BGP Flow Specification Version 2
draft-hares-idr-flowspec-v2-03
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
|
|
|---|---|---|---|
| Authors | Susan Hares , Donald E. Eastlake 3rd , Chaitanya Yadlapalli , Sven Maduschke | ||
| Last updated | 2021-10-24 (Latest revision 2021-07-26) | ||
| Replaced by | draft-ietf-idr-flowspec-v2 | ||
| RFC stream | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-hares-idr-flowspec-v2-03
IDR Working Group S. Hares
Internet-Draft Hickory Hill Consulting
Intended status: Standards Track D. Eastlake
Expires: 27 April 2022 Futurewei Technologies
C. Yadlapalli
ATT
S. Maduscke
Verizon
24 October 2021
BGP Flow Specification Version 2
draft-hares-idr-flowspec-v2-03
Abstract
BGP flow specification version 1 (FSv1) defined in RFC 8955, RFC
8956, and RFC 9117 describes the distribution of traffic filter
policy (traffic filters and actions) distributed via BGP. Multiple
applications have used BGP FSv1 to distribute traffic filter policy.
These applications include the following: mitigation of denial of
service (DoS), enabling traffic filtering in BGP/MPLS VPNs,
centralized traffic control of router firewall functions, and SFC
traffic insertion.
During the deployment of BGP FSv1 a number of issues were detected
due to lack of consistent TLV encoding for rules for flow
specifications, lack of user ordering of filter rules and/or actions,
and lack of clear definition of interaction with BGP peers not
supporting FSv1. Version 2 of the BGP flow specification (FSv2)
protocol addresses these features. In order to provide a clear
demarcation between FSv1 and FSv2, a different NLRI encapsulates
FSv2.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
Hares, et al. Expires 27 April 2022 [Page 1]
Internet-Draft BGP FlowSpec v2 October 2021
This Internet-Draft will expire on 27 April 2022.
Copyright Notice
Copyright (c) 2021 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
extracted from this document must include Simplified BSD License text
as described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Flow Specification v1 Review . . . . . . . . . . . . . . 5
1.2. Ordering for Flow Specification v2 (FSv2) . . . . . . . . 8
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.1. Definitions and Acronyms . . . . . . . . . . . . . . . . 12
2.2. RFC 2119 language . . . . . . . . . . . . . . . . . . . . 13
3. Flow Specification . . . . . . . . . . . . . . . . . . . . . 13
4. Distribution of Flow Specification Information . . . . . . . 14
4.1. IP header SubTLV (type=1) . . . . . . . . . . . . . . . . 16
4.1.1. IP Destination Prefix (type = 1) . . . . . . . . . . 17
4.1.2. IP Source Prefix (type = 2) ) . . . . . . . . . . . . 18
4.1.3. IP Protocol (type = 3) . . . . . . . . . . . . . . . 18
4.1.4. Port (type = 4) . . . . . . . . . . . . . . . . . . . 19
4.1.5. Destination Port (type = 5) . . . . . . . . . . . . . 19
4.1.6. Source Port (type = 6) . . . . . . . . . . . . . . . 20
4.1.7. ICMP Type (type = 7) . . . . . . . . . . . . . . . . 20
4.1.8. ICMP Code (type = 8) . . . . . . . . . . . . . . . . 20
4.1.9. TCP Flags (type = 9) . . . . . . . . . . . . . . . . 21
4.1.10. Packet length (type = 10) . . . . . . . . . . . . . . 21
4.1.11. DSCP (DiffServe Code Point)(type = 11) . . . . . . . 21
4.1.12. Fragment (type = 12) . . . . . . . . . . . . . . . . 22
4.1.13. Flow Label(type = 13) . . . . . . . . . . . . . . . . 22
4.1.14. Parts of SID (type = 14 . . . . . . . . . . . . . . . 23
4.2. Encoding of Actions (type=2) . . . . . . . . . . . . . . 25
4.2.1. Action 1 - Action Chain operation (ACO) (0x01) . . . 28
4.2.2. Traffic Actions per interface set (TAIS) (0x02) . . . 29
4.2.3. Traffic rate limited by bytes (TRB) (0x6) . . . . . . 30
4.2.4. Traffic Action (TA)(0x7) . . . . . . . . . . . . . . 30
4.2.5. Redirect to IPv4 (RDIPv4)[0x8) . . . . . . . . . . . 31
4.2.6. Traffic marking (TM) (0x9) . . . . . . . . . . . . . 32
Hares, et al. Expires 27 April 2022 [Page 2]
Internet-Draft BGP FlowSpec v2 October 2021
4.2.7. Traffic rate limited by packets (TRP) (12/0xC) . . . 32
4.2.8. Traffic redirect to IPv6 (RDIPv6) (13, 0xD) . . . . . 33
4.2.9. Traffic insertion in SFC (TISFC)(14, OXE) . . . . . . 34
4.2.10. Flow Specification Redirect to Indirection-ID (RDIID)
(0x0F) . . . . . . . . . . . . . . . . . . . . . . . 34
4.2.11. VLAN action (VLAN) (action 0x16, 22) . . . . . . . . 36
4.2.12. TPID action (TPID) (action 0x17, 23) . . . . . . . . 37
4.2.13. Extended Community vs. Action SubTLV formats . . . . 38
4.3. L2 and L2VPN FSv2 Filters . . . . . . . . . . . . . . . . 40
4.4. FSv2 SFC NLRI Traffic Filters . . . . . . . . . . . . . . 42
4.5. Encoding of Actions passed in Wide Communities . . . . . 43
5. Validation of FSv2 NLRI . . . . . . . . . . . . . . . . . . . 44
5.1. Validation of FS NLRI (FSv1 or FSv2) . . . . . . . . . . 44
5.2. Validation of Flow Specification Actions . . . . . . . . 46
5.3. Error handling and Validation . . . . . . . . . . . . . . 47
6. Ordering for Flow Specification v2 (FS-v2) . . . . . . . . . 47
6.1. Ordering of FSv2 NLRI Filters . . . . . . . . . . . . . . 48
6.2. Ordering of the Actions . . . . . . . . . . . . . . . . . 49
6.2.1. Action Chain Operation . . . . . . . . . . . . . . . 50
6.2.2. Summary of FSv2 ordering . . . . . . . . . . . . . . 51
7. Ordering of FS filters for BGP Peers support FSv1 and FSv2 . 52
8. Scalability and Aspirations for FSv2 . . . . . . . . . . . . 53
9. Optional Security Additions . . . . . . . . . . . . . . . . . 54
9.1. BGP FS v2 and BGPSEC . . . . . . . . . . . . . . . . . . 54
9.2. BGP FS v2 with with ROA . . . . . . . . . . . . . . . . . 54
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 55
10.1. Flow Specification V2 SAFIs . . . . . . . . . . . . . . 55
10.2. BGP Capability Code . . . . . . . . . . . . . . . . . . 55
10.3. Filter IP Component types . . . . . . . . . . . . . . . 55
10.4. Filter IP component types . . . . . . . . . . . . . . . 56
11. Security Considerations . . . . . . . . . . . . . . . . . . . 57
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 58
12.1. Normative References . . . . . . . . . . . . . . . . . . 58
12.2. Informative References . . . . . . . . . . . . . . . . . 60
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 61
1. Introduction
Modern IP routers have the capability to forward traffic and to
classify, shape, rate limit, filter, or redirect packets based on
administratively defined policies. These traffic policy mechanisms
allow the operator to define match rules that operate on multiple
fields within header of an IP data packet. Upon a match, the traffic
policy allows actions to be associated with each match rule. These
rules can be more widely defined as "event-condition-action" (ECA)
rules where the event is always the reception of a packet.
Hares, et al. Expires 27 April 2022 [Page 3]
Internet-Draft BGP FlowSpec v2 October 2021
BGP ([RFC4271]) flow specification as defined by [RFC8955],
[RFC8956], [RFC9117] specifies the distribution of traffic filter
policy (traffic filters and actions) via BGP to a mesh of BGP peers
(IBGP and EBGP peers). The traffic filter policy is applied when
packets are received on a router with the flow specification function
turned on. The flow specification protocol defined in [RFC8955],
[RFC8956], and [RFC9117] will be called BGP flow specification
version 1 (BGP FSv1) in this draft.
Some modern IP routers also include the abilities of firewalls which
can match on a sequence of packet events based on administrative
policy. These firewall capabilities allow for user ordering of match
rules and user ordering of actions per match.
Multiple deployed applications currently use BGP FSv1 to distribute
traffic filter policy. These applications include: 1) mitigation of
Denial of Service (DoS), 2) traffic filtering in BGP/MPLS VPNS, and
3) centralized traffic control for networks utilizing SDN control of
router firewall functions, 4) classifiers for insertion in an SFC,
and 5) filters for SRv6 routing.
During the deployment of BGP flow specification v1, the following
issues were detected:
* lack of consistent TLV encoding prevented extension of encodings,
* inability to allow user defined order for filtering rules,
* inability to order actions to provide deterministic interactions
or to allow users to define order for actions, and
* no clearly defined mechanisms for BGP peers which do not support
flow specification v1.
Networks currently cope with some of these issues by limiting the
type of traffic filter policy sent in BGP. Current Networks do not
have a good workaround/solution for applications that receive but do
not understand FSv1 policies.
This document defines version 2 of the BGP flow specification
protocol to address these shortcomings in BGP FSv1. Version 2 of BGP
flow specification will be denoted as BGP FSv2.
BGP FSv1 as defined in [RFC8955], [RFC8956], and [RFC9117] specified
2 SAFIs (133, 134) to be used with IPv4 AFI (AFI = 1) and IPv6 AFI
(AFI=2).
Hares, et al. Expires 27 April 2022 [Page 4]
Internet-Draft BGP FlowSpec v2 October 2021
This document specifies 2 new SAFIs (TBD1, TBD2) for FSv2 to be used
with 5 AFIs (1, 2, 6, 25, and 31) to allow user-ordered lists of
traffic match filters for user-ordered traffic match actions encoded
in Communities (Wide or Extended) or a SubTLV of the FSv2 NRLI.
FSv1 and FSv2 use different AFI/SAFIs to send flow specification
filters. Since BGP AFI/SAFIs perform route selection per AFI/SAFI,
this approach can be termed "ships in the night" based on AFI/SAFI.
FSv1 is a critical component of deployed applications. Therefore,
this specification defines how FSv2 will interact with BGP peers that
support either FSv2 or FSv1 or BGP peers that do not support either
FSv1 or FSv2. It is expected that a transition to FSv2 will occur
over time as new applications require FSv2 extensibility and user-
defined ordering for rules and actions or network operators tire of
the restrictions of FSv1 such as error handling issues and restricted
topologies.
This section contains a short review of FSv1 and an overview of FSv2.
Section 3 contains the definition of flow specification v2.
Section 4 contains the encoding rules for FSv2 and user-based
encoding sent via BGP, and section 5 describes how to validate FSv2
NLRI. Section 6 discusses how to combine FSv2 user-ordered match
rules and FSv1 rules. Section 6 also discusses how to combine user-
ordered actions, FSv1 actions, and default actions. Sections 7-10
address an alternate security mechanism, considerations for IANA,
security in deployments, and manageability.
1.1. Flow Specification v1 Review
The FSv1 NLRI defined in [RFC8955] and [RFC8956] for this policy
include 13 match conditions encoded for the following AFI/SAFIs
* IPv4 traffic: AFI:1, SAFI:133
* IPv6 Traffic: AFI:2 SAFI:133
* BGP/MPLS IPv4 VPN: AFI:1, SAFI: 134
* BGP/MPLS IPv6 VPN: AFI:2, SAFI: 134
If one considers the reception of the packet as an event, then BGP
flow specification describes a set of Event-MatchCondition-Action
(ECA) policies where:
* event is the reception of a packet
Hares, et al. Expires 27 April 2022 [Page 5]
Internet-Draft BGP FlowSpec v2 October 2021
* condition stands for "match conditions" defined in the BGP NLRI as
an n-tuple of component filters, and
* the action is defined taken is either: the default condition
(accept traffic), or a set of actions (1 or more) defined in
Extended BGP Community values [RFC4360].
