A1---|ASBR2|----link A2----|PE2|
| |----link B1----| |---link B1---| |----link B1----| |
+---+----link B2----+-----+ +-- -+----link B2----+---+
( ) ( )
'--( AS1 )--' '--( AS2 )--'
( ) ( )
'-----' '-----'
Figure 1 Network Slicing via AII
Suppose that each link belongs to separate virtual network, e.g.,
link Ax belongs to the virtual network colored by AII A, link Bx
belongs to the virtual network colored by AII B. link x1 has an IGP
metric smaller than link x2, but TE metric lager.
To simplify the use case, each AS just contained a single IGP area.
6.1. intra-domain network slicing
From the perspective of node PE1 in AS1, it will calculate best-
effort forwarding entry for each AII instance (including default AII)
to destinations in the same IGP area. For example:
For <AII=0, destination=ASBR1> entry, forwarding information could be
ECMP during link A1 and link B1, with destination node-SID 100 for
<AII=0, destination=ASBR1>.
For <AII=A, destination=ASBR1> entry, forwarding information could be
link A1, with destination node-SID 200 for <AII=A,
destination=ASBR1>.
For <AII=B, destination=ASBR1> entry, forwarding information could be
link B1, with destination node-SID 300 for <AII=B,
destination=ASBR1>.
It could also initiate an SR-TE instance (SR tunnel or SR policy)
with the particular color template on PE1, PE1 is headend and ASBR1
is destination node. For example:
For SR-TE instance 1 with color template which defined criteria
including {default AII, min TE metric}, forwarding information could
be ECMP during two segment list {adjacency-SID 1002 for <AII=0, link
A2>@PE1} and {adjacency-SID 1004 for <AII=0, link B2>@PE1}.
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For SR-TE instance 2 with the color template which defined criteria
including {AII=A, min TE metric}, forwarding information could be
presented as the segment list {adjacency-SID 2002 for <AII=A, link
A2>@PE1}.
For SR-TE instance 3 with the color template which defined criteria
including {AII=B, min TE metric}, forwarding information could be
presented as the segment list {adjacency-SID 3004 for <AII=B, link
B2>@PE1}.
Furthermore, we can use SR Flex-algo to optimize the above SR-TE
instance. For example, for SR-TE instance 1, we can define FA-ID 201
with FAD that contains the same information as the color template, in
turn, FA-ID 202 for SR-TE instance 2, FA-ID 203 for SR-TE instance 3.
Note that each FA-ID also needs to be enabled on ASBR1. So that the
corresponding SR FA entry could be:
For <FA-ID=201, destination=ASBR1> entry, forwarding information
could be ECMP during link A2 and link B2, with destination node-SID
600 for <FA-ID=201, destination=ASBR1>.
For <FA-ID=202, destination=ASBR1> entry, forwarding information
could be link A2, with destination node-SID 700 for <FA-ID=202,
destination=ASBR1>.
For <FA-ID=203, destination=ASBR1> entry, forwarding information
could be link B2, with destination node-SID 800 for <FA-ID=203,
destination=ASBR1>.
6.2. inter-domain network slicing via BGP-LS
An E2E inner-AS SR-TE instance with particular color template could
be initiated on PE1, PE1 is head-end and PE2 is destination node.
BGP-LS could be used to inform the SDN controller about the underlay
network topology information including AII attribute. Thus the
controller could calculate E2E TE path within the particular virtual
network. For best-effort service, for example:
For SR-TE instance 4 with color template which defined criteria
including {default AII, min IGP metric}, forwarding information could
be segment list {node-SID 100 for <AII=0, destination=ASBR1>,
adjacency-SID 1001 for <AII=0, link A1>@ASBR1, node-SID 400 for <
AII=0, destination=PE2>}.
For SR-TE instance 5 with color template which defined criteria
including {AII=A, min IGP metric}, forwarding information could be
segment list {node-SID 200 for <AII=A, destination=ASBR1>, adjacency-
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SID 1001 for <AII=A, link A1>@ASBR1, node-SID 500 for <AII=A,
destination=PE2>}.
