draft-ietf-ospf-node-admin-tag-00.txt   draft-ietf-ospf-node-admin-tag-01.txt 
Open Shortest Path First IGP S. Hegde Open Shortest Path First IGP S. Hegde
Internet-Draft Juniper Networks, Inc. Internet-Draft Juniper Networks, Inc.
Intended status: Standards Track H. Raghuveer Intended status: Standards Track H. Raghuveer
Expires: April 23, 2015 Expires: September 10, 2015
H. Gredler H. Gredler
Juniper Networks, Inc. Juniper Networks, Inc.
R. Shakir R. Shakir
British Telecom British Telecom
A. Smirnov A. Smirnov
Cisco Systems, Inc. Cisco Systems, Inc.
Z. Li Z. Li
Huawei Technologies Huawei Technologies
B. Decraene B. Decraene
Orange Orange
October 20, 2014 March 9, 2015
Advertising per-node administrative tags in OSPF Advertising per-node administrative tags in OSPF
draft-ietf-ospf-node-admin-tag-00 draft-ietf-ospf-node-admin-tag-01
Abstract Abstract
This document describes an extension to OSPF protocol [RFC2328] to This document describes a mechanism to advertise per-node
add an optional operational capability, that allows tagging and administrative tags in This document describes an extension to OSPF
grouping of the nodes in an OSPF domain. This allows protocol [RFC2328] to add an optional operational capability, that
simplification,ease of management and control over route and path allows tagging and grouping of the nodes in an OSPF domain. This
selection based on configured policies. allows simplification, ease of management and control over route and
path selection based on configured policies.
This document describes the protocol extensions to disseminate per- This document describes the protocol extensions to disseminate per-
node administrative-tags to the OSPFv2 and OSPFv3 protocol. node administrative-tags to the OSPFv2 and OSPFv3 protocol.
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
Status of This Memo Status of this Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 23, 2015. This Internet-Draft will expire on September 10, 2015.
Copyright Notice Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Administrative Tag TLV . . . . . . . . . . . . . . . . . . . . 4
3. Administrative Tag TLV . . . . . . . . . . . . . . . . . . . 3 3. OSPF per-node administrative tag TLV . . . . . . . . . . . . . 4
4. OSPF per-node administrative tag TLV . . . . . . . . . . . . 3 3.1. TLV format . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1. TLV format . . . . . . . . . . . . . . . . . . . . . . . 3 3.2. Elements of procedure . . . . . . . . . . . . . . . . . . 5
4.2. Elements of procedure . . . . . . . . . . . . . . . . . . 4 4. Applications . . . . . . . . . . . . . . . . . . . . . . . . . 6
5. Applications . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 11
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 8.1. Normative References . . . . . . . . . . . . . . . . . . . 11
9.1. Normative References . . . . . . . . . . . . . . . . . . 10 8.2. Informative References . . . . . . . . . . . . . . . . . . 12
9.2. Informative References . . . . . . . . . . . . . . . . . 10 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
This document provides mechanisms to advertise per-node It is useful to assign a per-node administrative tag to a router in
administrative tags in the OSPF Router Information LSA [RFC4970]. In the OSPF domain and use it as an attribute associated with the node.
certain path-selection applications like for example in traffic- The per-node administrative tag can be used in traffic-engineering
engineering or Loop Free Alternate (LFA) backup selection there is a applications to provide different path-selection criteria. It can
need to tag the nodes based on their roles in the network and have also be used to prefer or prune certain paths in Loop Free Alternate
policies to prefer or prune a certain group of nodes. (LFA) backup selection via local policies.
2. Applicability
For the purpose of advertising per-node administrative tags within This document provides mechanisms to advertise per-node
OSPF a new TLV is proposed. Because path selection is a functional administrative tags in the OSPF. Path selection is a functional set
set which applies both to TE and non-TE applications, this new TLV is which applies both to TE and non-TE applications. A new TLV is
carried in the Router Information LSA (RI LSA) [RFC4970] defined for carrying per-node administrative tags and is included in
Router Information LSA [RFC4970] .
3. Administrative Tag TLV 2. Administrative Tag TLV
An administrative Tag is a 32-bit integer value that can be used to An administrative Tag is a 32-bit integer value that can be used to
identify a group of nodes in the OSPF domain. identify a group of nodes in the OSPF domain.