The flow specification conditions and actions combine to make up FSv1
specification rules. Each FSv1 NLRI must have a type 1 component
(destination prefix) and Extended Communities with FSv1 actions can
be attached to a single NLRI or multiple NLRIs in a BGP packet.
Within an AFI/SAFI pair, FSv1 rules are ordered based on the
components in the packet (types 1-13) ordered from left-most to
right-most and within the component types by value of the component.
Rules are inserted in the rule list by component-based order where a
FSv1 rule with existing component type has higher precedence than one
missing a specific component type,
Since FSv1 specifications ([RFC8955], [RFC8956], and [RFC9117])
specify that the FSv1 NLRI MUST have a destination prefix (as
component type 1) embedded in the flow specification, the FSv1 rules
with destination components are ordered by IP Prefix comparison rules
for IPv4 ([RFC8955]) and IPv6 ([RFC8956]). [RFC8955] specifies that
more specific prefixes (aka longest match) have higher precedence
than that of less specific prefixes AND for prefixes of the same
length the lower IP number is selected (lowest IP value). [RFC8955]
specifies that if the offsets within component 1 are the same, then
the longest match and lowest IP comparison rules from [RFC8955]
apply. If the offsets are different, then the lower offset has
precedence.
These rules work to provide a set of FSv1 rules ordered by IP
Destination Prefix by longest match and lowest IP address. [RFC8955]
also states that the requirement for a destination prefix component
"MAY be relaxed by explicit configuration" Since the rule insertions
are based on comparing component types between two rules in order,
this means the rules without destination prefixes are inserted after
all rules which contain destination prefix component.
The actions specified by FSv1 are:
* accept packet (default)
* traffic flow limitation by bytes (6)
* traffic-action (7)
Hares, et al. Expires 27 April 2022 [Page 6]
Internet-Draft BGP FlowSpec v2 October 2021
* redirect traffic (8)
* mark traffic (9)
* traffic flow limiation by packrts (12)
Figure 1 shows a diagram of the FSv1 logical data structures with 5
rules. If FSv1 rules have destination prefix components (type=1) and
FSv1 rule 5 does not have a destination prefix, then FSv1 rule 5 will
be inserted in the policy after rules 1-4.
+--------------------------------------+
| Flow Specification (FS) |
| Policy |
+--------------------------------------+
^ ^ ^
| | |
| | |
+--------^----+ +-------^-------+ +-------------+
| FS Rule 1 | | FS Rule 2 | ... | FS rule 5 |
+-------------+ +---------------+ +-------------+
: :
: :
...: :........
: :
+---------V---------+ +----V-------------+
| Rule Condition | | Rule Action |
| in BGP NLRIs | | in BGP extended |
| AFIs: 1 and 2 | | Communities |
| SAFI 133, 134 | | |
+-------------------+ +------------------+
: : : : : :
.....: . :..... .....: . :.....
: : : : : :
+----V---+ +---V----+ +--V---+ +-V------+ +--V-----++--V---+
| Match | | match | |match | | Action | | action ||action|
|Operator| |Variable| |Value | |Operator| |variable|| Value|
|*1 | | | | | |(subtype| | || |
+--------+ +--------+ +------+ +--------+ +--------++------+
*1 match operator may be complex.
Figure 1: BGP Flow Specification v1 Policy
Hares, et al. Expires 27 April 2022 [Page 7]
Internet-Draft BGP FlowSpec v2 October 2021
1.2. Ordering for Flow Specification v2 (FSv2)
Flow Specification v2 allows the user to order the flow specification
rules and the actions associated with a rule. Each FSv2 rule may
have one or more match conditions and one or more associated actions.
This FSv2 specification supports the components and actions for the
following
* IPv4 (AFI=1, SAFI: TBD1),
* IPv6 (AFI=2, SAFI: TBD2),
* L2 (AFI=6, SAFI: TDB1),
* BGP/MPLS IPv4 VPN: (AFI=1, SAFI: TBD2),
* BGP/MPLS IPv6 VPN: (AFI=2, SAFI: TBD2),
* BGP/MPLS L2VPN (AFI=25, SAFI: TDB2),
* SFC: (AFI=31, SAFI: TBD1), and
* SFC VPN (AFI=31, SAFI: TBD2).
The FSv2 specification for tunnel traffic is outside the scope of
this specification. The FSv1 specification for tunneled traffic is
in [I-D.ietf-idr-flowspec-nvo3].
FSv2 operates in the ships-in-the night model with FSv1 so network
operators can manipulate FSv2 and FSv1 using configuration
parameters. Since deterministic ordering was a short coming in FSv1,
this specification provides rules and protocol features to keep
filters in a deterministic order.
The basic principles regarding ordering of rules are simple:
1) Rule-0 (zero) is defined to be 0/0 with the "permit-all"
action.
2) FSv2 rules are ordered based on user-specified order.
- The user-specified order is carried FSv2 NLRI with the sentence
that the numerical lower value takes precedence over the
numerically higher value. For rules received with the same
order value, the FSv1 rules apply (order by component type and
then by value of the components).
Hares, et al. Expires 27 April 2022 [Page 8]
Internet-Draft BGP FlowSpec v2 October 2021
3) FSv2 rules are added starting with Rule 1 and FSv1 rules are
added after FSv2 rules.
- For this example, BGP Peer A has FSv2 data base with 10 FSv2
rules (1-10) and 10 FSv1 rules (301-310).
4) An FSv2 peer may receive BGP NLRI routes from a FSv1 peer or a
BGP peer that does not support FSv1 or FSv2. The capabilities
sent by a BGP peer indicate whether the AFI/SAFI can be received
(FSv1 NLRI or FSv2 NLRI).
- Suppose an FSv2 peer (BGP Peer A) has the capability to send
either FSv1 or FSv2. BGP Peer A peers with BGP Peers B, C, D
and E.
- BGP Peer B can only send FSv1 routes (NLRI + Extended
Community). BGP Peer C can send FSv2 routes (NLRI + path
attributes (wide community or extended community or none)).
BGP Peer D cannot send any FS routes. BGP E can send FSv2 and
FSv1 routes
- BGP Peer A sends FSv1 routes in its databases to BGP B. Since
the FSv2 NLRI cannot be sent to the FSv1 peer, only the FSv1
NLRI is sent. BGP Peer A sends to BGP C the FSv2 routes in its
database (configured or received).
- BGP peer A would not send the FSv1 NLRI or FSv2 NLRI to BGP
Peer D. The BGP Peer D does not support for these NLRI.
- BGP Peer A sends the NLRI for both FSv1 and FSv2 to BGP Peer E.
5) Associate a chain of actions to rules based on user-defined
action number
- FSv2 allows actions to be associated by the following: a)
actions in an Extended Community, b) actions in a wide
community, or c) actions within the FSv2 NRLI associated as a
SubTLV.
- Action user-order value zero is reserved.
- An action associated with FSv2 NLRI using in a SubTLV always
has a user-defined order.
- The precedence between two actions with user-defined order
(Wide community) is discussed in detail in section 6.2.
Examples of action chain
Hares, et al. Expires 27 April 2022 [Page 9]
Internet-Draft BGP FlowSpec v2 October 2021
An action associated with FSv2 NLRI using in a SubTLV always has a
user-defined order. If two actions have the same user-defined order
and the same action type, the ordering of the actions within the same
type is defined by the action type (see section 4.2).
The use case for the Action which always associated with an NRLI is
the DDOS match case that always drops the packet in order to kill off
a widespread DDoS attack. The idea is easy, but the deployment
issues may be more complex. An example may help illustrate this
point.
Suppose BGP Peer A has a configured value for FSv2ExtComActionStart
of 10. Suppose BGP Peer A receives the following attributes
associated with the same FSv2 NLRI to form an action chain:
* a Wide Community action with user-defined order 10 from AS 2020
that limits packet-based rate limit of 600 packets per second
* an action SubTLV with a user order of 11 from AS 10 that limits
the packet base rate to zero packets per second,
* a Wide Community with a user order of 11 from AS 2021 that limits
the packet-based rate limit of 50.
The FSv2 data base would store the following action chain:
* at user-defined action order 10:
- a user action type of 12 (packet-based rate limit) with values
of AS 2020 and float value of 1000.
* at user-defined action order 11 in order:
- 1.A user action of type 12 with values of AS 10 and float value
of zero,
- 2. A user action of type 12 with value of AS 2021 and float
value of 50.
When does the action chain stop?
The default process for the action chain is to stop on failure.
If setting the packet-based rate limit of 1000 works, the action
chain would go on to set the value of zero. If this works, it would
go on to set the value to 50. This set of actions may not be what
the user wanted if this is a DDoS attack.
Hares, et al. Expires 27 April 2022 [Page 10]
Internet-Draft BGP FlowSpec v2 October 2021
BGP FSv2 rules are ephemeral by default (just as BGP routes are
ephemeral) upon a restart of a BGP session or a router.
After FSv2 NLRI are checked for errors in syntax, those with valid
syntax are checked for the same validation procedure FSv1 NLRI uses
[RFC8955] and [RFC9117]. See section 5 for for a detailed discussion
of validation and error handling.
Names may be associated with rules or actions in order for network
management protocols (NETCONF/RESTCONF) to be able to provide
detailed reports in the BGP Yang models.
Figure 2 provides a logical diagram of the FSv2 structure
Hares, et al. Expires 27 April 2022 [Page 11]
Internet-Draft BGP FlowSpec v2 October 2021
+--------------------------------+
| Rule Group |
+------------------------------ -+
^ ^ ^
| ---------- |
| | ------
| | |
+--------^-------+ +-------^-----+ +---^-----+
| Rule1 | | Rule2 | ... | Rule-n |
+----------------+ +-------------+ +---------+
: : : :
:.................: : : :
: |.........: : :
+--V--+ +--V--+ : :
| name| |order| .........: :.....
+-----+ +-----+ : :
: :
+----------------V----+ +-----V----------------+
|Rule Match condition | | Rule Action |
+---------------------+ +----------------------+
: : : : : : : : |
+--V--+ : : : +--V---+ : : : V
| Rule| : : : |action| : : : +-----------+
| name| : : : |order | : : : |action name|
+-----+ : : : +------+ : : : +-----------+
: : : : : :...........
: : : : : :
.....: . :..... ..: :..... :
: : : : : :
+----V---+ +---V----+ +--V---+ +-V------++--V-----++--V---+
| Match | | match | |match | | Action || action ||action|
|Operator| |variable| |Value | |Operator||Variable|| Value|
+--------+ +--------+ +------+ +--------++--------++------+
Figure 2: Order Flow Specification Data storage
2. Terminology
2.1. Definitions and Acronyms
AFI - Address Family Identifier
BGPSEC - secure BGP [RFC8205] updated by [RFC8206]
BGP Session ephemeral state - state which does not survive the
loss of BGP peer,
Hares, et al. Expires 27 April 2022 [Page 12]
Internet-Draft BGP FlowSpec v2 October 2021
Ephemeral state - state which does not survive the reboot of a
software module, or a hardware reboot. Ephemeral state can be
ephemeral configuration state or operational state.
configuration state - state which persist across a reboot of
software module within a routing system or a reboot of a hardware
routing device.
NETCONF: The Network Configuration Protocol [RFC6241].
RESTCONF: The RESTCONF configuration Protocol [RFC8040]
ROA: Route Origin Authentication [RFC6482]
SAFI - Subsequent Address Family Identifier
2.2. RFC 2119 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 BCP 14 [RFC2119]
[RFC8174] when, and only when, they appear in all capitals as shown
here.