For SR-TE instance 6 with color template which defined criteria
including {AII=B, min IGP metric}, forwarding information could be
segment list {node-SID 300 for <AII=B, destination=ASBR1>, adjacency-
SID 1003 for <AII=B, link B1>@ASBR1, node-SID 600 for <AII=B,
destination=PE2>}.
For TE service, for example:
For SR-TE instance 7 with color template which defined criteria
including {default AII, min TE metric}, forwarding information could
be ECMP during two segment list {adjacency-SID 1002 for <AII=0, link
A2>@PE1, adjacency-SID 1001 for <AII=0, link A1>@ASBR1, adjacency-SID
1002 for <AII=0, link A2>@ASBR2} and {adjacency-SID 1004 for <AII=0,
link B2>@PE1, adjacency-SID 1003 for <AII=0, link B1>@ASBR1,
adjacency-SID 1004 for <AII=0, link B2>@ASBR2}.
For SR-TE instance 8 with color template which defined criteria
including {AII=A, min TE metric}, forwarding information could be
segment list {adjacency-SID 2002 for <AII=A, link A2>@PE1, adjacency-
SID 2001 for <AII=A, link A1>@ASBR1, adjacency-SID 2002 for <AII=A,
link A2>@ASBR2}.
For SR-TE instance 9 with color template which defined criteria
including {AII=B, min TE metric}, forwarding information could be
segment list {adjacency-SID 3004 for <AII=B, link B2>@PE1, adjacency-
SID 3003 for <AII=B, link B1>@ASBR1, adjacency-SID 3004 for <AII=B,
link B2>@ASBR2}.
For TE service, if we use SR Flex-algo to do optimizaztion, the above
forwarding information of each TE instance could inherit the
corresponding SR FA entry, it would look like this:
For SR-TE instance 7, forwarding information could be ECMP during two
segment list {node-SID 600 for <FA-ID=201, destination=ASBR1>,
adjacency-SID 1001 for <AII=0, link A1>@ASBR1, node-SID 600 for < FA-
ID=201, destination=PE2>} and {adjacency-SID 1004 for <AII=0, link
B2>@PE1, adjacency-SID 1003 for <AII=0, link B1>@ASBR1, adjacency-SID
1004 for <AII=0, link B2>@ASBR2}.
For SR-TE instance 8 with color template which defined criteria
including {AII=A, min TE metric}, forwarding information could be
segment list {node-SID 700 for <FA-ID=202, destination=ASBR1>,
adjacency-SID 2001 for <AII=A, link A1>@ASBR1, node-SID 700 for <FA-
ID=202, destination=PE2>}.
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For SR-TE instance 9 with color template which defined criteria
including {AII=B, min TE metric}, forwarding information could be
segment list {node-SID 800 for <FA-ID=203, destination=ASBR1>,
adjacency-SID 3003 for <AII=B, link B1>@ASBR1, node-SID 800 for <FA-
ID=203, destination=PE2>}.
6.3. inter-domain network slicing via BGP-LU
In some deployments, operators adopt BGP-LU to build inter-domain
MPLS LSP, overlay service will be directly over BGP-LU LSP. If
overlay service has TE requirements that defined by a color, that
means that BGP-LU LSP needs to have a sense of color too, i.e., BGP-
LU label could be allocated per color. BGP-LU LSP generated for
specific color will be over intra-domain SR-TE or SR Best-effort path
generated for that color again.
In figure 1, PE2 can allocate and advertise six labels for its
loopback plus color 1, 2, 3, 4, 5, 6 respectively. Suppose color 1
defines {default AII, min IGP metric}, color 2 defines {AII=A, min
IGP metric}, color 3 defines {AII=B, min IGP metric}, and color 4
defines {default AII, min TE metric}, color 5 defines {AII=A, min TE
metric}, color 6 defines {AII=B, min TE metric}. PE2 will advertise
these labels to ASBR2 and ASBR2 then continues to allocate six labels
each for prefix PE2 plus different color. Other nodes will have the
same operation. Ultimately PE1 will maintain six BGP-LU LSP.
