wdiff draft-ietf-idr-flowspec-interfaceset-03.txt draft-ietf-idr-flowspec-interfaceset-04.txt

Inter-Domain Routing Area Working Group S. Litkowski
Internet-Draft Orange
Intended status: Standards Track A. Simpson
Expires: September 12, 2017 December 30, 2018 Nokia
K. Patel
Arrcus, Inc
J. Haas
Juniper Networks
L. Yong
Huawei
March 11, 2017
June 28, 2018

Applying BGP flowspec rules on a specific interface set
draft-ietf-idr-flowspec-interfaceset-03
draft-ietf-idr-flowspec-interfaceset-04

Abstract

The BGP flowspec is an Flow Specification (flowspec) Network Layer Reachability
Information (BGP NLRI) extension ([RFC5575]) is used to BGP that allows for the dissemination
of distribute
traffic flow specification rules. specifications into BGP. The primary application of
this extension is DDoS mitigation where the flowspec rules are applied in
most cases to all peering routers distribution of traffic filtering policies for
the network.

This document will present another use case mitigation of BGP flowspec where distributed denial of service (DDoS) attacks.

By default, flow specifications specification filters are used to maintain some access control lists at
network boundary. applied on all forwarding
interfaces that are enabled for use by the BGP flowspec is extension. A
network operator may wish to apply a very efficient distributing
machinery that can help in saving OPEX while deploying/updating ACLs.
This new application requires flow specification rules given filter selectively to be applied
only on a specific
subset of interfaces and in a specific direction.

The current specification of BGP flowspec ([RFC5575]) introduces the
notion of flow specification (which describes the matching criterion)
and traffic filtering actions. The flow specification is encoded as
part of the NLRI while the traffic filtering actions are encoded as
extended communities. The combination of a flow specification and
one or more actions is known as a flow specification rule. [RFC5575]
does not detail where the flow specification rules need to be
applied.

Besides the flow specification and traffic filtering actions, this
document introduces the notion based on an internal classification scheme.
Examples of traffic filtering scope in order to
drive where a particular rule must be applied. In particular, this include "all customer interfaces", "all peer
interfaces", "all transit interfaces", etc.

This document introduces the "interface-set" traffic filtering scope defines BGP Extended Communities ([RFC4360]) that
could
permit such filters to be used in parallel of traffic filtering actions (marking,
rate-limiting ...). The purpose of this extension is selectively applied to inform
remote routers about groups sets of forwarding
interfaces where the rule must be
applied.

This extension can also be used in a DDoS mitigation context where sharing a
provider wants common group identifier. The BGP Extended
Communities carrying this group identifier are referred to apply as the filtering only on specific peers. BGP
Flowspec "interface-set" Extended Communities.

Requirements Language

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].

Status of This Memo

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provisions of BCP 78 and BCP 79.

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This Internet-Draft will expire on September 12, 2017. December 30, 2018.

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Table of Contents

1. Use case . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Specific filtering for DDoS . . . . . . . . . . . . . . . 3
1.2. ACL maintenance . . . . . . . . . . . . . . . . . . . . . 4
2. Collaborative filtering and managing filter direction . . . . 5
3. Traffic filtering scope . . . . . . . . . . . . . . . . . . . 6
4. Interface specific filtering using BGP flowspec . . . . . . . 7
5. 3
3. Interface-set extended community . . . . . . . . . . . . . . 8
6. Handling 4
4. Scaling of per-interface rules from different sources in the processing pipe 9
6.1. Combining Policy Based Routing with BGP flowspec and
interface-set . . . . . . . . . . . . . . . . . . . . 6
5. Deployment Considerations . . 10
6.2. Combining flow collection with BGP flowspec and
interface-set . . . . . . . . . . . . . . . . 6
5.1. Add-Paths . . . . . . 11
7. Scaling of per interface rules . . . . . . . . . . . . . . . 11
8. Deployment considerations . . . 6
5.2. Inter-domain Considerations . . . . . . . . . . . . . . . 12
9. 6
6. Security Considerations . . . . . . . . . . . . . . . . . . . 12
10. 7
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
11. 7
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
11.1. 7
8.1. FlowSpec Transitive Extended Communities . . . . . . . . 13
11.2. 7
8.2. FlowSpec Non-Transitive Extended Communities . . . . . . 13
11.3. 7
8.3. FlowSpec interface-set Extended Community . . . . . . . 13
11.4. . 8
8.4. Allocation Advice to IANA . . . . . . . . . . . . . . . 13
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
12.1. 8
9. Normative References . . . . . . . . . . . . . . . . . . 14
12.2. Informative References . . . . . . . . . . . . . . . . . 14 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 9