3. Flow Specification
A BGP Flow Specification is an n-tuple containing several match
criteria that can be applied to IP traffic, traffic encapsulated in
IP traffic or traffic associated with IP traffic. The following
traffic filters are examples of traffic associated with IP traffic:
IP packet or an IP packet inside a L2 packet (Ethernet), an MPLS
packet, and SFC flow.
A given Flow Specification NLRI may be associated with a set of path
attributes depending on the particular application, and attributes
within that set may or may not include reachability information
(e.g., NEXT_HOP). Extended Community or Wide Community attributes
(well-known or AS-specific) MAY be used to encode a set of pre-
determined actions.
A particular application is identified by a specific AFI/SAFI
(Address Family Identifier/Subsequent Address Family Identifier) and
responds to a distinct set of RIBs. Those RIBs should be treated
independently of each other in order to assure noninterference
between distinct applications.
Hares, et al. Expires 27 April 2022 [Page 13]
Internet-Draft BGP FlowSpec v2 October 2021
BGP processing treats the NLRI as a key to entries in AFI/SAFI BGP
databases. Entries that are placed in the Loc-RIB are then
associated with a given set of semantics which are application
dependent. Standard BGP mechanisms such as update filtering by NLRI
or by attributes such as AS_PATH or large communities apply to the
BGP Flow Specification defined NLRI-types.
Network operators can control the propagation of BGP routes by
enabling or disabling the exchange of routes for a particular AFI/
SAFI pair on a particular peering session. As such, the Flow
Specification may be distributed to only a portion of the BGP
infrastructure.
4. Distribution of Flow Specification Information
The BGP Flow Specification version 2 (BGP-FS v2) uses an NRLI with
the format for AFIs for IPv4 (AFI = 1), IPv6 (AFI = 2), L2 (AFI = 6),
L2VPN (AFI=25), and SFC (AFI=31) with two following SAFIs to support
transmission of the flow specification which supports user ordering
of traffic filters and actions for iP traffic and IP VPN traffic.
This NLRI information is encoded using MP_REACH_NLRI and
MP_UNREACH_NLRI attributes defined in [RFC4760]. When advertising
FSv2 NLRI, the length of the Next-Hop Network Address MUST be set to
0. Upon reception, the Network Address of the Next-Hop field MUST be
ignored.
Implementations wishing to exchange flow specification rules MUST use
BGP's Capability Advertisement facility to exchange the Multiprotocol
Extension Capability Code (Code 1) as defined in [RFC4760], and
indicate a capability for flow specification v2 (Code TBD4).
The AFI/SAFI NLRI for BGP Flow Specification version 2 (FSv2) has the
format:
Hares, et al. Expires 27 April 2022 [Page 14]
Internet-Draft BGP FlowSpec v2 October 2021
+-------------------------------+
|length (2 octets) |
+-------------------------------+
| Sub-TLVs (variable) |
| +===========================+ |
| | order (4 octets) | |
| +---------------------------+ |
| | identifier (4 octets) | |
| +---------------------------+ |
| | type (2 octets) | |
| +---------------------------+ |
| | length-Subtlv (2 octets) | |
| +---------------------------+ |
| | value (variable) | |
| +===========================+ |
+-------------------------------+
Figure 3 -Flow Specification v2 format
where:
* length: length of field including all SubTLVs in octets.
- The combined lengths of any FSv2 NLRI in the MP_REACH_NLRI or
MP_UNREACH_NLRI plus the BGP path attributes, the BGP NLRI
length and the BGP header must be less than the packet size.
* order: flow-specification global rule order number (4 octets).
* identifier: identifier for the rule (used for NM/Logging) (4
octets)
* type: contains a type for the TLV format of the NRLI (2 octets)
which can be:
- 0 - reserved,
- 1 - FSv2 IP header traffic rules
- 2 - FSv2 Actions
- 3- FSv2 L2 traffic rules
- 4- FSv2 SFC Traffic rules
* length-tlv: is the length of the value part of the Sub-TLV,
Hares, et al. Expires 27 April 2022 [Page 15]
Internet-Draft BGP FlowSpec v2 October 2021
* value: value depends on the subTLV (see sections below).
4.1. IP header SubTLV (type=1)
The format of the IP header TLV value field is shown in figure 4.
The AFI/SAFI field includes the AFI (2 octets), SAFI (1 octet). The
AFI will be 1 (IPv4) or 2 (IPv6) and the SAFI will be TBD1 or, for
the VPN case, TBD2.
+-------------------------------+
| +--------------------------+ |
| | AFI/SAFI field (3) | |
| | (subTLVs)+ | |
| +==========================+ |
+-------------------------------+
Figure 4 - IP Header TLV
Each SubTLV has the format:
+-------------------------------+
| SubTLV type (1 octet) |
+-------------------------------+
| length (1 octet) |
+ ------------------------------+
| value (variable) |
+-------------------------------+
Figure 5 – IP header SubTLV format
Where:
SubTLV type: component values are defined in the "Flow
Specification Component types" registry for IPv4 and IPv6 by
[RFC8955], [RFC8956], and [I-D.ietf-idr-flowspec-srv6]
length: length of SubTLV (varies depending on SubTLV type).
value: dependent on the subTLV
- For descriptions of value portions for components 1-13 see
[RFC8955] and [RFC8956]. For components 14 see
[I-D.ietf-idr-flowspec-srv6].
Many of the components use the operators [numeric_op] and
[bitmask_op] defined in [RFC8955]
Table 2
Hares, et al. Expires 27 April 2022 [Page 16]
Internet-Draft BGP FlowSpec v2 October 2021
The list of valid subtypes are:
1 - IP Destination prefix
2 - IP Source prefix
3 - IPv4 Protocol / IPv6 Upper Layer Protocol
4 - Port
5 - Destination Port
6 - Source Port
7 - ICMPv4 type / ICMPv6 type
8 - ICMPv4 code / ICPv6 code
9 - TCP Flags
10 - Packet length
11 - DSCP (Diffserv Code Point)
12 - Fragment
13 - Flow Label
14 - Parts of SID
Ordering within the TLV in FSv2: The transmission of SubTLVs within a
flow specification rule must be sent ascending order by SubTLV type.
If the SubTLV types are the same, then the value fields are compared
using mechanisms defined in [RFC8955] and [RFC8956]. NLRIs having
TLVs which do not follow the above ordering rules MUST be considered
as malformed by a BGP FSv2 propagator. This rule prevents any
ambiguities that arises from the multiple copies of the same NLRI
from multiple BGP FSv2 propagators. A BGP implementation SHOULD
treat such malformed NLRIs as "Treat-as-withdraw" [RFC7606].
See [RFC8955] and [RFC8956], and [I-D.ietf-idr-flowspec-srv6]. for
specific details.
4.1.1. IP Destination Prefix (type = 1)
IPv4 Name: IP Destination Prefix (reference: [RFC8955])
IPv6 Name: IPv6 Destination prefix (reference: [RFC8956])
Hares, et al. Expires 27 April 2022 [Page 17]
Internet-Draft BGP FlowSpec v2 October 2021
IPv4 length: Prefix length
IPv4 value: IPv4 Prefix (variable length)
IPv6 length: length of value
IPv6 value: [offset (1 octet)] [pattern (variable)]
[padding(variable)]
If IPv6 length = 0 and offset = 0, then component matches every
address. Otherwise, length must be offset "less than" length "less
than" 129 or component is malformed.
4.1.2. IP Source Prefix (type = 2) )
IPv4 Name: IP Source Prefix (reference: [RFC8955])
IPv6 Name: IPv6 Source prefix (reference: [RFC8956])
IPv4 length: Prefix length
IPv4 value: Source IPv4 Prefix (variable length)
IPv6 length: length of value
IPv6 value: [offset (1 octet)] [pattern
(variable)][padding(variable)]
If IPv6 length = 0 and offset = 0, then component matches every
address. Otherwise, length must be offset < length < 129 or
component is malformed.
4.1.3. IP Protocol (type = 3)
IPv4 Name: IP Protocol IP Source Prefix (reference: [RFC8955])
IPv6 Name: IPv6 Upper-Layer Protocol: (reference: [RFC8956])
IPv4 length: variable
IPv4 value: [numeric_op, value]+
IPv6 length: variable
Hares, et al. Expires 27 April 2022 [Page 18]
Internet-Draft BGP FlowSpec v2 October 2021
IPv6 value: [numeric_op, value}+
where the value following each numeric_op is a single octet.
4.1.4. Port (type = 4)
IPv4/IPv6 Name: Port (reference: [RFC8955]), [RFC8956])
Filter defines: a set of port values to match either destination port
or source port.
IPv4 length: variable
IPv4 value: [numeric_op, value]+
IPv6 length: variable
IPv6 value: [numeric_op, value]+
where the value following each numeric_op is a single octet.
Note-1: In the presence of the port component (destination or source
port), only a TCP (port 6) or UDP (port 17) packet can match the
entire flow specification. If the packet is fragmented and this is
not the first fragment, then the system may not be able to find the
header. At this point, the FSv2 filter may fail to detect the
correct flow. Similarly, if other IP options or the encapsulating
security payload (ESP) is present, then the node may not be able to
describe the transport header and the FSv2 filter may fail to detect
the flow.
This problem comes from the inheritance of the FSv1 filter component
for port. If better resolution is desired, a new FSv2 filter should
be defined.
Note-2: Although IPv6 allows for more than one Next Header field in
the packet, the main goal of the Type 3 FSv2 component is to match
the first upper layer protocol value.
4.1.5. Destination Port (type = 5)
IPv4/IPv6 Name: Destination Port (reference: [RFC8955]), [RFC8956])
Filter defines: a list of match filters for destination port for TCP
or UDP within a received packet
Hares, et al. Expires 27 April 2022 [Page 19]
Internet-Draft BGP FlowSpec v2 October 2021
Length: variable
Component Value format: [numeric_op, value]+
4.1.6. Source Port (type = 6)
IPv4/IPv6 Name: Source Port (reference: [RFC8955]), [RFC8956])
Filter defines: a list of match filters for source port for TCP or
UDP within a received packet
IPv4/IPv6 length: variable
IPv4/Ipv6 value: [numeric_op, value]+
4.1.7. ICMP Type (type = 7)
IPv4: ICMP Type : Source Port (reference: [RFC8955])
Filter defines: Defines: a list of match criteria for ICMPv4 type
IPv6: ICMPv6 Type (reference: [RFC8956])
Filter defines: a list of match criteria for ICMPv6 type.
IPv4/IPv6 length: variable
IPv4/IPv6 value: [numeric_op, value]+
4.1.8. ICMP Code (type = 8)
IPv4: ICMP Type : Source Port (reference: [RFC8955])
Filter defines: a list of match criteria for ICMPv4 code.
IPv6: ICMPv6 Type (reference: [RFC8956])
Filter defines: a list of match criteria for ICMPv6 code.
IPv4/IPv6 length: variable
IPv4/IPv6 value: [numeric_op, value]+
Hares, et al. Expires 27 April 2022 [Page 20]
Internet-Draft BGP FlowSpec v2 October 2021
4.1.9. TCP Flags (type = 9)
IPv4/IPv6: TCP Flags Code (reference: [RFC8955])
Filter defines: a list of match criteria for TCP Control bits
IPv4/IPv6 length: variable
IPv4/IPv6 value: [bitmask_op, value]+
Note: a 2 octets bitmask match is always used for TCP-Flags
4.1.10. Packet length (type = 10)
IPv4/IPv6: Packet Length (reference: [RFC8955], [RFC8956])
Filter defines: a list of match criteria for length of packet
(excluding L2 header but including IP header).
IPv4/IPv6 length: variable
IPv4/IPv6 value: [numeric_op, value]+
Note:[RFC8955] uses either 1 or 2 octet values.
