Internet DRAFT - draft-ietf-lsr-ospf-transport-instance
draft-ietf-lsr-ospf-transport-instance
LSR Workgroup A. Lindem
Internet-Draft LabN Consulting, L.L.C.
Intended status: Standards Track Y. Qu
Expires: 21 June 2024 Futurewei
A. Roy
Arrcus, Inc.
S. Mirtorabi
Cisco Systems
19 December 2023
OSPF-GT (Generalized Transport)
draft-ietf-lsr-ospf-transport-instance-06
Abstract
OSPFv2 and OSPFv3 include a reliable flooding mechanism to
disseminate routing topology and Traffic Engineering (TE) information
within a routing domain. Given the effectiveness of these
mechanisms, it is advantageous to use the same mechanism for
dissemination of other types of information within the domain.
However, burdening OSPF with this additional information will impact
intra-domain routing convergence and possibly jeopardize the
stability of the OSPF routing domain. This document presents
mechanisms to advertise this non-routing information in separate OSPF
Generalized Transport (OSPF-GT) instances.
OSPF-GT is not constrained to the semantics as traditional OSPF.
OSPF-GT neighbors are not required to be directly attached since they
are never used to compute hop-by-hop routing. Consequently,
independent sparse topologies can be defined to dissemenate non-
routing information only to those OSPF-GT routers requiring it.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
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This Internet-Draft will expire on 21 June 2024.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Possible Use Cases . . . . . . . . . . . . . . . . . . . . . 4
3.1. MEC Service Discovery . . . . . . . . . . . . . . . . . . 4
3.2. Application Data Dissemination . . . . . . . . . . . . . 4
3.3. Intra-Area Topology for BGP-LS Distribution . . . . . . . 5
3.4. BGP-LS Replacement . . . . . . . . . . . . . . . . . . . 5
4. OSPF-GT Instance . . . . . . . . . . . . . . . . . . . . . . 5
4.1. OSPFv2 Generalized Transport Packet Differentiation . . . 5
4.2. OSPFv3 Generalized Transport Packet Differentiation . . . 6
4.3. OSPF-GT Relationship to Traditional OSPF . . . . . . . . 6
4.4. Network Prioritization . . . . . . . . . . . . . . . . . 6
4.5. OSPF-GT Omission of Routing Calculation . . . . . . . . . 6
4.6. Non-routing Instance Separation . . . . . . . . . . . . . 7
4.7. Non-Routing Sparse Topologies . . . . . . . . . . . . . . 8
4.7.1. Remote Neighbor . . . . . . . . . . . . . . . . . . . 8
4.8. Multiple Topologies . . . . . . . . . . . . . . . . . . . 9
5. OSPF Generialized Transport Information (GTI) Encoding . . . 9
5.1. OSPFv2-GT Information Encoding . . . . . . . . . . . . . 9
5.2. OSPFv3-GT Information Encoding . . . . . . . . . . . . . 10
5.3. Generalized Transport Information (GTI) TLV Encoding . . 10
5.3.1. Top-Level GTI Application TLV . . . . . . . . . . . . 11
6. Manageability Considerations . . . . . . . . . . . . . . . . 12
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
8.1. OSPFv2 Opaque LSA Type Assignment . . . . . . . . . . . . 12
8.2. OSPFv3 LSA Function Code Assignment . . . . . . . . . . . 12
8.3. OSPF-GT Instance Information Top-Level TLV Registry . . . 12
9. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
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10.1. Normative References . . . . . . . . . . . . . . . . . . 13
10.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
OSPFv2 [RFC2328] and OSPFv3 [RFC5340] include a reliable flooding
mechanism to disseminate routing topology and Traffic Engineering
(TE) information within a routing domain. Given the effectiveness of
mechanisms, it is advantageous to use the same mechanism for
dissemination of other types of information within the domain.
However, burdening OSPF with this additional information will impact
intra-domain routing convergence and possibly jeopardize the
stability of the OSPF routing domain. This document presents
mechanisms to advertise this non-routing information in separate OSPF
Generalized Transport (OSPF-GT) instances.
OSPF-GT is not constrained to the semantics as traditional OSPF.
OSPF-GT neighbors are not required to be directly attached since they
are never used to compute hop-by-hop routing. Consequently,
independent sparse topologies can be defined to dissemenate non-
routing information only to those OSPF-GT routers requiring it.
OSPF-GT is independent of any traditional OSPF instance. However, it
does rely on the reachbility calculated by routing protocls, e.g.
OSPF and IS-IS.