The new TLV defined will be carried within an RI LSA for OSPFV2 and The new TLV defined will be carried within an RI LSA for OSPFV2 and
OSPFV3. Router information LSA [RFC4970] can have link,area or AS OSPFV3. Router information LSA [RFC4970] can have link, area or AS
level flooding scope. Choosing the flooding scope to flood the group level flooding scope. Choosing the flooding scope to flood the group
tags are defined by the policies and is a local matter. tags are defined by the policies and is a local matter.
The TLV specifies one or more administrative tag values. An OSPF The TLV specifies one or more administrative tag values. An OSPF
node advertises the set of groups it is part of in the OSPF domain. node advertises the set of groups it is part of in the OSPF domain.
(for example, all PE-nodes are configured with certain tag value, all (for example, all PE-nodes are configured with certain tag value, all
P-nodes are configured with a different tag value in a domain). The P-nodes are configured with a different tag value in a domain).
total number of admin tags that a given router can advertise in one Multiple TLVs MAY be added in same RI-LSA or in different instance of
TLV is restricted to 64. If more tags are needed, multiple TLVs can the RI LSA as defined in [I-D.acee-ospf-rfc4970bis].
be added in same RI-LSA or in different instance of the RI LSA as
defined in [I-D.acee-ospf-rfc4970bis].
4. OSPF per-node administrative tag TLV 3. OSPF per-node administrative tag TLV
4.1. TLV format 3.1. TLV format
As per [RFC4970], the format of the TLVs within the body of an RI LSA As per [RFC4970], the format of the TLVs within the body of an RI LSA
is the same as the format used by the Traffic Engineering Extensions is the same as the format used by the Traffic Engineering Extensions
to OSPF [RFC3630]. to OSPF [RFC3630].
The LSA payload consists of one or more nested Type/Length/Value The LSA payload consists of one or more nested Type/Length/Value
(TLV) triplets. The format of each TLV is: (TLV) triplets. The format of each TLV is:
0 1 2 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Administrative Tag #1 | | Administrative Tag #1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Administrative Tag #2 | | Administrative Tag #2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// // // //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Administrative Tag #N | | Administrative Tag #N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: OSPF per-node Administrative Tag TLV Figure 1: OSPF per-node Administrative Tag TLV
Type : TBA Type : TBA
Length: A 16-bit field that indicates the length of the value portion Length: A 16-bit field that indicates the length of the value portion
in octets and will be a multiple of 4 octets dependent on the number in octets and will be a multiple of 4 octets dependent on the number
of tags advertised. of tags advertised.
Value: A sequence of multiple 4 octets defining the administrative Value: A sequence of multiple 4 octets defining the administrative
tags. The number of tags carried in this TLV is restricted to 64. tags. Atleast one tag MUST be carried if this TLV is included in the
atleast one tag MUST be carried if this TLV is included in the RI- RI-LSA.
LSA.
4.2. Elements of procedure 3.2. Elements of procedure
Meaning of the Node administrative tags is generally opaque to OSPF. Meaning of the Node administrative tags is generally opaque to OSPF.
Router advertising the per-node administrative tag (or tags) may be Router advertising the per-node administrative tag (or tags) may be
configured to do so without knowing (or even explicitly supporting) configured to do so without knowing (or even explicitly supporting)
functionality implied by the tag. functionality implied by the tag.
Interpretation of tag values is specific to the administrative domain Interpretation of tag values is specific to the administrative domain
of a particular network operator. The meaning of a per-node of a particular network operator. The meaning of a per-node
administrative tag is defined by the network local policy and is administrative tag is defined by the network local policy and is
controlled via the configuration. If a receiving node does not controlled via the configuration. If a receiving node does not
skipping to change at page 5, line 36 skipping to change at page 6, line 34
registry. The future OSPF extensions requiring well known values MAY registry. The future OSPF extensions requiring well known values MAY
define their own data signaling tailored to the needs of the feature define their own data signaling tailored to the needs of the feature
or MAY use capability TLV as defined in [RFC4970]. or MAY use capability TLV as defined in [RFC4970].