4.1.11. DSCP (DiffServe Code Point)(type = 11)
IPv4/IPv6: DSCP Code (reference: [RFC8955], [RFC8956])
Filter defines: a list of match criteria for DSCP code values to
match the 6-bit DSCP field.
IPv4/IPv6 length: variable
IPv4/IPv6 value: [numeric_op, value]+
Note: This component uses the Numeric Operator (numeric_op) described
in [RFC8955] in section 4.2.1.1. Type 11 component values MUST be
encoded as single octet (numeric_op len=00).
The six least significant bits contain the DSCP value. All other
bits SHOULD be treated as 0.
Hares, et al. Expires 27 April 2022 [Page 21]
Internet-Draft BGP FlowSpec v2 October 2021
4.1.12. Fragment (type = 12)
IPv4/IPv6: Fragment (reference: [RFC8955], [RFC8956])
Filter defines: a list of match criteria for specific IP fragments.
Length: variable
Component Value format: [bitmask_op, value]+
Bitmask values are:
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| 0 | 0 | 0 | 0 |lf |FF |IsF| DF|
+---+---+---+---+---+---+---+---+
Figure 6
Where:
DF (don't fragment): match If IP header flags bit 1 (DF) is 1.
IsF(is a fragment other than first: match if IP header fragment
offset is not 0.
FF (First Fragment): Match if [RFC0791] IP Header Fragment offset
is zero and Flags Bit-2 (MF) is 1.
LF (last Fragment): Match if [RFC7091] IP header Fragment is not 0
And Flags bit-2 (MF) is 0
0: must be sent in NLRI encoding as 0, and must be ignored during
reception.
4.1.13. Flow Label(type = 13)
IPv4/IPv6: Fragment (reference: [RFC8956])
Filter defines: a list of match criteria for 20-bit Flow Label in the
IPv6 header field.
Length: variable
Component Value format: [numeric_op, value]+
Hares, et al. Expires 27 April 2022 [Page 22]
Internet-Draft BGP FlowSpec v2 October 2021
4.1.14. Parts of SID (type = 14
IPv6: Service Identifier Matches (reference:
[I-D.ietf-idr-flowspec-srv6]
Filter defines: a list of match bit match criteria for some
combinations of the LOC, FUNCT and ARG in SID fields in the SID or or
whole SID.
Length: variable
Component Value format: [type, LOC-Len, FUNCT-Len, ARG-Len, [op,
value]+]
where:
* type (1 octet): This indicates the new component type (TBD1, which
is to be assigned by IANA).
* LOC-Len (1 octet): This indicates the length in bits of LOC in
SID.
* iFUNCT-Len (1 octet): This indicates the length in bits of FUNCT
in SID.
* ARG-Len (1 octet): This indicates the length in bits of ARG in
SID.
* [op, value]+: This contains a list of {operator, value} pairs that
are used to match some parts of SID.
The total of three lengths (i.e., LOC length + FUNCT length + ARG
length) MUST NOT be greater than 128. If it is greater than 128, an
error occurs and it is treated as a withdrawl [RFC7606] and
[RFC4760].
The operator (op) byte is encoded as:
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| e | a | field type|lt |gt |eq |
+---+---+---+---+---+---+---+---+
Figure 7
where:
Hares, et al. Expires 27 April 2022 [Page 23]
Internet-Draft BGP FlowSpec v2 October 2021
where the behavior of each operator bit has clear similarity with
that of [RFC8955]'s Numeric Operator field.
e (end-of-list bit): Set in the last {op, value} pair in the
sequence.
a - AND bit: If unset, the previous term is logically ORed with
the current one. If set, the operation is a logical AND. It
should be unset in the first operator byte of a sequence. The AND
operator has higher priority than OR for the purposes of
evaluating logical expressions.
field type:
- 000: SID's LOC
- 001: SID's FUNCT
- 010: SID's ARG
- 011: SID's LOC:FUNCT
- 100: SID's FUNCT:ARG
- 101: SID's LOC:FUNCT:ARG
Note: For an unknown field type, Error Handling is to "treat as
withdrawl" [RFC7606] and [RFC4760].
lt: less than comparison between data' and value'.
gt: greater than comparison between data' and value'.
eq: equality between data' and value'.
The data' and value' used in lt, gt and eq are indicated by the field
type in an operator and the value field following the operator.
The value field depends on the field type and has the value of SID's
some parts rounding up to bytes (refer to the table 3 in figure 8
below ).
Hares, et al. Expires 27 April 2022 [Page 24]
Internet-Draft BGP FlowSpec v2 October 2021
Table 3 - SID Parts fields
+-----------------------+------------------------------+
| Field Type | Value |
+=======================+==============================+
| SID's LOC | value of LOC bits |
+-----------------------+------------------------------+
| SID's FUNCT | value of FUNCT bits |
+-----------------------+------------------------------+
| SID's ARG | value of ARG bits |
+-----------------------+------------------------------+
| SID's LOC:FUNCT | value of LOC:FUNCT bits |
+-----------------------+------------------------------+
| SID's FUNCT:ARG | value of FUNCT:ARG bits |
+-----------------------+------------------------------+
| SID's LOC:FUNCT:ARG | value of LOC:FUNCT:ARG bits |
+-----------------------+------------------------------+
Figure 8
4.2. Encoding of Actions (type=2)
The FSv2 actions may be sent in an Extended Community, a Wide
Community or an NLRI.
The Extended Community encodes the Flow Specification actions in the
Extended Community format [RFC4360].
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 high | Type low(*) | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Value (6 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9
The Wide Community definition for FSv2 actions is 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 = 2 | Flags |C|T| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length |<sequence of FSv2-Action-TLV>+ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--------------------------------
Figure 10
Hares, et al. Expires 27 April 2022 [Page 25]
Internet-Draft BGP FlowSpec v2 October 2021
where FSv2-Action-TLV is defined as:
FSv2-Action-TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| action order | Identifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|<action-subTLVs>+ |
+--------------------------------
Figure 11
Where FS-SubTLVs have the format:
FS-SubTLVs
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SubTLV type (2 octet) | length type (2 octet) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| value (variable) |
+-------------------------------+
Figure 12
The FSv2 Action TLV may be included in the NLRI to be associated with
a specific NLRI. (Note inclusion with the FSv2 NLRI does not have
good scaling properties.)
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 = 2 | length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| action-order | chain-ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| length-TLV | value <SubTLVs>+ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13
where:
Hares, et al. Expires 27 April 2022 [Page 26]
Internet-Draft BGP FlowSpec v2 October 2021
action-order: is the user defined action within the list
chain ID: is a 2-byte identifier for action chain
length -TLV - is the length of the TLV
value - contains a sequence of action SubTLVs.
Each Action SubTLV has the format:
+-------------------------------+
| SubTLV type (2 octet) |
+-------------------------------+
| length (2 octet) |
+-------------------------------+
| value (variable) |
+-------------------------------+
Figure 14
Where:
* SubTLV type: values are action type values shown in Table 4 below.
* length: is the length of the action subtlv
* Value is specific to the SubTLV
Hares, et al. Expires 27 April 2022 [Page 27]
Internet-Draft BGP FlowSpec v2 October 2021
Table 4 – FSv2 Action types
Action Description
====== ===========
00 reserved
01 Action Chain Operation
02 traffic actions per interface group
06 traffic rate limited by bytes
07 traffic action (terminal/sample)
08 redirect IPv4
09 mark DSCP value
10 associate L2 Information
11 associate E-Tree Information
12 traffic rate limited by packets
13 redirect to IPv6
14 SFC Classifier Info (moved from OD to OE)
15 redirect to Indirection-id (move from 0x00)
15-21 TBA (to be assigned)
22 VLAN-Action (0x16)[draft-ietf-idr-flowspec-l2vpn-17]
23 TPID-Action (0x17) [draft-ietf-idr-flowspec-l2vpn-17]
24-254 TBA (to be assigned)
255 reserved
Figure 15
Ordering of actions within a rule
The actions are first stored in user-defined order. If multiple
actions exist for a single action order value, then the actions will
be ordered by action type followed by value.
Action specifications must include descriptions of order comparison
for the values within the action.
4.2.1. Action 1 - Action Chain operation (ACO) (0x01)
SubTLV: 0x01
Length: variable
Value:
AC-failure-type - byte that determines the action on failure
AC-failure-value - variable depending on AC-failure-type.
Hares, et al. Expires 27 April 2022 [Page 28]
Internet-Draft BGP FlowSpec v2 October 2021
Actions may succeed or fail and an Action chain must deal with it.
The default value stored for an action chain that does not have this
action chain is "stop on failure".
where:
AC-Failure types are:
- 0x00 - default - stop on failure
- 0x01 - continue on failure (best effort on actions)
- 0x02 - conditional stop on failure - depending on AC-Failure-
value
- 0x03 - rollback - do all or nothing - depending in AC-Failure-
value
AC-Failure values: TBD
Interactions with other actions: Interactions with all other Actions
Ordering within Action type:By AC-Failure type
4.2.2. Traffic Actions per interface set (TAIS) (0x02)
SubTLV: 0x2
Length: 8 octets (6 in extended community)
Value field: [4-octet-AS] [GroupID 2-octet] [action 2-octet]
where:
Group-ID: identifier for group in 2 octets (14 lower bits)
- Note: Extended Community format will have 2 bits for action.
Action: determines inbound or outbound action where:
- Outbound(0x1): FSv2 rule MUST be applied in outbound Direction
to interface set identified by Group-id
- Inbound (0x2): FSv2 rule MUST be applied in inbound Direction
to interface set identified by Group-ID.
Value ordering: AS, then Group ID, then Action bytes.
Hares, et al. Expires 27 April 2022 [Page 29]
Internet-Draft BGP FlowSpec v2 October 2021
Conflict: with any bi-direction action such as
1. traffic rate limited by bytes, or
2. traffic rate limited by packets.
Reference: [I-D.ietf-idr-flowspec-interfaceset]
4.2.3. Traffic rate limited by bytes (TRB) (0x6)
SubTLV:0x6
Length: 8 octets
Value field:[4-octet-AS] [float (4 bytes)]
where:
[4-octet-AS]:4 byte AS number
- If FSv1 passes the lower 2 bytes of 4 byte AS number, use
[TBD5] as higher 2 bytes to identify.
Float: maximum byte rate in IEEE floating point [IEEE.754.19895
format] in units per second.
- A value of 0 should result in all traffic for the particular
flow to be discarded.
Value ordering: AS then float value
Action Conflict: traffic-rate-packets
reference: [RFC8955]
4.2.4. Traffic Action (TA)(0x7)
SubTLV: 0x7
Length: 1
Value field: [1-octet action]
where the traffic action values are:
1 = Terminal flow specification action
2 - Sample - enables sampling and logging
Hares, et al. Expires 27 April 2022 [Page 30]
Internet-Draft BGP FlowSpec v2 October 2021
3 - Terminal action + sample
Value ordering: By traffic action values
Conflicts/Interactions: duplication of packets also occurs in:
Redirect to IPv4 (action 0x08),
Redirect to IPv6 (action 0x0D (13)),
Redirect to SFC (action 0xOE (14))
Redirect to Indirection-ID (action 0xF (15)
4.2.5. Redirect to IPv4 (RDIPv4)[0x8)
SubTLV: 0x08
Length: 12 octets
Value field:
[4-byte-AS] [IPv4 address (4 octets] [ID (4 octets)] [Flag (1 octet)]
where:
4-octet-AS - is a 4-byte AS in a Route Target
IPv4 address - is an IP Address in RT
ID - the 4-octet value set by user
Flag is 1 octet value with the following definitions:
- 0 - reserved
- 1 - copy and redirect copy
Value ordering: 4-octet AS, then IP addres, then ID (lowest to
highest) with:
No AS specified uses AS value of zero.
