| Network Working Group | Z. Li |
| Internet-Draft | Huawei |
| Intended status: Standards Track | L. Ou |
| Expires: December 19, 2016 | Y. Luo |
| China Telcom Co., Ltd. | |
| S. Lu | |
| Tencent | |
| S. Zhuang | |
| N. Wu | |
| Huawei | |
| June 17, 2016 |
BGP FlowSpec Extensions for Routing Policy Distribution (RPD)
draft-li-idr-flowspec-rpd-02
This document describes a mechanism to use BGP Flowspec address family as routing-policy distribution protocol. This mechanism is called BGP FlowSpec Extensions for Routing Policy Distribution (BGP-FS RPD).
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 RFC 2119 [RFC2119].
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 http://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."
This Internet-Draft will expire on December 19, 2016.
Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.
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Some difficulties exist when optimize traffic paths on a traditional IP network:
Hence, an automatic mechanism for setting up routing policies is desirable which can simplify the complexity of routing policies configuration. This document describes a mechanism to use BGP Flowspec address family [RFC5575] as route-policy distribution protocol. This mechanism is called BGP FlowSpec Extensions for Routing Policy Distribution (BGP-FS RPD).
BGP Flow Specification route: BGP Flow Specification routes are defined in RFC 5575. Each BGP Flow Specification route contains BGP Network Layer Reachability Information (NLRI) and Extended Community Attributes, which carry traffic filtering rules and actions to be taken on filtered traffic.
BGP Flow Specification peer relationship: A BGP Flow Specification peer relationship is established between the device that generates BGP Flow Specification routes and each network ingress that will transmit the BGP Flow Specification routes. After receiving the BGP Flow Specification routes, the peer delivers preferred BGP Flow Specification routes to the forwarding plane. The routes are then converted into traffic policies that control attack traffic.
It is obvious that providers have the requirements to adjust their business traffic from time to time because:
Traffic from PE1 to Prefix1
----------------------------------->
+-----------------+ +-------------------------+
| +---------+ | L1 | +----+ +----------+|
| |Speaker1 | +------------+ |IGW1| |policy ||
| +---------+ |** L2**| +----+ |controller||
| | ** ** | +----------+|
| +---+ | **** | |
| |PE1| | **** | |
| +---+ | ** ** | |
| +---------+ |** L3**| +----+ |
| |Speaker2 | +------------+ |IGW2| AS100 |
| +---------+ | L4 | +----+ |
| | | |
| AS200 | | |
| | | ... |
| | | |
| +---------+ | | +----+ +-------+ |
| |Speakern | | | |IGWn| |Prefix1| |
| +---------+ | | +----+ +-------+ |
+-----------------+ +-------------------------+
Prefix1 advertise from AS100 to AS200
<----------------------------------------
Figure 1: Inbound Traffic Control case
In the scenario below, for reasons above, the provider of AS100 saying P may wish the inbound traffic from AS200 enters AS100 through link L3 instead of others. Since P doesn't have administration over AS200, so there is no way for P to modify the route selection criteria directly.
Traffic from PE2 to Prefix2
----------------------------------->
+-------------------------+ +-----------------+
|+----------+ +----+ |L1 | +---------+ |
||policy | |IGW1| +------------+ |Speaker1 | |
||controller| +----+ |** **| +---------+ |
|+----------+ |L2** ** | +-------+|
| | **** | |Prefix2||
| | **** | +-------+|
| |L3** ** | |
| AS100 +----+ |** **| +---------+ |
| |IGW2| +------------+ |Speaker2 | |
| +----+ |L4 | +---------+ |
| | | |
|+---+ | | AS200 |
||PE2| ... | | |
|+---+ | | |
| +----+ | | +---------+ |
| |IGWn| | | |Speakern | |
| +----+ | | +---------+ |
+-------------------------+ +-----------------+
Prefix2 advertise from AS200 to AS100
<----------------------------------------
Figure 2: Outbound Traffic Control case
In this scenario, the provider of AS100 saying P wishes to prefer link L3 for the traffic to the destination Prefix2 among multiple exits and links. This preference can be dynamic and change frequently because of the reasons above. So the provider P expects an efficient and convenient solution.
BGP FlowSpec [RFC5575] leverages the BGP control plane to simplify the distribution of filter rules. New filter rules can be injected to all BGP peers simultaneously without changing router configuration. Though the typical application of it is for DDOS mitigation, it doesn’t mean BGP Flowspec only takes effect on the forwarding plane.