1. Use case

1.1. Specific filtering for DDoS

Figure 1

The figure 1 above displays

While a typical service provider Internet network owing Customers, Peers and Transit. To protect pro actively
against some attacks (e.g. DNS, NTP ...), the service provider may
want provide connectivity to deploy some rate-limiting a homogenous class of some flows on peers and transit
links. But depending on link bandwidth, the provider may want to
apply different rate-limiting values.

For 4*10G links peer/transit,
users, it may want often provides connectivity to apply a rate-limiting different groups of
DNS flows users.
The nature of 1G, while these different groups, and how they're classified,
varies based on 10G links, the rate-limiting would be set
to 250Mbps. Customer interfaces must not be rate-limited.

BGP flowspec infrastructure may already be present on purpose of the network. In an enterprise
network, connectivity may exist between data centers, offices, and all PEs may have
external connectivity. In a BGP session running flowspec address family.
The flowspec infrastructure virtual private networking (VPN)
network, it may be reused by consist of customers in different sites connected
through a VPN, the service provider to
implement core network, and external networks such rate-limiting in
as the Internet. In a very quick manner and being able to
adjust values in future quickly without having to configure each node
one by one. Using traditional Internet service provider (ISP)
network, the current network may consist of points of presence (POPs),
internal infrastructure networks, customer networks, peer networks,
and transit networks.

The BGP flowspec specification, it would
not extension permits traffic filters to be possible distributed
to implement different rate limiter on different
interfaces of routers throughout a same router. The flowspec rule is network. However, these filters often should
not be uniformly applied to all
interfaces in all directions or network interfaces. As an example, a
rate-limiting filter applied to the SMTP protocol may be applied to
customer networks, but not other networks. Similarly, a DDoS attack
on some interfaces where flowspec is
activated the SSH protocol may be deemed appropriate to drop at upstream
peering routers but not customer routers.

By default, BGP flowspec rule set would be the same among filters are applied at all
interfaces.

Section Section 4 will detail interfaces that
permit flowspec filters to be installed. What is needed is a solution way to address this use case
selectively apply those filters to subsets of interfaces in a
network.

2. Interface specific filtering using BGP flowspec.

1.2. ACL maintenance

Figure 2 flowspec

The figure 1 uses case detailed above displays a typical service provider multiservice
network owing Customers, Peers and Transit for Internet, as well as
VPN services. The service provider requires to ensure security require application of
its infrastructure by applying ACLs at network boundary. Maintaining
and deploying ACLs different BGP
flowspec rules on hundreds/thousands different sets of routers is really painful
and time consuming and a service provider would be interested interfaces.

We propose to
deploy/updates ACLs using introduce, within BGP flowspec. In this scenario, depending
on the interface type (Internet customer, VPN customer, Peer, Transit
...) the content flowspec, a traffic filtering
scope that identifies a group of the ACL may interfaces where a particular filter
should be different.