No IP specified uses IP value of zero.
No ID specified uses ID value of zero.
Hares, et al. Expires 27 April 2022 [Page 31]
Internet-Draft BGP FlowSpec v2 October 2021
Conflicts/Interactions: Any redirection or traffic sampling found in:
Traffic Action (action 0x07),
Redirect to IPv6 (action 0x0D (13)),
Redirect to SFC (action 0xOE (14))
Redirect to Indirection-ID (action 0xF (15)
reference: [RFC8955], draft-ietf-idr-flowspec-ip-02.txt
4.2.6. Traffic marking (TM) (0x9)
SubTLV: 0x9
Length: 1 octet
Value: DSCP field with the 2 left most bits zero
The DSCP field format is:
0 1 2 3 4 5 6 7
+---------------+
|R R DSCP bits |
+---------------+
Figure 16
where:
RR - reserved bits (set to zero to send, ignored upon reception
and set to zero.
DSCP - 6 bits of DSCP values
Ordering within Value: Based on DSCP value
Conflicts: none
reference: [RFC8955]
4.2.7. Traffic rate limited by packets (TRP) (12/0xC)
SubTLV= 12 (0xC)
Length: 8
Hares, et al. Expires 27 April 2022 [Page 32]
Internet-Draft BGP FlowSpec v2 October 2021
Value field: [4-octet-AS] [float (4 octet)]
Where:
4-octet AS - is the AS setting this value
Float - specifies maximum rate [IEEE.754.185] format in packets
per second.
- A traffic rate of zero should result in all packets being
discard. The traffic rate should not be negative.
Ordering within Value: Based on DSCP value
Conflicts: Traffic rate limited by bytes (0x06)
reference: [RFC8955]
4.2.8. Traffic redirect to IPv6 (RDIPv6) (13, 0xD)
SubTLV = 13 (0xD)
Length = 24 octets
Value field: [4-octet-as] [IPv6-address (16 octets)] [local
administrator (2 octets] [Flag (1 octets)]
where:
4-octet-AS - is the AS requesting action in 4 byte AS format,
IPv6-address - is the redirection IPv6 address
Local administrator - 2 bytes assigned by network administrator.
lag (1 octet) with the following definitions:
- 0 - reserved
- 1 - copy and redirect copy
Ordering within Value: AS, then IPv6, the flag (low to high)
Conflicts/Interactions: Any redirection or traffic sampling found in:
Traffic Action (action 0x07) ,
Hares, et al. Expires 27 April 2022 [Page 33]
Internet-Draft BGP FlowSpec v2 October 2021
Redirect to IPv4 (action 0x08 (8)),
Redirect to SFC (action 0xOE (14))
Redirect to Indirection-ID (action 0xF (15)
4.2.9. Traffic insertion in SFC (TISFC)(14, OXE)
SubTLV = (14, 0xE)
Note: replace IANA 0xD FSv1 with FSv2 OxE.
Length = 6 octets
Value field: [SPI (3 octets)][SI (1 octet)][SFT (2 octet)]
where:
SPI - is the service path identifier
SI - is the service index
SFT - is the service function type.
Value ordering: SPI, then SI, then SFT (lowest to highest)
Conflicts/Interactions: Any redirection or traffic sampling found in:
Traffic Action (action 0x07) ,
Redirect to IPv4 (action 0x08 (8)),
Redirect to IPv6 (action 0xOD (13))
Redirect to Indirection-ID (action 0xF (15)
Reference: [RFC9015]
4.2.10. Flow Specification Redirect to Indirection-ID (RDIID) (0x0F)
SubTLV: 15, 0x0F
note: current value is 0x00 for FSv1
Length: 6 octets
Value field:
Hares, et al. Expires 27 April 2022 [Page 34]
Internet-Draft BGP FlowSpec v2 October 2021
[Flags (1 octet)] [ID-Type (1 octet)][Generalized-ID (4 octets)]
where:
Flags: are defined as:
- S-ID]: sequence number for indirection IDs (3 bits).
o Value of zero means sequence is not set and all other S-ID
values should be ignored
- [C] - copy packets matching this ID
ID-Type: type of indirection ID with following values:
- 0 - localized ID
- 1 - Node with SID/index in MPLS SR
- 2 - Node with SID/label in MPLS SR
- 3 - Node with Binding Segment ID with SID/Index
- 4 - Node with Binding Segment ID with SID/Label
- 5 - Tunnel ID
Generalized-ID (G-ID): indirection value
Value Ordering: first indirection ID, then Generalized ID
Action Value ordering: ID-Type by value (lowest to highest)
Conflicts/Interactions: Any redirection or traffic sampling found in:
Traffic Action (action 0x07) ,
Redirect to IPv4 (action 0x08 (8)),
Redirect to IPv6 (action 0x0D, (13)
Redirect to SFC (action 0xOE (14))
reference: [I-D.ietf-idr-flowspec-path-redirect]
Hares, et al. Expires 27 April 2022 [Page 35]
Internet-Draft BGP FlowSpec v2 October 2021
4.2.11. VLAN action (VLAN) (action 0x16, 22)
Function: Rewrite inner or outer VLAN header
SubTLV: 22 (0x16)
Length: 6 octets
Value:
[Rewrite-actions (2 octets)]
[vlan-PCP-DE-1 (2 octets)]
[vlan-PCP-DE-2 [2 octets)]
where:
Rewrite-actions - is as follows:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
|PO1|PU1|SW1|RI1|RO1| Resv |PO2|PU2|SW2|RI2|RO2| Resv |
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
Figure 17
PO1: Pop action. If the PO1 flag is one, it indicates the outmost
VLAN should be removed.
PU1: Push action. If PU1 is one, it indicates VLAN ID1 will be
added, the associated Priority Code Point (PCP and Drop
Eligibility Indicator (DEI) are PCP1 and DE1.
SW1: Swap action. If the SW1 flag is one, it indicates the outer
VLAN and inner VLAN should be swapped.
PO2: Pop action. If the PO2 flag is one, it indicates the outmost
VLAN should be removed.
PU2: Push action. If PU2 is one, it indicates VLAN ID2 will be
added, the associated PCP and DEI are PCP2 and DE2.
SW2: Swap action. If the SW2 flag is one, it indicates the outer
VLAN and inner VLAN should be swapped.
Hares, et al. Expires 27 April 2022 [Page 36]
Internet-Draft BGP FlowSpec v2 October 2021
RI1 and RI2: Rewrite inner VLAN action. If the RIx flag is one
where "x" is "1" or "2"), it indicates the inner VLAN should be
replaced by a new VLAN where the new VLAN is VLAN IDx and the
associated PCP and DEI are PCPx and DEx. If the VLAN IDx is 0,
the action is to only modify the PCP and DEI value of the inner
VLAN.
RO1 and RO2: Rewrite outer VLAN action. If the ROx flag is one
(where "x" is "1" or "2"), it indicates the outer VLAN should be
replaced by a new VLAN where the new VLAN is VLAN IDx and the
associated PCP and DEI are PCPx and DEx. If the VLAN IDx is 0,
the action is to only modify the PCP and DEI value of the outer
VLAN.
Resv: Reserved for future use. MUST be sent as zero and ignored
on receipt.
Value ordering: rewrite-actions, VLAN1, VLAN2, PCP-DE1, PCP-DE2
Conflicts: TIPD Action
reference: [I-D.ietf-idr-flowspec-l2vpn]
4.2.12. TPID action (TPID) (action 0x17, 23)
Function: Replace Inner or outer TP
SubTLV: 23 (0x17)
Length: 6 octets
Value:
[Rewrite-actions (2 octets)]
[TP-ID-1 (2 octets)]
[TP-ID-2 (2 octets)]
Where: rewrite-actions are bitmask (2 octets) with 2 actions as
follows:
0 15
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|TI|TO| Resv |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Figure 18
Hares, et al. Expires 27 April 2022 [Page 37]
Internet-Draft BGP FlowSpec v2 October 2021
TI: Mapping inner Tag Protocol (TP) ID (typically a VLAN) action. If
the TI flag is one, it indicates the inner TP ID should be replaced
by a new TP ID, the new TP ID is TP ID1.
TO: Mapping outer TP ID action. If the TO flag is one, it indicates
the outer TP ID should be replaced by a new TP ID, the new TP ID is
TP ID2.
Resv: Reserved for future use. MUST be sent as zero and ignored on
receipt
Value Ordering: rewrite-actions, TP-ID-1, TP-ID-2
Conflicts: VLAN action
reference:[I-D.ietf-idr-flowspec-l2vpn]
4.2.13. Extended Community vs. Action SubTLV formats
The SubTLV format is used for the Wide communities and for the action
subTLVs in the NLRI.
Sub-TLV Action Action SubTLV Extended Community
type Name format format
======= ===== =============== ====================
1 ACO type: 1 not applicable (n/a)
length:variable
2 TAIS type: 2 type: 0x0702 or 0x4702
length:8 length: 6
[4-octet-as] [4-octet-AS]
[group-3-octet] [flags-group] (2)
[flags-1-octet]
3-5 reserved
Sub-TLV Action Action SubTLV Extended Community
type Name format format
======= ===== =============== ====================
6 TRB type:6 type:8006
length:8 length: 6
[4-byte-AS] [2-byte-AS]
[float (4 octets)] [float (4 octets)]
Hares, et al. Expires 27 April 2022 [Page 38]
Internet-Draft BGP FlowSpec v2 October 2021
7 TA type:7 type:8007
length:1 length:6 octets
flags: (1 octet) flags (6 octets)
8 RDIPv4 type:8 type:8008
length: 12 length: 6 octets
[4-byte-AS] [AS-2-octets]
[IPv4-address] [IPv4 address]
type:8108
length: 6 octets
[IPv4 address]
[ID-2 octets]
type:8208
length: 6 octets
[AS-4-octets]
[ID-2-octets]
9 TM type:9 type:8009
length:1 length:6
DSCP: 1 octet DSCP: 1 octet
10-11 reserved
12 TRP type:12 (0xC) type: 0x800C
length: 8 octets length: 6 octets
[4-byte-AS] [2-byte-AS]
[float-4-octet] [float-4-octet]
13 RDIPv6 type:13 (0xD) type:0x000C
length:22 length: 18
[4-byte-AS] [IPv6-address (16)]
[IPv6-address (16)] [local-admin (2)]
[local-admin (2)]
Sub-TLV Action Action SubTLV Extended Community
type Name format format
======= ===== =============== ====================
14 TISFC type:14 (0xE) type: 0xD (FSv1)
type: 0xE (FSv2)
Hares, et al. Expires 27 April 2022 [Page 39]
Internet-Draft BGP FlowSpec v2 October 2021
length:6 length:6
SPI (3 octets) SPI (3 octets)
SI (1 octet) SI (1 octet)
SFT (2 octets) SFT (2 octets)
15 RDIID type:15 (0xF) Type: 0900 (FSv1)
length: 6 length 6
flags (1) flags (1)
ID-type (1) ID type (1)
G-ID (4 octets) G-ID (4-octets)
16-21 reserved
22 VLAN type:22 (0x16) Type: (TBD)
length:6 length:6
[rewrite-action(2)] [rewrite-actions (2)]
[vlan-pcp-de-1 (2)] [vlan-pcp-de-1 (2)]
[vlan-pcp-de-2 (2)] [vlan-pcp-de-2 (2)]
23 TPID type:23 (0x17) Type: (TBD)
length:6 length:6
[rewrite-action(2)] [rewrite-actions (2)]
[TP-ID-1 (2)] [TP-ID-1 (2)]
[TP-ID-2 (2)] [TP-ID-2 (2)]
4.3. L2 and L2VPN FSv2 Filters
field includes the AFI (2 octets), SAFI (1 octet) and will be 6/TBD1
or, for the VPN case, 28/TBD2
Hares, et al. Expires 27 April 2022 [Page 40]
Internet-Draft BGP FlowSpec v2 October 2021
+-------------------------------+
| +--------------------------+ |
| | L3 AFI-SAFI field (3) | |
| | <subTLVs>+ | |
| +==========================+ |
+-------------------------------+
Each SubTLV has the format:
+-------------------------------+
| SubTLV type (1 octet) |
+-------------------------------+
| length (1 octet) |
+ ------------------------------+
| value (variable) |
+-------------------------------+
Figure 19
SubTLV type: A component type value defined in the "L2 Flow
Specification Component Types" registry for L2 by [draft-ietf-idr-
flowspec-l2vpn).