This document introduces a mechanism that uses BGP Flowspec as a route-policy distribution protocol. It can be the same powerful as the device-based route-policy while still has the efficiency and convenience of BGP Flowspec.
This draft will use the term BGP-FS RPD as the abbreviation of FlowSpec Extensions for Routing Policy Distribution.
The traffic-action extended community consists of 6 bytes of which only the 2 least significant bits of the 6th byte (from left to right) are currently defined in [RFC5575]. Terminal Action (bit 47) and Sample (bit 46) defines in [RFC5575], this document defines Route Policy Distribution Flag(Bit 45).
The Flow Specification Traffic Actions for Routing Policy Distribution:
40 41 42 43 44 45 46 47 +---+---+---+---+---+---+---+---+ | reserved | R | S | T | +---+---+---+---+---+---+---+---+ Figure 3: FlowSpec Traffic-action
This document defines and uses a new BGP attribute called the "BGP Policy attribute". This is an optional BGP attribute. The format of this attribute is defined as follows:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Match fields (Variable) | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Action fields (Variable) | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4: BGP Policy Attribute
Action fields: Action fields define the action being applied to the target route.
Match Fields define the matching criteria for the BGP Policy Attribute.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Match Type (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Number of Sub-TLVs (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Sub-TLVs (Variable) | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5: Match Fields Format
Match Type:
0: Permit, specifies the permit mode of a match rule. If a route matches the matching criteria of the BGP Policy Attribute, the actions defined by the Action fields of the BGP Policy Attribute are performed. If a route does not match the matching criteria for the BGP Policy Attribute, then nothing needs to do with this route.
1: Deny, specifies the deny mode of a match rule. In the deny mode, If a route does not match the matching criteria of the BGP Policy Attribute, the actions defined by the Action fields of the BGP Policy Attribute are performed. If a route matches the matching criteria of the BGP Policy Attribute, then nothing needs to do with this route.
Number of Sub-TLVs: The number of Sub-TLVs contain in Match fields.
The contents of Match fields are encoded as Sub-TLVs, where each TLV has the following format:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Values (Variable) | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 6: Sub-TLVs Format
Type: The Type field contains a value of 1-65534. The values 0 and 65535 are reserved for future use.
Length: The Length field represents the total length of a given TLV's value field in octets.
Values: The Value field contains the TLV value.
Supported format of the TLVs can be:
Type 1: IPv4 Neighbor
Type 2: IPv6 Neighbor
Type 3: ASN List
...
To be added in later versions.
Action fields define the action being applied to the targeted route.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Action Type (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Action Length (2 octets) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Action Values (Variable) | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 7: Action Fields Format
Action Length: The Action Length field represents the total length of the Action Values in octets.
Action Values: The Action Values field contain parameters of the action.
Supported format of the TLVs can be:
Type 1: Route-Preference
Type 2: Route-Prepend-AS
...
To be added in later versions.
The traffic destined for Prefix1 needs to be scheduled to link Speaker1 -> IGW2 for transmission.
The Policy Controller constructs a BGP-FS RPD route and pushes it to all the IGW routers, the route carries:
IGW1 processes the received BGP-FS RPD route as follows:
IGW1 checks the matching criteria and finds that it doesn't hits the matching criteria: Local BGP Speaker IGW2, Remote BGP Speaker1, at the same time the Match Type is "Deny" mode, so IGW1 sends the best route of Prefix1 to Speaker1 and Speaker2 with performing the Action instructions from the BGP-FS RPD route: Prepend Local AS 5 times.
IGW2 processes the received BGP FS RPD route as follows:
IGW2 checks the matching criteria and finds that there is a speaker which hits the matching criteria: Local BGP Speaker IGW2, Remote BGP Peer Speaker1, but the Match Type is "Deny" mode, so IGW2 sends the best route of Prefix1 to Speaker1, without performing the Action instructions from the BGP-FS RPD route. At the same time, IGW2 sends the best route of Prefix1 to Speaker2 with performing the Action instructions from the BGP-FS RPD route: Prepend Local AS 5 times.
In the similar manner, other IGWs will perform the same Action instructions as IGW1. Then the traffic destined for Prefix1 has been be scheduled to link L3 for transmission.
In this scenario, if the bandwidth usage of a link exceeds the specified threshold, the Policy Controller automatically identifies which traffic needs to be scheduled and the Policy Controller automatically calculates traffic control paths based on network topology and traffic information.
For example, the outbound traffic destined for Prefix2 needs to be scheduled to link IGW2 -> Speaker1 for transmission.