We foresee two main cases :

o Maintaining complete ACLs using flowspec : in this case all the
ingress ACL are maintained and deployed using BGPflowspec. See
section Section 9 for more details on security aspects.

o Requirement applied. Identification of interfaces within BGP flowspec
will be done through group identifiers. A group identifier marks a quick deployment
set of interfaces sharing a new filtering term due to a
security alert : new security alerts often requires a fast
deployment of new ACL terms. Using traditional CLI and hop by hop
provisioning, such deployment takes time and network is
unprotected during this time window. Using BGP flowspec to deploy
such rule, common administrative property. Like a service provider can protect its network in few
seconds. Then the SP can decide to keep the rule permanently in
BGP flowspec or update its ACL or remove community, the entry (in case
equipments are group identifier itself does not vulnerable anymore).

Section Section 4 will detail a solution to address this use case
using BGP flowspec.

2. Collaborative filtering and managing filter direction

[RFC5575] states in Section 5. : "This mechanism have any
significance. It is primarily
designed up to allow an upstream autonomous system the network administrator to perform inbound
filtering in their ingress routers of traffic that associate a given downstream
AS wishes
particular meaning to drop.".

In case of networks collaborating in filtering, there is a use case
for performing outbound filtering. Outbound filtering allows to
apply traffic action one step before and so may allow group identifier value (e.g. group ID#1
associated to prevent
impact like congestions.

----------------------
/ \
| Upstream provider |
\ /
-----------------------
| |
|P2 |P1
----------------------
/ \
| MyAS |
\ /
-----------------------

Figure 3

In the figure above, MyAS Internet customer interfaces). The group identifier is connected to an upstream provider. If
a
malicious traffic comes in from the upstream provider, it local interface property. Any interface may
congestion P1 be associated with one
or P2 links. If MyAS apply inbound filtering on P1/P2 more group identifiers using manual configuration.

When a filtering rule advertised through BGP flowspec, the congestion issue will not flowspec must be solved.

Using collaborative filtering, the upstream provider may propose to
MyAS to filter malicious traffic sent to it. We propose to enhance
[RFC5575] to make myAS able applied
only to send particular sets of interfaces, the BGP flowspec updates (on eBGP
sessions) to BGP UPDATE
will contain the upstream provider to request outbound filtering on
peering interfaces towards MyAS. When the upstream provider will
receive the BGP flowspec update from MyAS, the BGP flowspec update
will contain request for outbound filtering on a specific set of
interfaces. The upstream provider will apply automatically the
requested filter and congestion will be prevented.

3. Traffic filtering scope

We see identifiers associated with the use case described above that some BGP flowspec rules
may need to be applied only on specific elements relevant sets of the network
(interfaces, nodes ...). The basic specification detailed in
[RFC5575] does not address this and does not give any detail on where
the traffic filtering rule need to be applied.
interfaces. In addition to the flow specification (flow matching criterion) and
traffic filtering actions described in [RFC5575], this document
introduces group identifiers, it will also
contain the direction the notion of traffic filtering scope. The traffic filtering scope will describe where a particular flow specification rule must be applied.

Using a traffic filtering scope applied in a BGP flowspec rule is optional.
When a rule does not contain any traffic filtering scope parameter,
[RFC5575] applies.

4. Interface specific filtering using BGP flowspec

The use case detailed above requires application of different BGP
flowspec rules on different set (see
Section 3).

Configuration of interfaces.

We propose to introduce, within BGP flowspec, a traffic filtering
scope that identifies a group of interfaces where a particular filter
should apply on. Identification of identifiers associated to interfaces within may
change over time. An implementation MUST ensure that the filtering
rules (learned from BGP flowspec
will be done through group identifiers. A group identifier marks a
set of interfaces sharing a common administrative property. Like flowspec) applied to a
BGP community, particular interface
are always updated when the group identifier itself does not have any
significance. It is up to the network administrator to associate a
particular meaning to a group identifier value (e.g. group ID#1
associated to Internet customer interfaces). The group identifier is
a local interface property. Any interface may be associated with one
or more group identifiers using manual configuration.

When a filtering rule advertised through BGP flowspec must be applied
only to particular sets of interfaces, the BGP flowspec BGP update
will contain the identifiers associated with the relevant sets of
interfaces. In addition to the group identifiers, it will also
contain the direction the filtering rule must be applied in (see
Section 5).