Being part of the RI LSA, the per-node administrative tag TLV must be Being part of the RI LSA, the per-node administrative tag TLV must be
reasonably small and stable. In particular, but not limited to, reasonably small and stable. In particular, but not limited to,
implementations supporting the per-node administrative tags MUST NOT implementations supporting the per-node administrative tags MUST NOT
tie advertised tags to changes in the network topology (both within tie advertised tags to changes in the network topology (both within
and outside the OSPF domain) or reachability of routes. and outside the OSPF domain) or reachability of routes.
5. Applications 4. Applications
This section lists several examples of how implementations might use This section lists several examples of how implementations might use
the Node administrative tags. These examples are given only to the Node administrative tags. These examples are given only to
demonstrate generic usefulness of the router tagging mechanism. demonstrate generic usefulness of the router tagging mechanism.
Implementation supporting this specification is not required to Implementation supporting this specification is not required to
implement any of the use cases. It is also worth noting that in some implement any of the use cases. It is also worth noting that in some
described use cases routers configured to advertise tags help other described use cases routers configured to advertise tags help other
routers in their calculations but do not themselves implement the routers in their calculations but do not themselves implement the
same functionality. same functionality.
skipping to change at page 6, line 27 skipping to change at page 7, line 25
[RFC5286] poses operation and management challenges. [RFC5286] poses operation and management challenges.
[I-D.ietf-rtgwg-lfa-manageability] proposes policies which, when [I-D.ietf-rtgwg-lfa-manageability] proposes policies which, when
implemented, will ease LFA operation concerns. implemented, will ease LFA operation concerns.
One of the proposed refinements is to be able to group the nodes One of the proposed refinements is to be able to group the nodes
in IGP domain with administrative tags and engineer the LFA based in IGP domain with administrative tags and engineer the LFA based
on configured policies. on configured policies.
(a) Administrative limitation of LFA scope (a) Administrative limitation of LFA scope
Service provider access infrastructure is frequently designed Service provider access infrastructure is frequently
in layered approach with each layer of devices serving designed in layered approach with each layer of devices
different purposes and thus having different hardware serving different purposes and thus having different
capabilities and configured software features. When LFA hardware capabilities and configured software features.
repair paths are being computed, it may be desirable to When LFA repair paths are being computed, it may be
exclude devices from being considered as LFA candidates based desirable to exclude devices from being considered as LFA
on their layer. candidates based on their layer.
For example, if the access infrastructure is divided into the For example, if the access infrastructure is divided into
Access, Distribution and Core layers it may be desirable for the Access, Distribution and Core layers it may be desirable
a Distribution device to compute LFA only via Distribution or for a Distribution device to compute LFA only via
Core devices but not via Access devices. This may be due to Distribution or Core devices but not via Access devices.
features enabled on Access routers; due to capacity This may be due to features enabled on Access routers; due
limitations or due to the security requirements. Managing to capacity limitations or due to the security requirements.
such a policy via configuration of the router computing LFA Managing such a policy via configuration of the router
is cumbersome and error prone. computing LFA is cumbersome and error prone.
With the Node administrative tags it is possible to assign a With the Node administrative tags it is possible to assign a
tag to each layer and implement LFA policy of computing LFA tag to each layer and implement LFA policy of computing LFA
repair paths only via neighbors which advertise the Core or repair paths only via neighbors which advertise the Core or
Distribution tag. This requires minimal per-node Distribution tag. This requires minimal per-node
configuration and network automatically adapts when new links configuration and network automatically adapts when new
or routers are added. links or routers are added.
(b) LFA calculation optimization (b) LFA calculation optimization
Calculation of LFA paths may require significant resources of
the router. One execution of Dijkstra algorithm is required
for each neighbor eligible to become next hop of repair
paths. Thus a router with a few hundreds of neighbors may
need to execute the algorithm hundreds of times before the
best (or even valid) repair path is found. Manually
excluding from the calculation neighbors which are known to
provide no valid LFA (such as single-connected routers) may
significantly reduce number of Dijkstra algorithm runs.
LFA calculation policy may be configured so that routers Calculation of LFA paths may require significant resources
advertising certain tag value are excluded from LFA of the router. One execution of Dijkstra algorithm is
calculation even if they are otherwise suitable. required for each neighbor eligible to become next hop of
repair paths. Thus a router with a few hundreds of
neighbors may need to execute the algorithm hundreds of
times before the best (or even valid) repair path is found.
Manually excluding from the calculation neighbors which are
known to provide no valid LFA (such as single-connected
routers) may significantly reduce number of Dijkstra
algorithm runs.