This OSPF protocol extension provides functionality similar to
"Advertising Generic Information in IS-IS" [RFC6823]. Additionally,
OSPF is extended to support sparse non-routing overlay topologies
Section 4.7. The usage of the OSPF-like flooding and synchronization
mechanisms were originally standardized for general information
advertisement in the Server Cache Synchronization Protocol (SCSP)
[RFC2334]. However, SCSP never experienced significant adoption due
to its association with the waning Asynchronous Transfer Mode (ATM)
technology.
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.
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3. Possible Use Cases
3.1. MEC Service Discovery
Multi-Access Edge Computing (MEC) plays an important role in 5G
architecture. MEC optimizes the performance for ultra-low latency
and high bandwidth services by providing networking and computing at
the edge of the network [ETSI-WP28-MEC]. To achieve this goal, it's
important to expose the network capabilities and services of a MEC
device to 5G User Equipment (UE), i.e., UEs.
The followings are an incomplete list of the kind of information that
OSPF-GT can be used to advertise:
* A network service is realized using one or more physical or
virtualized hosts in MEC, and the locations of these service
points might change. The auto-discovery of these service
locations can be achieved using an OSPF-GT.
* UEs might be mobile, and MEC should support service continuity and
application mobility. This may require service state transferring
and synchronization. OSPF-GT can be used to synchronize these
states.
* Network resources are limited, such as computing power, storage.
The availability of such resources is dynamic, and OSPF-GT can be
used to populate such information, so applications can pick the
right location of such resources, hence improve user experience
and resource utilization.
3.2. Application Data Dissemination
Typically a network consists of routers from different vendors with
different capabilities, and some applications may want to know
whether a router supports certain functionality or where to find a
router supports a functionality, so it will be ideal if such kind of
information is known to all routers or a group of routers in the
network. For example, an ingress router needs to find an egress
router that supports In-situ Flow Information Telemetry (IFIT)
[I-D.wang-lsr-igp-extensions-ifit] and obtain IFIT parameters.
OSPF-GT can be used to populate such router capabilities/
functionalities without impacting the performance or convergence of
the base OSPF protocol.
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3.3. Intra-Area Topology for BGP-LS Distribution
In some cases, it is desirable to limit the number of BGP-LS
[RFC5572] sessions with a controller to the a one or two routers in
an OSPF domain. However, many times those router(s) do not have full
visibility to the complete topology of all the areas. To solve this
problem without extending the BGP-LS domain, the OSPF LSAs for non-
local areas could be flooded over the OSPF-GT topology using remote
neighbors Section 4.7.1.
3.4. BGP-LS Replacement
This mechansism could also be used to replace BGP-LS [RFC5572]
completely by advertising the entire Link State Database (LSDB) using
an OSPF-GT topology with the controller(s) as remote neighbors
Section 4.7.1. The mechanism could also be extended to advertise IS-
IS LSPs within OSPF-GT Information LSAs as described in Section 5.
However, the details of BGP-LS replacement are beyond the scope of
this document.
4. OSPF-GT Instance
In order to isolate the effects of flooding and processing of non-
routing information, OSPF-GT will be relegated to protocol instances
sepearate from the traditional OSPF routing instances. These
instance(s) should be given lower priority when contending for router
resources including processing, backplane bandwidth, and line card
bandwidth. How that is realized is an implementation issue and is
beyond the scope of this document.
Throughout the document, non-routing refers to routing information
that is not used for IP or IPv6 routing calculations. The OSPF-GT
instances area ideally suited for generalized dissemination of other
types of networking and applicaiton information for other protocols
and layers.
4.1. OSPFv2 Generalized Transport Packet Differentiation
OSPFv2 currently does not offer a mechanism to differentiate OSPF
packets from multiple OSPF instances (including OSPF-GT instances)
sent and received on the same interface. However, the [RFC6549]
provides the necessary packet encoding to support multiple OSPF
protocol instances.
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4.2. OSPFv3 Generalized Transport Packet Differentiation
Fortunately, OSPFv3 already supports separate instances within the
packet encodings. The existing OSPFv3 packet header instance ID
field will be used to differentiate packets received on the same link
(refer to section 2.4 in [RFC5340]).
4.3. OSPF-GT Relationship to Traditional OSPF
In OSPF, we must guarantee that any information we've received is
treated as valid if and only if the router sending it is reachable.
We'll refer to this as the "condition of reachability" in this
document.
OSPF-GT is not dependent on any other OSPF instance. It does,
however, have much of the same as topology information must be
advertised to satisfy the "condition of reachability".
Further optimizations and coupling between OSPF-GT and a traditional
OSPF instance are beyond the scope of this document. This is an area
for future study.