Configuration of group identifiers associated to interfaces may
change over time. An implementation MUST ensure that the filtering
rules (learned from BGP flowspec) applied to a particular interface
are always updated when the group identifier mapping mapping is changing.

Considering figure 2,

As an example, we can imagine the following design :

o Internet customer interfaces are associated with group-identifier
1.

o VPN customer interfaces are associated with group-identifier 2.

o All customer interfaces are associated with group-identifier 3.

o Peer interfaces are associated with group-identifier 4.

o Transit interfaces are associated with group-identifier 5.

o All external provider interfaces are associated with group-
identifier 6.

o All interfaces are associated with group-identifier 7.

If the service provider wants to deploy a specific inbound filtering
on external provider interfaces only, the provider can send the BGP
flow specification using group-identifier 6 and including for the inbound
direction.

There are some cases where nodes are dedicated to specific functions
(Internet peering, Internet Edge, VPN Edge, Service Edge ...), in
this kind of scenario, there is an interest for a constrained
distribution of filtering rules that are using the interface specific
filtering. Without the constrained route distribution, all nodes
will received all the filters even if they are not interested in
those filters. Constrained route distribution of flowspec filters
would allow for a more optimized distribution.

5. Interface-set extended community

This document proposes a new BGP Route Target extended community
called "flowspec interface-set". This document so expands the
definition of the Route Target extended community to allow a new
value of high order octet (Type field) to be TBD (in addition to the
values specified in [RFC4360]).

In order to ease intra-AS and inter-AS use cases, this document
proposes to have a transitive as well as a non transitive version of
this extended community.

This new BGP Route Target extended community is encoded as follows :

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 (TBD) | 0x02 | Autonomous System Number :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: AS Number (cont.) |O|I| Group Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The flags are :

o O : if set, the flow specification rule MUST be applied in
outbound direction to the interface set referenced by the
following group-identifier.

o I : if set, the flow specification rule MUST be applied in input
direction to the interface set referenced by the following group-
identifier.

Both flags can be set at the same time in the interface-set extended
community leading to flow rule to be applied in both directions. An
interface-set extended community with both flags set to zero MUST be
treated as an error and as consequence, the flowspec update MUST be
discarded. As having no direction indicated as no sense, there is no
need to propagate the filter informations in the network.

The Group Identifier is coded as a 14-bit number (values goes from 0
to 16383).

Multiple instances of the interface-set community may be present in a
BGP update. This may appear if the flow rule need to be applied to
multiple set of interfaces.

Multiple instances of the community in a BGP update MUST be
interpreted as a "OR" operation : if a BGP update contains two
interface-set communities with group ID 1 and group ID 2, the filter
would need to be installed on interfaces belonging to Group ID 1 or
Group ID 2.

As using scenario, there is an interest for a Route Target, route constrained
distribution of flowspec NLRI with
interface-set may be subject to filtering rules that are using the interface specific
filtering. Without the constrained distribution as defined
in [RFC4684]. Constrained route distribution for flowspec routes
using interface-set requires discussion and distribution, all nodes
will be addressed in a
future revision of the document.

6. Handling rules from different sources in received all the processing pipe

A packet on a router may be processed by multiple rules that filters even if they are
originated by different sources (e.g. statically configured, I2RS
ephemeral, BGP ephemeral ...). [RFC5575] does not provide any
guidance regarding the precedence interested in
those filters. Constrained route distribution of BGP flowspec rules compared to
other sources. A filters
would allow for a more optimized distribution.

3. Interface-set extended community

This document proposes a new version of BGP flowspec
[I-D.hares-idr-flowspec-v2] should address these precedence rules
definition in future. Route Target extended community
called the "flowspec interface-set". This document only addresses expands the usage
definition of "interface-set" in the
framework Route Target extended community to allow a new
value of [RFC5575] and the following generic rules SHOULD high order octet (Type field) to be used
by an implementation:

o An inbound 0x07 for the transitive
flowspec rule using interface-set SHOULD be processed
after all existing inbound traffic processing rules (ACL, PBR,
QoS, flow collection ...) and SHOULD be applied before forwarding
decision extended community, or 0x47 for the non-
transitive flowspec interface-set extended community. These are in
addition to the values specified in [RFC4360].