LFA calculation policy may be configured so that routers
advertising certain tag value are excluded from LFA
calculation even if they are otherwise suitable.
3. Controlling Remote LFA tunnel termination 3. Controlling Remote LFA tunnel termination
[I-D.ietf-rtgwg-remote-lfa] proposed method of tunneling traffic [I-D.ietf-rtgwg-remote-lfa] proposed method of tunneling traffic
after connected link failure to extend the basic LFA coverage and after connected link failure to extend the basic LFA coverage and
algorithm to find tunnel tail-end routers fitting LFA algorithm to find tunnel tail-end routers fitting LFA
requirement. In most cases proposed algorithm finds more than requirement. In most cases proposed algorithm finds more than
one candidate tail-end router. In real life network it may be one candidate tail-end router. In real life network it may be
desirable to exclude some nodes from the list of candidates based desirable to exclude some nodes from the list of candidates based
on the local policy. This may be either due to known limitations on the local policy. This may be either due to known limitations
skipping to change at page 7, line 45 skipping to change at page 8, line 49
advertising certain tag. Tagging routers allows to both exclude advertising certain tag. Tagging routers allows to both exclude
nodes not capable of serving as Remote LFA tunnel tail-ends and nodes not capable of serving as Remote LFA tunnel tail-ends and
to define a region from which tail-end router must be selected. to define a region from which tail-end router must be selected.
4. Mobile backhaul network service deployment 4. Mobile backhaul network service deployment
The topology of mobile backhaul network usually adopts ring The topology of mobile backhaul network usually adopts ring
topology to save fiber resource and it is divided into the topology to save fiber resource and it is divided into the
aggregate network and the access network. Cell Site aggregate network and the access network. Cell Site
Gateways(CSGs) connects the eNodeBs and RNC(Radio Network Gateways(CSGs) connects the eNodeBs and RNC(Radio Network
Controller) Site Gateways(RSGs)connects the RNCs. The mobile Controller) Site Gateways(RSGs) connects the RNCs. The mobile
traffic is transported from CSGs to RSGs. The network takes a traffic is transported from CSGs to RSGs. The network takes a
typical aggregate traffic model that more than one access rings typical aggregate traffic model that more than one access rings
will attach to one pair of aggregate site gateways(ASGs) and more will attach to one pair of aggregate site gateways(ASGs) and more
than one aggregate rings will attach to one pair of RSGs. than one aggregate rings will attach to one pair of RSGs.
---------------- ----------------
/ \ / \
/ \ / \
/ \ / \
+------+ +----+ Access +----+ +------+ +----+ Access +----+
|eNodeB|---|CSG1| Ring 1 |ASG1|------------- |eNodeB|---|CSG1| Ring 1 |ASG1|-------------
+------+ +----+ +----+ \ +------+ +----+ +----+ \
\ / \ \ / \
\ / +----+ +---+ \ / +----+ +---+
\ +----+ |RSG1|----|RNC| \ +----+ |RSG1|----|RNC|
-------------| | Aggregate +----+ +---+ -------------| | Aggregate +----+ +---+
|ASG2| Ring | |ASG2| Ring |
-------------| | +----+ +---+ -------------| | +----+ +---+
/ +----+ |RSG2|----|RNC| / +----+ |RSG2|----|RNC|
/ \ +----+ +---+ / \ +----+ +---+
/ \ / / \ /
+------+ +----+ Access +----+ / +------+ +----+ Access +----+ /
|eNodeB|---|CSG2| Ring 2 |ASG3|------------ |eNodeB|---|CSG2| Ring 2 |ASG3|------------
+------+ +----+ +----+ +------+ +----+ +----+
\ / \ /
\ / \ /
\ / \ /
----------------- -----------------
Figure 2: Mobile Backhaul Network Figure 2: Mobile Backhaul Network
A typical mobile backhaul network with access rings and aggregate A typical mobile backhaul network with access rings and aggregate
links is show in figure above. The mobile backhaul networks links is shown in figure above. The mobile backhaul networks
deploy traffic engineering due to the strict Service Level deploy traffic engineering due to the strict Service Level
Agreements(SLA). The TE paths may have additional constraints to Agreements(SLA). The TE paths may have additional constraints to
avoid passing via different access rings or to get completely avoid passing via different access rings or to get completely
disjoint backup TE paths. The mobile backhaul networks towards disjoint backup TE paths. The mobile backhaul networks towards