4.4. Network Prioritization
While OSPFv2 (section 4.3 in [RFC2328]) are normally sent with IP
precedence Internetwork Control, any packets sent using OSPF-GT
transport instance will be sent with IP precedence Flash (B'011').
This is only appropriate given that this is a pretty flashy
mechanism.
Similarly, OSPFv3 GT instance packets will be sent with the traffic
class mapped to flash (B'011') as specified in ([RFC5340]).
By setting the IP/IPv6 precedence differently for OSPF-GT instance
packets, traditional OSPF routing instances can be given priority
during both packet transmission and reception. In fact, some router
implementations map the IP precedence directly to their internal
packet priority. However, internal router implementation decisions
are beyond the scope of this document.
4.5. OSPF-GT Omission of Routing Calculation
Since one of the primary advantages of the OSPF-GT is to separate the
routing and non-routing processing and fate sharing, a OSPF-GT
instance SHOULD NOT install any IP or IPv6 routes. OSPF routers
SHOULD NOT advertise any OSPF-GT LSAs containing IP or IPv6 prefixes
and OSPF routers receiving LSAs advertising IP or IPv6 prefixes
SHOULD ignore them. This implies that an OSPF-GT instance Link State
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Database should not include any of the LSAs as shown in Table 1.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OSPFv2 | summary-LSAs (type 3) |
| | AS-external-LSAs (type 5) |
| | NSSA-LSAs (type 7) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OSPFv3 | inter-area-prefix-LSAs (type 2003) |
| | AS-external-LSAs (type 0x4005) |
| | NSSA-LSAs (type 0x2007) |
| | intra-area-prefix-LSAs (type 0x2009) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OSPFv3 Extended LSA | E-inter-area-prefix-LSAs (type 0xA023) |
| | E-as-external-LSAs (type 0xC025) |
| | E-Type-7-NSSA (type 0xA027) |
| | E-intra-area-prefix-LSA (type 0xA029) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: LSAs not included in OSPF-GT
If these LSAs are erroneously advertised, they will be flooded as per
standard OSPF but MUST be ignored by OSPF routers supporting this
specification.
4.6. Non-routing Instance Separation
It has been suggested that an implementation could obtain the same
level of separation between IP routing information and non-routing
information in a single instance with slight modifications to the
OSPF protocol. The authors refute this contention for the following
reasons:
* Adding internal and external mechanisms to prioritize routing
information over non-routing information are much more complex
than simply relegating the non-routing information to a separate
instance as proposed in this specification.
* The instance boundary offers much better separation for allocation
of finite resources such as buffers, memory, processor cores,
sockets, and bandwidth.
* The instance boundary decreases the level of fate sharing for
failures. Each instance may be implemented as a separate process
or task.
* With non-routing information, many times not every router in the
OSPF routing domain requires knowledge of every piece of non-
routing information. In these cases, groups of routers which need
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to share information can be segregated into sparse topologies
greatly reducing the amount of non-routing information any single
router needs to maintain.
4.7. Non-Routing Sparse Topologies
With non-routing information, many times not every router in the OSPF
routing domain requires knowledge of every piece of non-routing
information. In these cases, groups of routers which need to share
information can be segregated into sparse topologies. This will
greatly reduce the amount of information any single router needs to
maintain with the core routers possibly not requiring any non-routing
information at all.
With traditional OSPF, every router in an OSPF area must have every
piece of topological information and every intra-area IP or IPv6
prefix. With non-routing information, only the routers needing to
share a set of information need be part of the corresponding sparse
topology. For directly attached routers, one only needs to configure
the desired topologies on the interfaces with routers requiring the
non-routing information. When the routers making up the sparse
topology are not part of a uniconnected graph, two alternatives
exist. The first alternative is configuring tunnels to form a fully
connected graph including only those routers in the sparse topology.
The second alternative is use remote neighbors as described in
Section 4.7.1.
4.7.1. Remote Neighbor
With sparse topologies, OSPF-GT routers sharing non-routing
information may not be directly connected. OSPF-GT adjacencies with
remote neighbors are formed exactly as they are with regular OSPF
neighbors. The main difference is that a remote OSPF-GT neighbor's
address is configured and IP routing is used to deliver OSPF-GT
protocol packets to the remote neighbor. Other salient feature of
the remote neighbor include:
* All OSPF-GT packets have the remote neighbor's configured IP
address as the IP destination address. This address has be to
reachable using the unicast topology.
* The adjacency is represented in the router Router-LSA as a router
(type-1) link with the link data set to the remote neighbor's
configured IP address.