This new BGP Route Target extended community is made. encoded as follows :

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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0x07 or 0x47 | 0x02 | Autonomous System Number :
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
: AS Number (cont.) |O|I| Group Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The flags are :

o An outbound flowspec rule using interface-set SHOULD be processed
after all existing outbound traffic processing rules (ACL, PBR,
QoS, O : if set, the flow collection ...) and SHOULD specification rule MUST be applied after forwarding
decision has been made.

Inbound processing Forwarding Outbound processing
ACL->PBR->BGP_FS in -> Lookup -> PBR->QoS->I2RS->BGP_FS out

Example of packet processing pipe

In the example above, any BGP flowspec rule ([RFC5575]) with an
inbound interface-set is processed after all existing features (ACL,
PBR and QoS) but before the lookup is done. The
outbound BGP
flowspec rules with interface-set are applied after direction to the lookup and
after all any existing feature.

This section gives two examples of combining existing features with
BGP flowspec+interface-set attribute on an interface.

6.1. Combining Policy Based Routing with BGP flowspec and interface-set

In this example, a router has an already configured inbound policy on
an interface IF1 with the following rules:

o Static policy IN:

* Entry 1: from udp 10/8 to 11/8 port 53 then set dscp af11 and
accept

* Entry 2: from tcp 10/8 to 11/8 port 22 then set dscp af22 and
accept

* Entry 3: from tcp 10/8 to 11/8 port 80 then set dscp af11 and
accept

* Entry 4: from ip 10/8 to 11/8 then drop

In addition to this static inbound ACL, the router receives referenced by the
following unordered BGP flowspec version 1 rules with an interface-
set matching IF1. group-identifier.

o flowspec rules IN I :

* from udp 10.0.0.1/32 to 11/8 port 53 then drop

* from tcp 10/8 to 11/8 port 80 then set dscp af32 and accept

* from udp 10/8 to 11/8 then accept

The combination of the static inbound ACL and the inbound "interface-
set" flowspec rules should result in if set, the following packet processing:

o a UDP flow from 10.0.0.1 to 11.0.0.2 on port 53 will specification rule MUST be rejected:
firstly, it is allowed by applied in inbound
direction to the static ACL and DSCP is interface set to af11
but then it is dropped referenced by the flowspec filter.

o a UDP flow from 10.0.0.2 to 11.0.0.2 on port 53 will be accepted
and DSCP will following group-
identifier.

Both flags can be set at the same time in the interface-set extended
community leading to af11.

o a TCP flow from 10.0.0.2 rule to 11.0.0.2 on port 80 will be accepted
and DSCP will be applied in both directions. An
interface-set extended community with both flags set to af32: firstly, the static PBR rule set zero MUST be
treated as an error and as consequence, the
DSCP flowspec update MUST be
discarded. As having no direction indicated as no sense, there is no
need to af11 and accepts the packet, then propagate the flowspec filter
rewrites informations in the network.

The Group Identifier is encoded as a 14-bit number, values 0..16383.

Multiple instances of the DSCP to af32 and accepts it also.

6.2. Combining flow collection with BGP flowspec and interface-set

A router extended community may activate flow collection features (used in collaboration
with Netflow export). Flow collection can be done at input side or
output side. When
present in a router is configured to collect flow
informations on an inbound interface, the flow collection happens
before any BGP update. This may occur if the flowspec rule with interface-set: if a particular
packet flow is denied by needs
to be applied to multiple sets of interfaces.

Multiple instances of the extended community in a BGP flowspec rule, it will still update MUST be
collected.