Prefix Next-Hop Local BGP Speaker Remote BGP Peer
Prefix2 Speaker1 IGW2 Speaker1
Prefix2 Speaker2 IGW2 Speaker2
...
The Policy Controller sends a BGP-FS RPD route to IGW2, the route carries:
IGW2 processes the received BGP FS RPD route as follows:
So IGW2 chooses the BGP route received from Speaker1 instead of Speaker2 as the best route and the outbound traffic destined for Prefix2 can be scheduled to link L3 for transmission.
This section describes the option 2 for protocol extensions, which is completely different from section 5.2 by reusing BGP Wide Community introduced in [I-D.ietf-idr-wide-bgp-communities].
BGP Wide Community Attribute is a very useful tool that it can be used to convey different kinds of routing policies.
Wide Community Atoms define in [I-D.ietf-idr-wide-bgp-communities] , in that draft it defines Type 1 to Type 8.
New wide community atoms have to be introduced since the entrance and exit of traffic need to be designated precisely.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+
| Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Value (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: Wide Community Atoms
Supported format of the TLVs can be:
As required in the case, traffic from PE1 to Prefix1 need to enter through L3, so IGWs except IGW2 should prepend ASN list to Prefix1 when populating to AS100. As shown in figure below, community "PREPEND N TIMES BY AS" and "Exclude Target(s) TLV" are be used.
The encoding example using BGP Wide Community:
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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Container Type 1 (1) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1 0 0 0 0 0 0 0| +-+-+-+-+-+-+-+-+ | Hop Count: 0 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length: 36 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Community: PREPEND N TIMES BY AS 17 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Own ASN 100 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Context ASN# 100 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |ExcTargetTLV(2)| Length: 11 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4Neig(TBD)| Length: 8 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local Speaker #IGW2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote Speaker #Speaker1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Param TLV (3) | Length: 7 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Integer (4) | Length: 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Prepend # 5 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 9: Example encoding for Inbound Traffic Control case
[I-D.ietf-idr-registered-wide-bgp-communities].
The traffic destined for Prefix1 needs to be scheduled to link Speaker1 -> IGW2 for transmission.
The Policy Controller constructs a BGP-FS RPD route and pushes it to all the IGW routers, the route carries:
PREPEND N TIMES BY AS:
Type: 0x0001 S = src AS #
F = 0x80 C = 0x00000000
H = 0 T = none
L = 36 octets E = Type_TBD (BGP IPv4 neighbor)
R = 17 P = Type_4 (0x05)
Where "BGP IPv4 neighbor" Atom TLV contains:
The BGP session IPv4 local address: Local BGP Speaker IGW2
The BGP session IPv4 peer address: Remote BGP Peer Speaker1
IGW1 processes the received BGP-FS RPD route as follows:
IGW1 checks the matching criteria and finds that it doesn't hits the exclude matching criteria: Local BGP Speaker IGW2, Remote BGP Speaker1, so IGW1 sends the best route of Prefix1 to Speaker1 and Speaker2 with performing the Action instructions from the BGP-FS RPD route: Prepend Local AS 5 times.
IGW2 processes the received BGP FS RPD route as follows:
IGW2 checks the matching criteria and finds that there is a speaker which hits the exclude matching criteria: Local BGP Speaker IGW2, Remote BGP Peer Speaker1, so IGW2 sends the best route of Prefix1 to Speaker1 without performing the Action instructions from the BGP-FS RPD route, at the same time, IGW2 sends the best route of Prefix1 to Speaker2 with performing the Action instructions from the BGP-FS RPD route: Prepend Local AS 5 times.
In the similar manner, other IGWs will perform the same Action instructions as IGW1. Then the traffic destined for Prefix1 has been be scheduled to link L3 for transmission.
As required in the case, traffic from PE2 to Prefix2 need to exit through L3, so IGWs should perfer the route from IGW2 to Speaker1. As shown in figure below, community "LOCAL PREFERENCE" and "Target(s) TLV" are be used.
The encoding example using BGP Wide Community:
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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Container Type 1 (1) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1 0 0 0 0 0 0 0| +-+-+-+-+-+-+-+-+ | Hop Count: 0 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length: 36 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Community: LOCAL PREFERENCE 20 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Own ASN 100 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Context ASN# 100 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TargetTLV(1) | Length: 11 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4Neig(TBD)| Length: 8 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local Speaker #IGW2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote Speaker #Speaker1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Param TLV (3) | Length: 7 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Integer (4) | Length: 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Increment # 100 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 10: Example encoding for Outbound Traffic Control case
[I-D.ietf-idr-registered-wide-bgp-communities]
In this scenario, if the bandwidth usage of a link exceeds the specified threshold, the Policy Controller automatically identifies which traffic needs to be scheduled and the Policy Controller automatically calculates traffic control paths based on network topology and traffic information.