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* Similar to NBMA networks, a poll-interval is configured to
determine if the remote neighbor is reachable. This value is
normally much higher than the hello interval with 40 seconds
RECOMMENDED as the default.
4.8. Multiple Topologies
For some applications, the information need to be flooded only to a
topology which is a subset of routers of the OSPF-GT instance. This
allows the application specific information only to be flooded to
routers that support the application. An OSPF-GT instance may
support multiple topologies as defined in [RFC4915]. But as pointed
out in Section 4.5, an OSPF-GT instance or topology SHOULD NOT
install any IP or IPv6 routes.
Each topology associated with the OSPF-GT instance MUST be fully
connected in order for the LSAs to be successfully flooded to all
routers in the topology.
5. OSPF Generialized Transport Information (GTI) Encoding
5.1. OSPFv2-GT Information Encoding
Application specific information will be flooded in opaque LSAs as
specified in [RFC5250]. An Opaque LSA option code will be reserved
for Generalized Transport Information (GTI) as described in
Section 8. The GTI LSA can be advertised at any of the defined
flooding scopes (link, area, or autonomous system (AS)).
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LS age | Options | 9, 10, or 11 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TBD1 | Opaque ID (Instance ID) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Advertising Router |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LS sequence number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LS checksum | length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+- TLVs -+
| ... |
g
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Figure 2: OSPFv2-GT Information Opaque LSA
The format of the TLVs within the body of an GTI LSA is as defined in
Section 5.3.
5.2. OSPFv3-GT Information Encoding
Application specific information will be flooded in separate LSAs
with a separate function code. Refer to section A.4.2.1 of
[RFC5340]. for information on the LS Type encoding in OSPFv3, and
section 2 of [RFC8362] for OSPFv3 extended LSA types. An OSPFv3
function code will be reserved for Generalized Transport Information
(GTI) as described in Section 8. Same as OSPFv2-GT, the GTI LSA can
be advertised at any of the defined flooding scopes (link, area, or
autonomous system (AS)). The U bit will be set indicating that
OSPFv3 GTI LSAs should be flooded even if it is not understood.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LS age |1|S12| TBD2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link State ID (Instance ID) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Advertising Router |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LS sequence number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LS checksum | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+- TLVs -+
| ... |
Figure 3: OSPFv3-GT Information LSA
The format of the TLVs within the body of an GTI LSA is as defined in
Section 5.3.
5.3. Generalized Transport Information (GTI) TLV Encoding
The format of the TLVs within the body of the LSAs containing non-
routing information is the same as the format used by the Traffic
Engineering Extensions to OSPF [RFC3630]. The LSA payload consists
of one or more nested Type/Length/Value (TLV) triplets. The format
of each TLV is:
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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 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: TLV Format
5.3.1. Top-Level GTI Application TLV
An Application top-level TLV will be used to encapsulate application
data advertised within GTI LSAs. This top-level TLV may be used to
handle the local publication/subscription for application specific
data. The details of such a publication/subscription mechanism are
beyond the scope of this document. An Application ID is used in the
top-level application TLV and shares the same code point with IS-IS
as defined in [RFC6823].
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 (1) | Length - Variable |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Application ID | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
. Sub-TLVs .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Application ID:
An identifier assigned to this application via the IANA registry,
as defined in RFC 6823 [RFC6823]. Each unique application will
have a unique ID.
Additional Application-Specific Sub-TLVs:
Additional information defined by applications can be encoded as
Sub-TLVs. Definition of such information is beyond the scope of
this document.
Figure 5: Top-Level TLV
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The specific TLVs and sub-TLVs relating to a given application and
the corresponding IANA considerations MUST be specified in the
document corresponding to that application.
6. Manageability Considerations
Since OSPF-GT is partioned into one of more separate instances, all
the existing OSPF management information will be available for that
instance. This will enabled ease in managing individual
applications. Additionally, an the operational data for OSPF-GT LSAs
should include an indication of whether or not the "condition of
reachability" is met for the application.
It is RECOMMENDED that reachability for remote neighors Section 4.7.1
through the unicast topology be reported as part of the operational
data.
7. Security Considerations
The security considerations for OSPF-GT will be similar to those for
OSPFv2 [RFC2328] and OSPFv3 [RFC5340]. However, since OSPF-GT is not
used to update OSPF routing, the consequences of attacks will be
dependent on advertised non-routing information. Document availing
OSPF-GT for non-routing information dissemination MUST documents the
Security Considerations pertaining to this information.