The same happens
interpreted as a "OR" operation. For example, if a router is configured to collect flow
informations on an outbound interface, the flow collection happens,
and then the BGP flowspec rule is applied: the flow is collected
whatever UPDATE
contains two interface-set extended communities with group ID 1 and
group ID 2, the result filter would need to be installed on interfaces
belonging to Group ID 1 or Group ID 2.

Similar to using a Route Target extended community, route
distribution of the BGP flowspec rule.

7. NLRI with interface-set extended communities
may be subject to constrained distribution as defined in [RFC4684].

4. Scaling of per interface per-interface rules

Without "interface-set", all the interfaces are using

In the same absence of an interface-set extended community, a flowspec filter, while with "interface-set"
filter is applied to all flowspec enabled interfaces. When
interface-set extended communities are present, different interfaces
may have different flowspec filters (with filtering rules, with different terms and actions).
Having such flowspec actions.
These differing rules that are applied on specific interfaces
may create forwarding instructions that may be make it harder to share forwarding
instructions within the forwarding plane: a particular term may be present or not in plane.

Flowspec implementations supporting the
filter of a particular interface.

An implementation interface-set extended
community SHOULD take care about trying to keep sharing
forwarding structures as much as possible in order to limit minimize the scaling impact. How the implementation would do so impact in such
circumstances. How this is accomplished is out of the scope of the this
document.

5. Deployment considerations Considerations

5.1. Add-Paths

There are some cases where a particular BGP flowspec NLRI may be
advertised to different interface groups with a different action.
For example, a service provider may want to discard all ICMP traffic
from customer interfaces to infrastructure addresses and want to
rate-limit the same traffic when it comes from some internal
platforms. These particular cases require ADD-PATH ([RFC7911]) to be
deployed in order to ensure that all paths (NLRI+interface-set group-id+actions) group-
id+actions) are propagated within the BGP control plane. Without
ADD-PATH, only a single "NLRI+interface-set group-id+actions" will be
propagated, so some filtering rules will never be applied.

9. Security

5.2. Inter-domain Considerations

Managing permanent Access Control List

The Group Identifier used by using BGP flowspec as
described in Section 1.2 helps in saving roll out time of such ACL.
However some ACL especially at network boundary are critical for the
network security and loosing the ACL configuration may lead interface-set extended community has
local significance to
network open for attackers.

By design, BGP its provisioning Autonomous System. While
[RFC5575] permits inter-as advertisement of flowspec rules are ephemeral : the flow rule exists in
the router while the BGP session is UP and the BGP path for the rule
is valid. We can imagine a scenario where a Service Provider is
managing the network boundary ACLs by using only flowspec. In this
scenario, if , for example, an attacker succeed NLRI, care must
be taken to make the internal
BGP session not accept these communities when they would result in
unacceptable filtering policies.

Filtering of a router to interface-set extended communities at Autonomous System
border routers (ASBRs) may thus be down , it can open all boundary ACLs on
the node, as flowspec rules will disappear due to desirable.

Note that the BGP session
down.

In reality, default behavior without the chance for such attack interface-set feature
would to occur is low, as boundary
ACLs should protect the BGP session from being attacked.

In order have been to complement install the BGP flowspec solution is such deployment
scenario and provides security against such attack, a service
provider may activate Long lived Graceful Restart
[I-D.uttaro-idr-bgp-persistence] filter on the BGP session owning all flowspec
address family. So in case
enabled interfaces.

6. Security Considerations

This document extends the Security Considerations of BGP session [RFC5575] by
permitting flowspec filters to be down, the BGP paths selectively applied to subsets of flowspec rules would
network interfaces in a particular direction. Care must be retained and taken to
not permit the flowspec action will be
retained.

10. inadvertant manipulation of the interface-set extended
community to bypass expected traffic manipulation.

7. Acknowledgements

Authors would like to thanks Wim Hendrickx and Robert Raszuk for
their valuable comments.

11.

8. IANA Considerations

11.1.

8.1. FlowSpec Transitive Extended Communities

This document requests a new type from the "BGP Transitive Extended
Community Types" extended community registry from the First Come
First Served range. This type name shall be 'FlowSpec Transitive
Extended Communities'. IANA has assigned the value 0x07 to this
type.