Where the SubTLVs have the following component types:
Component Types Table
Component
type Description
======= ==================
1 EtherType
2 Source MAC
3 Destination MAC
4 DSAP (destination service access point)
5 SSAP (source service access point)
6 control field in LLC
7 SNAP
8 VLAN ID
9 VPAN PCP
10 Inner VLAN ID
11 Inner VLAN PCP
12 VLAN DEI
13 VLAN DEI
14 Source MAC special bits
15 Destination MAC special bits
Table 4 – L2 VPN components
Hares, et al. Expires 27 April 2022 [Page 41]
Internet-Draft BGP FlowSpec v2 October 2021
See [I-D.ietf-idr-flowspec-l2vpn] for the details on the format and
value fields for each component.
Value ordering: Ordering of L2 FSv2 rules will be by user-defined
order of the rule. For FSv2 filters within the same rule, the
ordering will be by component number and then by value within the
component. See [I-D.ietf-idr-flowspec-l2vpn] for the ordering of the
values within the component.
reference: [I-D.ietf-idr-flowspec-l2vpn]
4.4. FSv2 SFC NLRI Traffic Filters
The FSv2 filters allow for filtering of the SFC NLRI family of
routes. The traffic NLRIs filtered are from SFC AFI/SAFI (AFI = 31,
SAFI=9).
The FSv2 filters provide this filtering with SFC AFI (AFI=31) and
SAFI for FSv2 filters (SAFI = TB1).
+--------------------------------------+
| +---------------------------------+ |
| | Tunneled AFI/SAFI field | |
| | <subTLVs>+ | |
| +=================================+ |
+--------------------------------------+
Figure 20
Each SubTLV has the format:
+-------------------------------+
| SubTLV type (1 octet) |
+-------------------------------+
| length (1 octet) |
+ ------------------------------+
| value (variable) |
+-------------------------------+
Figure 21 – Tunneled SubTLV format
The components listed are:
Hares, et al. Expires 27 April 2022 [Page 42]
Internet-Draft BGP FlowSpec v2 October 2021
1 = SFIR RD Type (types 1, 2, 3)
2 = SFIR RD Value
3 = SFIR Pool ID
4 = SFIR MPLS context/label
5 = SFPR SPI
6 = SPF attribute fields
Table 6 – SFC Filter types
Ordering is by: User-defined rule order, component number, and then
value within component.
reference: [RFC9015], [TBD]
4.5. Encoding of Actions passed in Wide Communities
The BGP Flow specification version 2 actions are passed in a Wide
Community [I-D.ietf-idr-wide-bgp-communities] atom with the following
format:
+----------------------------+
| atom-id |
+----------------------------+
| length (2 octets) |
+----------------------------+
| <Action-Sub-TLVs>+ |
+----------------------------+
Figure 22 - Flow Specification with
IDs for Wide Community Actions
where:
Atom-id (TBD) - is id to be defined
length: variable depending on SubTLVS
Action Sub-TLVs as defined above
The BGP Flow Specification (BGP-FS) atom can be part of the Wide
Community container (type 1) or the BGP Flow Specification Atom can
be part of the BGP Flow Specification container (type 2) which will
have:
Hares, et al. Expires 27 April 2022 [Page 43]
Internet-Draft BGP FlowSpec v2 October 2021
+-----------------------------+
| Source AS Number (4 octets)|
+-----------------------------+
| list of atoms (variable) |
+-----------------------------+
Figure 23: Atom format
5. Validation of FSv2 NLRI
The validation of FSv2 NLRI adheres to the combination of rules for
general BGP FSv1 NLRI found in [RFC8955], [RFC8956], [RFC9117], and
the specific additions made for SFC NLRI [RFC9015], L2VPN NLRI
[I-D.ietf-idr-flowspec-l2vpn].
To provide clarity, the full validation process for flow
specification routes (FSv1 or FSv2) is described in this section
rather than simply refer to the portions of these RFCs. Validation
only occurs after BGP UPDATE packet, the FSv2 NLRI and the path
attributes relating to FSv2 (Extended community and Wide Community)
have been determined to be well-formed. Any MALFORMED FSv2 NRLI is
handled as a "TREAT as WITHDRAW".
5.1. Validation of FS NLRI (FSv1 or FSv2)
Flow specification received from a BGP peer that are accepted in the
respective Adj-RIB-In are used as input to the route selection
process. Although the forwarding attributes of the two routes for
same prefix may be the same, BGP is still required to perform its
path selection algorithm in order to select the correct set of
attributes to advertise.
The first step of the BGP Route selection procedure (section 9.1.2 of
[RFC4271] is to exclude from the selection procedure routes that are
considered unfeasible. In the context of IP routing information,
this is used to validate that the NEXT_HOP Attribute of a given route
is resolvable.
The concept can be extended in the case of the Flow Specification
NLRI to allow other validation procedures.
The FSv2 validation process validates the FSv2 NLRI with following
unicast routes received over the same AFI (1 or 2) but different
SAFIs:
* Flow specification routes (FSv1 or FSv2) received over SAFI=133
will be validated against SAFI=1,
Hares, et al. Expires 27 April 2022 [Page 44]
Internet-Draft BGP FlowSpec v2 October 2021
* Flow Specification routes (FSv1 or FSv2) received over SAFI=134
will be validated against SAFI=128, and
* Flow Specification routes (FSv1 or FSv2) [AFI =1, 2] received over
SAFI=77 will be validated will be validated using only the Outer
Flow Spec against SAFI = 133.
The FSv2 validates L2 FSv2 NLRI with the following L2 routes received
over the same AFI (25), but a different SAFI:
* Flow specification routes (FSv1 or FSv2)received over SAFI=135 are
validated against SAFI=128.
In the absence of explicit configuration, a Flow specification NLRI
(FSv1 or FSv2) MUST be validated such that it is considered feasible
if and only if all of the conditions are true:
a) A destination prefix component is embedded in the Flow
Specification,
b) One of the following conditions must hold true:
- 1. The originator of the Flow Specification matches the
originator of the best-math unicast route for the destination
prefix embedded in the flow specification (this is the unicast
route with the longest possible prefix length covering the
destination prefix embedded in the flow specification).
- 2. The AS_PATH attribute of the flow specification is empty or
contains only an AS_CONFED_SEQUENCE segment [RFC5065].
o 1.This condition should be enabled by default.
o 2.This condition may be disabled by explicit configuration
on a BGP Speaker,
o 3.As an extension to this rule, a given non-empty AS_PATH
(besides AS_CONFED_SEQUENCE segments) MAY be permitted by
policy].
c) There are no "more-specific" unicast routes when compared with
the flow destination prefix that have been received from a
different neighbor AS than the best-match unicast route, which has
been determined in rule b.
However, rule a may be relaxed by explicit configuration, permitting
Flow Specifications that include no destination prefix component. If
such is the case, rules b and c are moot and MUST be disregarded.
Hares, et al. Expires 27 April 2022 [Page 45]
Internet-Draft BGP FlowSpec v2 October 2021
By "originator" of a BGP route, we mean either the address of the
originator in the ORIGINATOR_ID Attribute [RFC4456] or the source
address of the BGP peer, if this path attribute is not present.
BGP implementation MUST enforce that the AS in the left-most position
of the AS_PATH attribute of a Flow Specification Route (FSv1 or FSv2)
received via the Exterior Border Gateway Protocol (eBGP) matches the
AS in the left-most position of the AS_PATH attribute of the best-
match unicast route for the destination prefix embedded in the Flow
Specification (FSv1 or FSv2) NLRI.
The best-match unicast route may change over time independently of
the Flow Specification NLRI (FSv1 or FSv2). Therefore, a
revalidation of the Flow Specification MUST be performed whenever
unicast routes change. Revalidation is defined as retesting rules a
to c as described above.
5.2. Validation of Flow Specification Actions
Flow Specification may be mapped using Extended Communities, Wide
Communities or a FSv2 NLRI TLV. The scaling of FSv2 actions implies
that Extended Communities and wide communities which can associate an
action to a large number of NLRIs will be most often used.
Therefore, it is likely the FSv2 NLRI TLV for actions will be very
few actions (such as the "die-die-die Internet worm" use case).
The ordering of precedence for these actions in the absence of user-
defined ordering, is to follow the precedence of the FSv2 NLRI action
TLV values (lowest to highest). If multiple items exist for the same
action type, then ordering is described within each Action SubTLV.
Extended Community actions should be translated to the Action SubTLV
format for internal comparison.
Actions may conflict, duplicate, or complementation other actions.
An example of conflict is the packet rate limiting by byte and by
packet. An example of a duplicate is the request to copy or sample a
packet under one of hte redirect functions (RDIPv4, RDIPv6, RDIID, )
Each FSv2 actions in this document defines the potential conflicts or
duplications. Specifications for new FSv2 actions outside of this
specification MUST specify interactions or conflicts with any FSv2
actions (in this specification or subsequent specification).
Well-formed syntactically correct actions should be linked to a
filtering rule in order the actions should be enacted. If one action
in the ordered list fails, the default procedure is for the action
process for this rule to stop and flag the error via system
management. By explicit configuration, the action processing may
continue after errors..
Hares, et al. Expires 27 April 2022 [Page 46]
Internet-Draft BGP FlowSpec v2 October 2021
Implementations MAY wish to log the actions taken by FS actions (FSv1
or FSv2).
5.3. Error handling and Validation
The following two error handling rules must be followed by all BGP
speakers which support FSv2:
* FSv2 NLRI having TLVs which do not have the correct lengths or
syntax must be considered MALFORMED.
* FSv2 NLRIs having TLVs which do not follow the above ordering
rules described in section 4.1 MUST be considered as malformed by
a BGP FSv2 propagator.
The above two rules prevent any ambiguity that arises from the
multiple copies of the same NLRI from multiple BGP FSv2 propagators.
A BGP implementation SHOULD treat such malformed NLRIs as 'Treat-as-
withdraw'.
An implementation for a BGP speaker supporting both FSv1 and FSv2
must support the error handling for both FSv1 and FSv2. The storage
of the BGP FSv1 and FSv2 must support both the AFI/SAFI and the
configuration which translates FSv1 NLRI into FSv2 NLRI for order
storage.
6. Ordering for Flow Specification v2 (FS-v2)
Flow Specification v2 allows the user to order flow specification
rules and the actions associated with a rule. Each FSv2 rule has one
or more match conditions and one or more actions associated with each
rule.
This section describes how to order FSv2 filters received from a peer
prior to transmission to another peer. The same ordering should be
used for the ordering of forwarding filtering installed based on only
FSv2 filters.
Section 7.0 describes how a BGP peer that supports FSv1 and FSv2
should order order the flow specification filters during the
installation of these flow specification filters into FIBs or
firewall engines in routers.
Hares, et al. Expires 27 April 2022 [Page 47]
Internet-Draft BGP FlowSpec v2 October 2021
The BGP distribution of FSv1 NLRI and FSv2 NLRI and their associated
path attributes for actions (Wide Communities and Extended
Communities) is "ships-in-the-night" forwarding of different AFI/SAFI
information. This recommended ordering provides for deterministic
ordering of filters sent by the BGP distribution.