8. IANA Considerations
8.1. OSPFv2 Opaque LSA Type Assignment
IANA is requested to assign an option type, TBD1, for Generalized
Transport Information (GTI) LSA from the "Opaque Link-State
Advertisements (LSA) Option Types" registry.
8.2. OSPFv3 LSA Function Code Assignment
IANA is requested to assign a function code, TBD2, for Generalized
Transport Information (GTI) LSAs from the "OSPFv3 LSA Function Codes"
registry.
8.3. OSPF-GT Instance Information Top-Level TLV Registry
IANA is requested to create a registry for OSPF Generalized Transport
Information (GTI) Top-Level TLVs. The first available TLV (1) is
assigned to the Application TLV Section 5.3. The allocation of the
unsigned 16-bit TLV type are defined in the table below.
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+-------------+-----------------------------------+
| Range | Assignment Policy |
+-------------+-----------------------------------+
| 0 | Reserved (Not to be assigned) |
| | |
| 1 | Application TLV |
| | |
| 2-16383 | Unassigned (IETF Review) |
| | |
| 16383-32767 | Unassigned (FCFS) |
| | |
| 32768-32777 | Experimentation (No assignements) |
| | |
| 32778-65535 | Reserved (Not to be assigned) |
+-----------+-------------------------------------+
Figure 6: GTI Top-Level TLV Registry Assignments
9. Acknowledgement
The authors would like to thank Les Ginsberg for review and comments.
10. References
10.1. Normative References
[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>.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>.
[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>.
[RFC5250] Berger, L., Bryskin, I., Zinin, A., and R. Coltun, "The
OSPF Opaque LSA Option", RFC 5250, DOI 10.17487/RFC5250,
July 2008, <https://www.rfc-editor.org/info/rfc5250>.
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[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>.
[RFC6549] Lindem, A., Roy, A., and S. Mirtorabi, "OSPFv2 Multi-
Instance Extensions", RFC 6549, DOI 10.17487/RFC6549,
March 2012, <https://www.rfc-editor.org/info/rfc6549>.
[RFC6823] Ginsberg, L., Previdi, S., and M. Shand, "Advertising
Generic Information in IS-IS", RFC 6823,
DOI 10.17487/RFC6823, December 2012,
<https://www.rfc-editor.org/info/rfc6823>.
[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>.
[RFC8362] Lindem, A., Roy, A., Goethals, D., Reddy Vallem, V., and
F. Baker, "OSPFv3 Link State Advertisement (LSA)
Extensibility", RFC 8362, DOI 10.17487/RFC8362, April
2018, <https://www.rfc-editor.org/info/rfc8362>.
10.2. Informative References
[ETSI-WP28-MEC]
Sami Kekki, etc., "MEC in 5G Networks", 2018,
<https://www.etsi.org/images/files/ETSIWhitePapers/
etsi_wp28_mec_in_5G_FINAL.pdf>.
[I-D.wang-lsr-igp-extensions-ifit]
Wang, Y., Zhou, T., Qin, F., Chen, H., and R. Pang, "IGP
Extensions for In-situ Flow Information Telemetry (IFIT)
Capability Advertisement", Work in Progress, Internet-
Draft, draft-wang-lsr-igp-extensions-ifit-01, 28 July
2020, <http://www.ietf.org/internet-drafts/draft-wang-lsr-
igp-extensions-ifit-01.txt>.
[RFC2334] Luciani, J., Armitage, G., Halpern, J., and N. Doraswamy,
"Server Cache Synchronization Protocol (SCSP)", RFC 2334,
DOI 10.17487/RFC2334, April 1998,
<https://www.rfc-editor.org/info/rfc2334>.
[RFC5572] Blanchet, M. and F. Parent, "IPv6 Tunnel Broker with the
Tunnel Setup Protocol (TSP)", RFC 5572,
DOI 10.17487/RFC5572, February 2010,
<https://www.rfc-editor.org/info/rfc5572>.
Lindem, et al. Expires 21 June 2024 [Page 14]
Internet-Draft OSPF-GT December 2023
Authors' Addresses
Acee Lindem
LabN Consulting, L.L.C.
301 Midenhall Way
CARY, NC 27513
United States
Email: acee.ietf@gmail.com
Yingzhen Qu
Futurewei
2330 Central Expressway
Santa Clara, CA 95050
United States of America
Email: yingzhen.qu@futurewei.com
Abhay Roy
Arrcus, Inc.
Email: abhay@arrcus.com
Sina Mirtorabi
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134
United States of America
Email: smirtora@cisco.com
Lindem, et al. Expires 21 June 2024 [Page 15]