For example, the outbound traffic destined for Prefix2 needs to be scheduled to link IGW2 -> Speaker1 for transmission.
The Policy Controller sends a BGP-FS RPD route to IGW2, the route carries:
LOCAL PREFERENCE:
Type: 0x0001 S = src AS #
F = 0x80 C = 0x00000000
H = 0 T = Type_TBD (BGP IPv4 neighbor)
L = 36 octets E = none
R = 20 P = Type_4 (0x64)
Where "BGP IPv4 neighbor" Atom TLV contains:
The BGP session IPv4 local address: Local BGP Speaker IGW2
The BGP session IPv4 peer address: Remote BGP Peer Speaker1
IGW2 processes the received BGP FS RPD route as follows:
Prefix Next-Hop Local BGP Speaker Remote BGP Peer
--------------------------------------------------------
Prefix2 Speaker1 IGW2 Speaker1
Prefix2 Speaker2 IGW2 Speaker2
...
So IGW2 chooses the BGP route received from Speaker1 instead of Speaker2 as the best route and the outbound traffic destined for Prefix2 can be scheduled to link L3 for transmission.
It is necessary to negotiate the capability to support BGP FlowSpec Extensions for Route Policy Distribution (RPD). The BGP FS RPD Capability is a new BGP capability [RFC5492]. The Capability Code for this capability is to be specified by the IANA. The Capability Length field of this capability is variable. The Capability Value field consists of one or more of the following tuples:
+--------------------------------------------------+ | Address Family Identifier (2 octets) | +--------------------------------------------------+ | Subsequent Address Family Identifier (1 octet) | +--------------------------------------------------+ | Send/Receive (1 octet) | +--------------------------------------------------+ Figure 11: BGP FS RPD Capability
The meaning and use of the fields are as follows:
Address Family Identifier (AFI): This field is the same as the one used in [RFC4760].
Subsequent Address Family Identifier (SAFI): This field is the same as the one used in [RFC4760].
Send/Receive: This field indicates whether the sender is (a) willing to receive Route Policies via BGP FLowSpec from its peer (value 1), (b) would like to send Route Policies via BGP FLowSpec to its peer (value 2), or (c) both (value 3) for the <AFI, SAFI>.
Routing policies are used to filter routes and control how routes are received and advertised. If route attributes, such as reachability, are changed, the path along which network traffic passes changes accordingly.
When advertising, receiving, and importing routes, the router implements certain policies based on actual networking requirements to filter routes and change the attributes of the routes. Routing policies serve the following purposes:
Routing policies are implemented using the following procedures:
Peng Zhou Huawei Email: Jewpon.zhou@huawei.com
The following people have substantially contributed to the definition of the BGP-FS RPD and to the editing of this document:
TBD.
TBD.
The authors would like to thank Acee Lindem, Jeff Haas, Jie Dong, Haibo Wang, Lucy Yong, Qiandeng Liang, Zhenqiang Li for their comments to this work.
| [I-D.ietf-idr-wide-bgp-communities] | Raszuk, R., Haas, J., Lange, A., Amante, S., Decraene, B., Jakma, P. and R. Steenbergen, "Wide BGP Communities Attribute", Internet-Draft draft-ietf-idr-wide-bgp-communities-02, May 2016. |
| [RFC1997] | Chandra, R., Traina, P. and T. Li, "BGP Communities Attribute", RFC 1997, DOI 10.17487/RFC1997, August 1996. |
| [RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
| [RFC4271] | Rekhter, Y., Li, T. and S. Hares, "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, DOI 10.17487/RFC4271, January 2006. |
| [RFC4760] | Bates, T., Chandra, R., Katz, D. and Y. Rekhter, "Multiprotocol Extensions for BGP-4", RFC 4760, DOI 10.17487/RFC4760, January 2007. |
| [RFC5492] | Scudder, J. and R. Chandra, "Capabilities Advertisement with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February 2009. |
| [RFC5575] | Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J. and D. McPherson, "Dissemination of Flow Specification Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009. |
| [I-D.ietf-idr-registered-wide-bgp-communities] | Raszuk, R. and J. Haas, "Registered Wide BGP Community Values", Internet-Draft draft-ietf-idr-registered-wide-bgp-communities-02, May 2016. |