the access side change frequently due to the growing mobile the access side change frequently due to the growing mobile
traffic and addition of new eNodeBs. It's complex to satisfy the traffic and addition of new eNodeBs. It's complex to satisfy the
requirements using cost, link color or explicit path requirements using cost, link color or explicit path
configurations. The node administrative tag defined in this configurations. The node administrative tag defined in this
document can be effectively used to solve the problem for mobile document can be effectively used to solve the problem for mobile
backhaul networks. The nodes in different rings can be assigned backhaul networks. The nodes in different rings can be assigned
skipping to change at page 9, line 11 skipping to change at page 10, line 18
nodes in the network. In a data center environment, the topology nodes in the network. In a data center environment, the topology
is usually highly symmetric with many/all paths having equal is usually highly symmetric with many/all paths having equal
cost. In a long distance network, this is usually less the case cost. In a long distance network, this is usually less the case
for a variety of reasons (e.g. historic, fiber availability for a variety of reasons (e.g. historic, fiber availability
constraints, different distances between transit nodes, different constraints, different distances between transit nodes, different
roles ...). Hence between a given source and destination, a path roles ...). Hence between a given source and destination, a path
is typically preferred over the others, while between the same is typically preferred over the others, while between the same
source and another destination, a different path may be source and another destination, a different path may be
preferred. preferred.
+--------------------+ +--------------------+
| | | |
| +----------+ | | +----------+ |
| | | | | | | |
T-10-T | | T-10-T | |
/| /| | | /| /| | |
/ | / | | | / | / | | |
--+ | | | | | --+ | | | | |
/ +--+-+ 100 | | / +--+-+ 100 | |
/ / | | | | / / | | | |
/ / R-18-R | | / / R-18-R | |
/ / /\ /\ | | / / /\ /\ | |
/ | / \ / \ | | / | / \ / \ | |
/ | / x \ | | / | / x \ | |
A-25-A 10 10 \ \ | | A-25-A 10 10 \ \ | |
/ / 10 10 | | / / 10 10 | |
/ / \ \ | | / / \ \ | |
A-25-A A-25-A | | A-25-A A-25-A | |
\ \ / / | | \ \ / / | |
201 201 201 201 | | 201 201 201 201 | |
\ \ / / | | \ \ / / | |
\ x / | | \ x / | |
\ / \ / | | \ / \ / | |
\/ \/ | | \/ \/ | |
I-24-I 100 100 I-24-I 100 100
| | | | | | | |
| +-----------+ | | +-----------+ |
| | | |
+---------------------+ +---------------------+
Figure 3: Explicit Routing topology Figure 3: Explicit Routing topology
In the above topology, operator may want to enforce the following In the above topology, operator may want to enforce the following
high level explicitly routed policies: - Traffic from A nodes to high level explicitly routed policies: - Traffic from A nodes to
A nodes must not go through I nodes - Traffic from A nodes to I A nodes must not go through I nodes - Traffic from A nodes to I
nodes must not go through R and T nodes With node admin tag, tag nodes must not go through R and T nodes With node admin tag, tag
A can be configured on all A nodes, (similarly I, R, T), and then A can be configured on all A nodes, (similarly I, R, T), and then
configure this single CSPF policy on all A nodes to avoid I nodes configure this single CSPF policy on all A nodes to avoid I nodes
for path calculation. for path calculation.
6. Security Considerations 5. Security Considerations
This document does not introduce any further security issues other This document does not introduce any further security issues other
than those discussed in [RFC2328] and [RFC5340]. than those discussed in [RFC2328] and [RFC5340].
7. IANA Considerations 6. IANA Considerations
This specification updates one OSPF registry: OSPF Router Information This specification updates one OSPF registry: OSPF Router Information
(RI) TLVs Registry (RI) TLVs Registry
i) TBD - Node Admin tag TLV i) TBD - Node Admin tag TLV
8. Acknowledgments 7. Acknowledgments
Thanks to Bharath R, Pushpasis Sarakar and Dhruv Dhody for useful Thanks to Bharath R, Pushpasis Sarakar and Dhruv Dhody for useful
inputs. Thanks to Chris Bowers for providing useful inputs to remove inputs. Thanks to Chris Bowers for providing useful inputs to remove
ambiguity related to tag-ordering. ambiguity related to tag-ordering. Thanks to Les Ginsberg and Acee
Lindem for the inputs.