6.1. Ordering of FSv2 NLRI Filters
The basic principles regarding ordering of rules are simple:
1) Rule-0 (zero) is defined to be 0/0 with the "permit-all" action
- BGP peers which do not support flow specification permit
traffic for routes received. Rule-0 is defined to be "permit-
all" for 0/0 which is the normal case for filtering for routes
received by BGP.
- By configuration option, the "permit-all" may be set to "deny-
all" if traffic rules on routers used as BGP must have a
"route" AND a firewall filter to allow traffic flow.
2)FSv2 rules are ordered based on the user-defined order numbers
specified in the FSv2 NLRI (rules 1-n).
3) If multiple FSv2 NLRI have the same user-defined order, then
the filters are ordered by type of FSv2 NRLI filters (see Table 1,
section 4) with lowest numerical number have the best precedence.
- For the same user-defined order and the same value for the FSv2
filters type, then the filters are ordered by FSv2 the
component type for that FSv2 filter type (see Tables 3-6) with
the lowest number having the best precedence.
- For the same user-defined order, the same value of FSv2 Filter
Type, and the same value for the component type, then the
filters are ordered by value within the component type. Each
component type defines value ordering.
- For component types inherited from the FSv1 component types,
there are the following two types of comparisons:
o FSv1 component value comparison for the IP prefix values,
compares the length of the two prefixes. If the length is
different, the longer prefix has precedence. If the length
is the same, the lower IP number has precedence.
Hares, et al. Expires 27 April 2022 [Page 48]
Internet-Draft BGP FlowSpec v2 October 2021
o For all other FSv1 component types, unless specified, the
component data is compared using the memcmp() function
defined by [ISO_IEC_9899]. For strings with the same
length, the lowest string memcmp() value has precedence.
For strings of different lengths, the common prefix is
compared. If the common string prefix is not equal, then
the string with the lowest string prefix has higher
precedence. If the common prefix is equal, the longest
string is considered to have higher precedence
Notes:
* Since the user can define rules that re-order these value
comparisons, this order is arbitrary and set to provide a
deterministic default.
6.2. Ordering of the Actions
The FSv2 specification allows for actions to be associated by:
a) a Wide Community path attribute,
b) an Extended Community path attribute, and
c) a FSv2 Action TLV in an FSv2 NLRI (poor scaling)
Actions may be ordered by user-defined action order number from 1-n
(where n is 2**16-2 and value of 2**16-1 is reserved.
Extended community actions are associated with order number 32768
[0x8000] or a specific configured value for the FSv2 domain.
Action user-order number zero is defined to have an Action type of
"Set Action Chain operation" (ACO) (value 0x01) that defines the
default action chain process. For details on "set action chain
operation" see section 4.2.0 and section 6.2.1 below.
If the user-defined action number for an action is the same, then the
actions are ordered by FSv2 action types (see Table 3 for a list of
action types). If the user-defined action number and the FSv2 action
types are the same, then the order must be defined by the FSv2
action.
Hares, et al. Expires 27 April 2022 [Page 49]
Internet-Draft BGP FlowSpec v2 October 2021
6.2.1. Action Chain Operation
The "Action Chain Operation" (ACO) changes the way the actions after
this action in an action chain handles a failure. If no action chain
operations are set, then the default action of "stop upon failure"
(value 0x00) will be used for the chain.
An example may help illustrate how failure impacts an action chain.
Suppose we have the following 4 actions defined for a match:
* Sent Redirect to indirection ID (0x01) with user-defined match 2
attached in wide community,
* Traffic rate limit by bytes (0x07) with user-defined match 1
attached in wide community,
* Traffic sample (0x07) sent in extended community, and
* SF classifier Info (0x0E) sent in extended community.
These 4 filters rate limit a potential DDoS attack by: a) redirect
the packet to indirection ID (for slower speed processing), sample to
local hardware, and forward the attack traffic via a SFC to a data
collection box.
The FSv2 action list for the match would look like this
Action 0: Operation of action chain (0x01) (stop upon failure)
Action 1: Traffic Rate limit by byte (0x07)
Action 2: Redirect to Redirection ID (0x0F)
Action 32768 (0x8000) Traffic Action (0x07) Sample
Action 32768 (0x8000) SFC Classifier: (0xE)
If the redirect to a redirection ID fails, then Traffic Sample and
sending the data to an SFC classifier for forwarding via SFC will not
happen. The traffic is limited, but not redirect away from the
network and a sample sent to DDOS processing via a SFC classifier.
Suppose the following 5 actions were defined for a FSV2 filter:
* Set Action Chain Operation (ACO) (0x01) to continue on failure
(ox01) at user-order 2 attached in wide community,
Hares, et al. Expires 27 April 2022 [Page 50]
Internet-Draft BGP FlowSpec v2 October 2021
* redirect to indirection ID (0x0F) at user-order 2 attached in wide
community,
* traffic rate limit by bytes (0x07)with user-order 1 attached in
wide community,
* Traffic sample (0x07) attached via extended community, and
* SFC classifier Info (0x0E) attached in extended community.
The FSv2 action list for the match would look like this:
Action 0: Operation of action chain (0x01) (stop upon failure)
Action 01:Traffic Rate limit by byte (0x07)
Action 02:Set Action Chain Operation (ACO) (0x01) (continue on
failure)
Action 02: Redirect to Redirection ID (0F)
Action 32768 (0x8000): Traffic Action (0x07) Sample
Action 32768 (0x8000): SFC classifier (0x0E) forward via SFC [to
DDoS classifier]
If the redirect to a redirection ID fails, the action chain will
continue on to sample the data and enact SFC classifier actions.
Note:The scaling for associating actions is better with Wide or
Extended Communities which can be associated with many FSv2 filters.
The FSv2 action with FSv2 NLRI should be used in rare cases such the
use case of an pernicious Internet worm. In this case, Suppose we
call the filter "Internet worm" particular filter match identifies
the pernicious Internet worm that must be die off and not be
forwarded. Let us call the actions in the action chain "Die-Die-
Internet-worm". For such a use case, the the FSV2 actions to stop
the packets are tied to the filter even though it may not scale or
have issues in some deployments.
6.2.2. Summary of FSv2 ordering
Operators should use user-defined ordering to clearly specify the
actions desired upon a match. The FSv2 actions default ordering is
specified to provide deterministic order for actions which have the
same user-defined order and same type.
Hares, et al. Expires 27 April 2022 [Page 51]
Internet-Draft BGP FlowSpec v2 October 2021
FS Action Value Order
(lowest value to highest) (lowest to highest)
============================= =================================
0x01: Action chain operation Failure flag
0x02: traffic actions per AS, then Group-ID, then Action ID
Interface group
0x03-0x05 to be assigned TBD
0x06: Traffic rate limit AS, then float value
0x07 – Traffic Action traffic Action value
0x08 – Redirect to IP AS, then IP Address, then ID
0x09 – Traffic Marking DSCP value (lowest to highest)
0x0C – Redirect to Indirect ID AS, then Float value
0x0D – Traffic Redirect to IPv6 AS, IPv6 value, then local Admin
0x0E – Traffic insertion to SFC SPI, then SI, the SFT
0xOF – Redirect to
Indirection-ID ID-type, then Generalized-ID
0x10-0x15 – to be assigned TBD
0x16 – VLAN action rewrite-actions, VALN1, VLAN2,
PCP-DE1, PCP-DE2
0x17 – TPID action rewrite actions, TP-ID-1, TP-ID-2
Figure 24
7. Ordering of FS filters for BGP Peers support FSv1 and FSv2
FSv2 allows the user to order flow specification rules and the
actions associated with a rule. Each FSv2 rule has one or more match
conditions and one or more actions associated with each rule.
Some BGP peers will support FSv1 and FSv2. This section describes
the best practice for ordering the FSv1 and FSv2 filter rules.
One simple rule captures the best practice: Order the FSv1 filters
after the FSv2 filter by placing the FSv1 filters after the FSv2
filters.
To operationally make this work, all flow specification filters
should be included the same data base with the FSv1 filters being
assigned a user- defined order beyond the normal size of FSv2 user-
ordered values.
Suppose you might have 10,000 rules for the FSv2 filters. Assign all
the FSv1 user defined rules to 10,001 (or better yet 20,000). The
FSv1 rules will be ordered by the components and component values.
Hares, et al. Expires 27 April 2022 [Page 52]
Internet-Draft BGP FlowSpec v2 October 2021
All FSv1 actions are defined ordered actions in FSv2. Translate your
FSv1 actions into FSv2 ordered actions for storing in a common
FSv1-FSv2 flow specification data base.
8. Scalability and Aspirations for FSv2
Operational issues drive the deployment of BGP flow specification as
a quick and scalable way to distribute filters. The early operations
accepted the fact validation of the distribution of filter needed to
be done outside of the BGP distribution mechanism. Other mechanisms
(NETCONF/RESTCONF or PCEP) have reply-request protocols.
These features within BGP have not changed. BGP still does not have
an action-reply feature.
NETCONF/RESTCONF latest enhancements provide action/response features
which scale. The combination of a quick distribution of filters via
BGP and a long-term action in NETCONF/RESTCONF that ask for reporting
of the installation of FSv2 filters may provide the best scalability.
The combination of NETCONF/RESTCONF NM protocols and BGP focuses each
protocol on the strengths of scalability.
FSv2 will be deployed in webs of BGP peers which have some BGP peers
passing FSv1, some BGP peers passing FSv2, some BGP peers passing
FSv1 and FSv2, and some BGP peers not passing any routes.
The TLV encoding and deterministic behaviors of FSv2 will not
deprecate the need for careful design of the distribution of flow
specification filters in this mixed environment. The needs of
networks for flow specification are different depending on the
network topology and the deployment technology for BGP peers sending
flow specification.
Suppose we have a centralized RR connected to DDoS processing sending
out flow specification to a second tier of RR who distribute the
information to targeted nodes. This type of distribution has one set
of needs for FSv2 and the transition from FSv1 to FSv2
Suppose we have Data Center with a 3-tier backbone trying to
distribute DDoS or other filters from the spine to combinational
nodes, to the leaf BGP nodes. The BGP peers may use RR or normal BGP
distribution. This deployment has another set of needs for FSv2 and
the transition from FSv1 to FSV2.
Suppose we have a corporate network with a few AS sending DDoS
filters using basic BGP from a variety of sites. Perhaps the
corporate network will be satisfied with FSv1 for a long time.
Hares, et al. Expires 27 April 2022 [Page 53]
Internet-Draft BGP FlowSpec v2 October 2021
These examples are given to indicate that BGP FSv2 like so many BGP
protocols needs to be carefully tuned to aid the mitigation services
within the network. This protocol suite starts the migration toward
better tools using FSv2, but it does not end it. With FSv2 TLVs and
deterministic actions, new operational mechanisms can start to be
understood and utilized.
This FSv2 specification is merely the start of a revolution of work -
not the end.
9. Optional Security Additions
This section discusses the optional BGP Security additions for BGP-FS
v2 relating to BGPSEC [RFC8205] and ROA.
9.1. BGP FS v2 and BGPSEC
Flow specification v1 ([RFC8955] and [RFC8956]) do not comment on how
BGP Flow specifications to be passed BGPSEC [RFC8205] BGP Flow
Specification v2 can be passed in BGPSEC, but it is not required.
FSv1 and FSv2 may be sent via BGPSEC.
9.2. BGP FS v2 with with ROA
BGP Flow Specification v2 can utilize ROAs in the validation. If
BGP-FS v2 is used with BGPSEC and ROA, the first thing is to validate
the route within BGPSEC and second to utilize BGP ROA to validate the
route origin.