For example, the BGP-LU LSP for color 1 will be over SR best-effort
FIB entry node-SID 100 for <AII=0, destination=ASBR1> to pass through
AS1, over adjacency-SID 1001 for <AII=0, link A1>@ASBR1 to pass
inter-AS, over SR best-effort FIB entry node-SID 400 for <AII=0,
destination=PE2> to pass through AS2.
For example, The BGP-LU LSP for color 4 will over SR-TE instance 1
(see section 6.1), or SR best-effort FIB entry node-SID 600 for <FA-
ID=201, destination=ASBR1> (see section 6.1) to pass through 6AS1,
over adjacency-SID 1001 for <AII=0, link A1>@ASBR1 to pass inter-AS,
over SR-TE instance 1' or corresponding SR FA entry to pass through
AS2.
7. Implementation suggestions
As a node often contains control plane and forwarding plane, a
suggestion is that only default AII specific FTN entry need be
installed on forwarding plane, so that there are not any modification
and upgrade requirement for hardware and existing MPLS forwarding
mechanism. FTN entry for non-default AII instance will only be
maintained on the control plane and be used for overlay service
iteration according to next-hop plus color (color will give AII
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information and mapping FA-ID information). Note ILM entry for all
AII need be installed on forwarding plane.
The same suggestion is also appropriate for SR Flex-algo.
8. IANA Considerations
TBD.
9. Security Considerations
TBD.
10. Acknowledgements
TBD.
11. Normative references
[I-D.ietf-isis-l2bundles]
Ginsberg, L., Bashandy, A., Filsfils, C., Nanduri, M., and
E. Aries, "Advertising L2 Bundle Member Link Attributes in
IS-IS", draft-ietf-isis-l2bundles-07 (work in progress),
May 2017.
[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-01 (work in progress), November 2018.
[I-D.ietf-spring-segment-routing-policy]
Filsfils, C., Sivabalan, S., daniel.voyer@bell.ca, d.,
bogdanov@google.com, b., and P. Mattes, "Segment Routing
Policy Architecture", draft-ietf-spring-segment-routing-
policy-02 (work in progress), October 2018.
[I-D.ietf-teas-enhanced-vpn]
Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A
Framework for Enhanced Virtual Private Networks (VPN+)
Service", draft-ietf-teas-enhanced-vpn-01 (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>.
Peng, et al. Expires August 29, 2019 [Page 12]
Internet-Draft Packet Network Slicing using SR February 2019
[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
(TE) Extensions to OSPF Version 2", RFC 3630,
DOI 10.17487/RFC3630, September 2003,
<https://www.rfc-editor.org/info/rfc3630>.
[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>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic
Engineering", RFC 5305, DOI 10.17487/RFC5305, October
2008, <https://www.rfc-editor.org/info/rfc5305>.
[RFC5329] Ishiguro, K., Manral, V., Davey, A., and A. Lindem, Ed.,
"Traffic Engineering Extensions to OSPF Version 3",
RFC 5329, DOI 10.17487/RFC5329, September 2008,
<https://www.rfc-editor.org/info/rfc5329>.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008,
<https://www.rfc-editor.org/info/rfc5340>.
[RFC7308] Osborne, E., "Extended Administrative Groups in MPLS
Traffic Engineering (MPLS-TE)", RFC 7308,
DOI 10.17487/RFC7308, July 2014,
<https://www.rfc-editor.org/info/rfc7308>.
Authors' Addresses
Shaofu Peng
ZTE Corporation
Email: peng.shaofu@zte.com.cn
Ran Chen
ZTE Corporation
Email: chen.ran@zte.com.cn
Peng, et al. Expires August 29, 2019 [Page 13]
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Gregory Mirsky
ZTE Corporation
Email: gregimirsky@gmail.com
Peng, et al. Expires August 29, 2019 [Page 14]