This document requests creation of a new registry called "FlowSpec
Transitive Extended Community Sub-Types". This registry contains
values of the second octet (the "Sub-Type" field) of an extended
community when the value of the first octet (the "Type" field) is the
value allocated in this document. The registration procedure for
values in this registry shall be First Come First Served.

11.2.

8.2. FlowSpec Non-Transitive Extended Communities

This document requests a new type from the "BGP Non-Transitive
Extended Community Types" extended community registry from the First
Come First Served range. This type name shall be 'FlowSpec Non-
Transitive Extended Communities'. IANA has assigned the value 0x47
to this type.

This document requests creation of a new registry called "FlowSpec
Non-Transitive Extended Community Sub-Types". This registry contains
values of the second octet (the "Sub-Type" field) of an extended
community when the value of the first octet (the "Type" field) is the
value allocated in this document. The registration procedure for
values in this registry shall be First Come First Served.

11.3.

8.3. FlowSpec interface-set Extended Community

Within the two new registries above, this document requests a new
subtype (suggested value 0x02). This sub-type shall be named
"interface-set", with a reference to this document.

11.4.

8.4. Allocation Advice to IANA

IANA is requested to allocate the values of the FlowSpec Transitive
and Non-Transitive Extended Communities such that their values are
identical when ignoring the second high-order bit (Transitive). See
section 2, [RFC4360]. An example allocation would be 0x09/0x49.

It is suggested to IANA that, when possible, allocations from the
FlowSpec Transitive/Non-Transitive Extended Community Sub-Types
registries are made for transitive or non-transitive versions of
features (section 2, [RFC4360]) that their code point in both
registries is identical.

12. References

12.1.

9. Normative References

[I-D.ietf-idr-rtc-no-rt]
Rosen, E., Patel, K., Haas, J., and R. Raszuk, "Route
Target Constrained Distribution of Routes with no Route
Targets", draft-ietf-idr-rtc-no-rt-06 (work in progress),
November 2016.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-
editor.org/info/rfc2119>.

[RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
Communities Attribute", RFC 4360, DOI 10.17487/RFC4360,
February 2006, <http://www.rfc-editor.org/info/rfc4360>. <https://www.rfc-editor.org/info/rfc4360>.

[RFC4684] Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk,
R., Patel, K., and J. Guichard, "Constrained Route
Distribution for Border Gateway Protocol/MultiProtocol
Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual
Private Networks (VPNs)", RFC 4684, DOI 10.17487/RFC4684,
November 2006, <http://www.rfc-editor.org/info/rfc4684>. <https://www.rfc-editor.org/info/rfc4684>.

[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
<http://www.rfc-editor.org/info/rfc5575>.

12.2. Informative References

[I-D.hares-idr-flowspec-v2]
Hares, S., "BGP Flow Specification Version 2", draft-
hares-idr-flowspec-v2-00 (work in progress), June 2016.

[I-D.uttaro-idr-bgp-persistence]
Uttaro, J.,
<https://www.rfc-editor.org/info/rfc5575>.

[RFC7911] Walton, D., Retana, A., Chen, E., Decraene, B., and J. Scudder,
"Support for Long-lived BGP Graceful Restart", draft-
uttaro-idr-bgp-persistence-03 (work
"Advertisement of Multiple Paths in progress), November
2013. BGP", RFC 7911,
DOI 10.17487/RFC7911, July 2016, <https://www.rfc-
editor.org/info/rfc7911>.

Authors' Addresses

Stephane Litkowski
Orange

Email: stephane.litkowski@orange.com

Adam Simpson
Nokia

Email: adam.1.simpson@nokia.com

Keyur Patel
Arrcus, Inc

Email: keyur@arrcus.com

Jeff

Jeffrey Haas
Juniper Networks

Email: jhaas@juniper.net

Lucy Yong
Huawei

Email: lucy.yong@huawei.com