The BGP-FS peers using both ROA and BGP-FS validation determine that
a BGP Flow specification is valid if and only if one of the following
cases:
* If the BGP Flow Specification NLRI has a IPv4 or IPv6 address in
destination address match filter and the following is true:
- A BGP ROA has been received to validate the originator, and
- the route is the best-match unicast route for the destination
prefix embedded in the match filter; or
* If a BGP ROA has not been received that matches the IPv4 or IPv6
destination address in the destination filter, the match filter
must abide by the [RFC8955] and [RFC8956] validation rules of:
Hares, et al. Expires 27 April 2022 [Page 54]
Internet-Draft BGP FlowSpec v2 October 2021
- The originator match of the flow specification matches the
originator of the best-match unicast route for the destination
prefix filter embedded in the flow specification", and
- No more specific unicast routes exist when compared with the
flow destination prefix that have been received from a
different neighboring AS than the best-match unicast route,
which has been determined in step A.
The best match is defined to be the longest-match NLRI with the
highest preference.
10. IANA Considerations
This section complies with [RFC7153]
10.1. Flow Specification V2 SAFIs
IANA is required to assign two SAFI Values from the registry at
https://www.iana.org/assignments/safi-namespace from the Standard
Action Range as follows:
Value Description Reference
----- ------------- ---------------
TBD1 BGP-FS V2 [This document]
TBD2 BGP-FS V2 VPN [this document]
10.2. BGP Capability Code
IANA is requested to assign a Capability Code from the registry at
https://www.iana.org/assignments/capability-codes/ from the IETF
Review range as follows:
Value Description Reference Controller
----- --------------------- --------------- ----------
TBD3 Flow Specification V2 [this document] IETF
10.3. Filter IP Component types
IANA is requested to indicate [this draft] as a reference on the
following assignments in the Flow Specification Component Types
Registry:
Hares, et al. Expires 27 April 2022 [Page 55]
Internet-Draft BGP FlowSpec v2 October 2021
Value Description Reference
----- -------------------- ------------------------
1 Destination filter [RFC8955][RFC8956][this draft]
2 Source Prefix [RFC8955][RFC8956][this draft]
3 IP Protocol [RFC8955][RFC8956][this draft]
4 Port [RFC8955][RFC8956][this draft]
5 Destination Port [RFC8955][RFC8956][this draft]
6 Source Port [RFC8955][RFC8956][this draft]
7 ICMP Type [v4 or v6] [RFC8955][RFC8956][this draft]
8 ICMP Code [v4 or v6] [RFC8955][RFC8956][this draft]
9 TCP Flags [v4] [RFC8955][RFC8956][this draft]
10 Packet Length [RFC8955][RFC8956][this draft]
11 DSCP marking [RFC8955][RFC8956][this draft]
12 Fragment [RFC8955][RFC8956][This draft]
13 Flow Label [RFC8956] [This draft]
14 Partial SID {draft-ietf-idr-flowspec-srv6]
[This draft]
10.4. Filter IP component types
IANA is requested to create the following two new registries on a new
"Flow Specification v2 TLV types".
Name: BGP FSv2 TLV types
Reference: [this document]
Registration Procedures: 0x01-0x3FFF Standards Action.
Type Use Reference
----- --------------- ---------------
0x00 Reserved [this document]
0x01 IP traffic rules [this document]
0x02 FSv2 Actions [this document]
0x03 L2 traffic rules [this document]
0x04 tunnel traffic rules [this document]
0x05 SFC AFI filter rules [this document]
0x06-0x3FFF Unassigned [this document]
0x4000-0x7FFF Vendor specific [this document]
0x8000-
0xFFFFFFFF Reserved [this document]
Hares, et al. Expires 27 April 2022 [Page 56]
Internet-Draft BGP FlowSpec v2 October 2021
Name: BGP FSv2 Action types
Reference: [this document]
Registration Procedure: 0x01-0x3FFF Standards Action.
Type Use Reference
----- --------------- ---------------
0x00 Reserved [this document]
0x01 Action Chain Operation (ACO) [this document]
0x02 Traffic actions per
interface group [this document]
0x03 Unassigned [this document]
0x04 Unassigned [this document]
0x05 Unassigned [this document]
0x06 traffic rate limited by bytes [this document]
0x07 traffic action (terminal/sample)[this document]
0x08 redirect IPv4 [this document]
0x09 mark DSCP value [this document]
0x0a associate L2 Information [this document]
0x0b associate E-Tree Information [this document]
0xoc traffic rate limited by packets [this document]
0x0D Redirect to IPv6 [this document]
0x0E Traffic insertion to SFC [this document]
0x0F Redirect to indirection-iD [this document]
0x10 unassigned [this document]
0x11 unassigned [this document]
0x12 unassigned [this document]
0x13 unassigned [this document]
0x14 unassigned [this document]
0x15 unassigned [this document]
0x16 VLAN action [this document]
0x17 TIPD action [this document]
0x18-
0x3ff Unassigned [this document]
0x4000-
0x7fff Vendor assigned [this document]
0xc800-
0xFFFFFFFFF [this document]
11. Security Considerations
The use of ROA improves on [RFC8955] by checking to see of the route
origination. This check can improve the validation sequence for a
multiple-AS environment.
>The use of BGPSEC [RFC8205] to secure the packet can increase
security of BGP flow specification information sent in the packet.
Hares, et al. Expires 27 April 2022 [Page 57]
Internet-Draft BGP FlowSpec v2 October 2021
The use of the reduced validation within an AS [RFC9117] can provide
adequate validation for distribution of flow specification within an
single autonomous system for prevention of DDOS.
Distribution of flow filters may provide insight into traffic being
sent within an AS, but this information should be composite
information that does not reveal the traffic patterns of individuals.
12. References
12.1. Normative References
[I-D.ietf-idr-flowspec-interfaceset]
Litkowski, S., Simpson, A., Patel, K., Haas, J., and L.
Yong, "Applying BGP flowspec rules on a specific interface
set", Work in Progress, Internet-Draft, draft-ietf-idr-
flowspec-interfaceset-05, 18 November 2019,
<https://www.ietf.org/archive/id/draft-ietf-idr-flowspec-
interfaceset-05.txt>.
[I-D.ietf-idr-flowspec-l2vpn]
Hao, W., Eastlake, D. E., Litkowski, S., and S. Zhuang,
"BGP Dissemination of L2 Flow Specification Rules", Work
in Progress, Internet-Draft, draft-ietf-idr-flowspec-
l2vpn-17, 12 May 2021, <https://www.ietf.org/archive/id/
draft-ietf-idr-flowspec-l2vpn-17.txt>.
[I-D.ietf-idr-flowspec-nvo3]
Eastlake, D., Weiguo, H., Zhuang, S., Li, Z., and R. Gu,
"BGP Dissemination of Flow Specification Rules for
Tunneled Traffic", Work in Progress, Internet-Draft,
draft-ietf-idr-flowspec-nvo3-14, 15 August 2021,
<https://www.ietf.org/internet-drafts/draft-ietf-idr-
flowspec-nvo3-14.txt>.
[I-D.ietf-idr-flowspec-path-redirect]
Velde, G. V. D., Patel, K., and Z. Li, "Flowspec
Indirection-id Redirect", Work in Progress, Internet-
Draft, draft-ietf-idr-flowspec-path-redirect-11, 26 May
2020, <https://www.ietf.org/archive/id/draft-ietf-idr-
flowspec-path-redirect-11.txt>.
Hares, et al. Expires 27 April 2022 [Page 58]
Internet-Draft BGP FlowSpec v2 October 2021
[I-D.ietf-idr-flowspec-srv6]
Li, Z., Li, L., Chen, H., Loibl, C., Mishra, G. S., Fan,
Y., Zhu, Y., Liu, L., and X. Liu, "BGP Flow Specification
for SRv6", Work in Progress, Internet-Draft, draft-ietf-
idr-flowspec-srv6-00, 8 October 2021,
<https://www.ietf.org/archive/id/draft-ietf-idr-flowspec-
srv6-00.txt>.
[I-D.ietf-idr-wide-bgp-communities]
Raszuk, R., Haas, J., Lange, A., Decraene, B., Amante, S.,
and P. Jakma, "BGP Community Container Attribute", Work in
Progress, Internet-Draft, draft-ietf-idr-wide-bgp-
communities-05, 2 July 2018,
<https://www.ietf.org/archive/id/draft-ietf-idr-wide-bgp-
communities-05.txt>.
[RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>.
[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>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
Communities Attribute", RFC 4360, DOI 10.17487/RFC4360,
February 2006, <https://www.rfc-editor.org/info/rfc4360>.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760,
DOI 10.17487/RFC4760, January 2007,
<https://www.rfc-editor.org/info/rfc4760>.
[RFC5065] Traina, P., McPherson, D., and J. Scudder, "Autonomous
System Confederations for BGP", RFC 5065,
DOI 10.17487/RFC5065, August 2007,
<https://www.rfc-editor.org/info/rfc5065>.
[RFC6482] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
Origin Authorizations (ROAs)", RFC 6482,
DOI 10.17487/RFC6482, February 2012,
<https://www.rfc-editor.org/info/rfc6482>.
Hares, et al. Expires 27 April 2022 [Page 59]
Internet-Draft BGP FlowSpec v2 October 2021
[RFC7153] Rosen, E. and Y. Rekhter, "IANA Registries for BGP
Extended Communities", RFC 7153, DOI 10.17487/RFC7153,
March 2014, <https://www.rfc-editor.org/info/rfc7153>.
[RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K.
Patel, "Revised Error Handling for BGP UPDATE Messages",
RFC 7606, DOI 10.17487/RFC7606, August 2015,
<https://www.rfc-editor.org/info/rfc7606>.
[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>.
[RFC8955] Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M.
Bacher, "Dissemination of Flow Specification Rules",
RFC 8955, DOI 10.17487/RFC8955, December 2020,
<https://www.rfc-editor.org/info/rfc8955>.
[RFC8956] Loibl, C., Ed., Raszuk, R., Ed., and S. Hares, Ed.,
"Dissemination of Flow Specification Rules for IPv6",
RFC 8956, DOI 10.17487/RFC8956, December 2020,
<https://www.rfc-editor.org/info/rfc8956>.
[RFC9015] Farrel, A., Drake, J., Rosen, E., Uttaro, J., and L.
Jalil, "BGP Control Plane for the Network Service Header
in Service Function Chaining", RFC 9015,
DOI 10.17487/RFC9015, June 2021,
<https://www.rfc-editor.org/info/rfc9015>.
[RFC9117] Uttaro, J., Alcaide, J., Filsfils, C., Smith, D., and P.
Mohapatra, "Revised Validation Procedure for BGP Flow
Specifications", RFC 9117, DOI 10.17487/RFC9117, August
2021, <https://www.rfc-editor.org/info/rfc9117>.
12.2. Informative References
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8205] Lepinski, M., Ed. and K. Sriram, Ed., "BGPsec Protocol
Specification", RFC 8205, DOI 10.17487/RFC8205, September
2017, <https://www.rfc-editor.org/info/rfc8205>.
Hares, et al. Expires 27 April 2022 [Page 60]
Internet-Draft BGP FlowSpec v2 October 2021
[RFC8206] George, W. and S. Murphy, "BGPsec Considerations for
Autonomous System (AS) Migration", RFC 8206,
DOI 10.17487/RFC8206, September 2017,
<https://www.rfc-editor.org/info/rfc8206>.
Authors' Addresses
Susan Hares
Hickory Hill Consulting
7453 Hickory Hill
Saline, MI 48176
United States of America
Email: shares@ndzh.com
Donald Eastlake
Futurewei Technologies
2396 Panoramic Circle
Apopka, FL 32703
United States of America
Phone: +1-508-333-2270
Email: d3e3e3@gmail.com
Chaitanya Yadlapalli
ATT
United States of America
Email: cy098d@att.com
Sven Maduschke
Verizon
Germany
Email: sven.maduschke@de.verizon.com
Hares, et al. Expires 27 April 2022 [Page 61]