9. References 8. References
9.1. Normative References 8.1. Normative References
[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, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998. [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering [RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
(TE) Extensions to OSPF Version 2", RFC 3630, September (TE) Extensions to OSPF Version 2", RFC 3630,
2003. September 2003.
[RFC4970] Lindem, A., Shen, N., Vasseur, JP., Aggarwal, R., and S. [RFC4970] Lindem, A., Shen, N., Vasseur, JP., Aggarwal, R., and S.
Shaffer, "Extensions to OSPF for Advertising Optional Shaffer, "Extensions to OSPF for Advertising Optional
Router Capabilities", RFC 4970, July 2007. Router Capabilities", RFC 4970, July 2007.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF [RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
for IPv6", RFC 5340, July 2008. for IPv6", RFC 5340, July 2008.
9.2. Informative References 8.2. Informative References
[I-D.acee-ospf-rfc4970bis] [I-D.acee-ospf-rfc4970bis]
Lindem, A., Shen, N., Vasseur, J., Aggarwal, R., and S. Lindem, A., Shen, N., Vasseur, J., Aggarwal, R., and S.
Shaffer, "Extensions to OSPF for Advertising Optional Shaffer, "Extensions to OSPF for Advertising Optional
Router Capabilities", draft-acee-ospf-rfc4970bis-00 (work Router Capabilities", draft-acee-ospf-rfc4970bis-00 (work
in progress), July 2014. in progress), July 2014.
[I-D.ietf-rtgwg-lfa-manageability] [I-D.ietf-rtgwg-lfa-manageability]
Litkowski, S., Decraene, B., Filsfils, C., Raza, K., Litkowski, S., Decraene, B., Filsfils, C., Raza, K.,
Horneffer, M., and p. psarkar@juniper.net, "Operational Horneffer, M., and p. psarkar@juniper.net, "Operational
management of Loop Free Alternates", draft-ietf-rtgwg-lfa- management of Loop Free Alternates",
manageability-04 (work in progress), August 2014. draft-ietf-rtgwg-lfa-manageability-04 (work in progress),
August 2014.
[I-D.ietf-rtgwg-remote-lfa] [I-D.ietf-rtgwg-remote-lfa]
Bryant, S., Filsfils, C., Previdi, S., Shand, M., and S. Bryant, S., Filsfils, C., Previdi, S., Shand, M., and S.
Ning, "Remote LFA FRR", draft-ietf-rtgwg-remote-lfa-02 Ning, "Remote LFA FRR", draft-ietf-rtgwg-remote-lfa-02
(work in progress), May 2013. (work in progress), May 2013.
[RFC5286] Atlas, A. and A. Zinin, "Basic Specification for IP Fast [RFC5286] Atlas, A. and A. Zinin, "Basic Specification for IP Fast
Reroute: Loop-Free Alternates", RFC 5286, September 2008. Reroute: Loop-Free Alternates", RFC 5286, September 2008.
Authors' Addresses Authors' Addresses
skipping to change at page 12, line 4 skipping to change at page 13, line 16
1194 N. Mathilda Ave. 1194 N. Mathilda Ave.
Sunnyvale, CA 94089 Sunnyvale, CA 94089
US US
Email: hannes@juniper.net Email: hannes@juniper.net
Rob Shakir Rob Shakir
British Telecom British Telecom
Email: rob.shakir@bt.com Email: rob.shakir@bt.com
Anton Smirnov Anton Smirnov
Cisco Systems, Inc. Cisco Systems, Inc.
De Kleetlaan 6a De Kleetlaan 6a
Diegem 1831 Diegem, 1831
Belgium Belgium
Email: as@cisco.com Email: as@cisco.com
Li zhenbin Li zhenbin
Huawei Technologies Huawei Technologies
Huawei Bld. No.156 Beiqing Rd Huawei Bld. No.156 Beiqing Rd
Beijing 100095 Beijing, 100095
China China
Email: lizhenbin@huawei.com Email: lizhenbin@huawei.com
Bruno Decraene Bruno Decraene
Orange Orange
Email: bruno.decraene@orange.com Email: bruno.decraene@orange.com
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