draft-ietf-idr-flow-spec-v6-22.txt   rfc8956.txt 
IDR Working Group C. Loibl, Ed. Internet Engineering Task Force (IETF) C. Loibl, Ed.
Internet-Draft next layer Telekom GmbH Request for Comments: 8956 next layer Telekom GmbH
Updates: I-D.ietf-idr-rfc5575bis (if R. Raszuk, Ed. Updates: 8955 R. Raszuk, Ed.
approved) Bloomberg LP Category: Standards Track NTT Network Innovations
Intended status: Standards Track S. Hares, Ed. ISSN: 2070-1721 S. Hares, Ed.
Expires: June 17, 2021 Huawei Huawei
December 14, 2020 December 2020
Dissemination of Flow Specification Rules for IPv6 Dissemination of Flow Specification Rules for IPv6
draft-ietf-idr-flow-spec-v6-22
Abstract Abstract
Dissemination of Flow Specification Rules I-D.ietf-idr-rfc5575bis "Dissemination of Flow Specification Rules" (RFC 8955) provides a
provides a Border Gateway Protocol extension for the propagation of Border Gateway Protocol (BGP) extension for the propagation of
traffic flow information for the purpose of rate limiting or traffic flow information for the purpose of rate limiting or
filtering IPv4 protocol data packets. filtering IPv4 protocol data packets.
This document extends I-D.ietf-idr-rfc5575bis with IPv6 This document extends RFC 8955 with IPv6 functionality. It also
functionality. It also updates I-D.ietf-idr-rfc5575bis by changing updates RFC 8955 by changing the IANA Flow Spec Component Types
the IANA Flow Spec Component Types registry. registry.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
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 This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on June 17, 2021. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8956.
Copyright Notice Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction
1.1. Definitions of Terms Used in This Memo . . . . . . . . . 3 1.1. Definitions of Terms Used in This Memo
2. IPv6 Flow Specification encoding in BGP . . . . . . . . . . . 3 2. IPv6 Flow Specification Encoding in BGP
3. IPv6 Flow Specification components . . . . . . . . . . . . . 3 3. IPv6 Flow Specification Components
3.1. Type 1 - Destination IPv6 Prefix . . . . . . . . . . . . 4 3.1. Type 1 - Destination IPv6 Prefix
3.2. Type 2 - Source IPv6 Prefix . . . . . . . . . . . . . . . 4 3.2. Type 2 - Source IPv6 Prefix
3.3. Type 3 - Upper-Layer Protocol . . . . . . . . . . . . . . 5 3.3. Type 3 - Upper-Layer Protocol
3.4. Type 7 - ICMPv6 Type . . . . . . . . . . . . . . . . . . 5 3.4. Type 7 - ICMPv6 Type
3.5. Type 8 - ICMPv6 Code . . . . . . . . . . . . . . . . . . 5 3.5. Type 8 - ICMPv6 Code
3.6. Type 12 - Fragment . . . . . . . . . . . . . . . . . . . 6 3.6. Type 12 - Fragment
3.7. Type 13 - Flow Label (new) . . . . . . . . . . . . . . . 7 3.7. Type 13 - Flow Label (new)
3.8. Encoding Example . . . . . . . . . . . . . . . . . . . . 7 3.8. Encoding Examples
4. Ordering of Flow Specifications . . . . . . . . . . . . . . . 9 4. Ordering of Flow Specifications
5. Validation Procedure . . . . . . . . . . . . . . . . . . . . 10 5. Validation Procedure
6. IPv6 Traffic Filtering Action changes . . . . . . . . . . . . 10 6. IPv6 Traffic Filtering Action Changes
6.1. Redirect IPv6 (rt-redirect-ipv6) Type TBD . . . . . . . . 10 6.1. Redirect IPv6 (rt-redirect-ipv6) Type 0x000d
7. Security Considerations . . . . . . . . . . . . . . . . . . . 10 7. Security Considerations
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 8. IANA Considerations
8.1. Flow Spec IPv6 Component Types . . . . . . . . . . . . . 11 8.1. Flow Spec IPv6 Component Types
8.1.1. Registry Template . . . . . . . . . . . . . . . . . . 11
8.1.2. Registry Contents . . . . . . . . . . . . . . . . . . 11
8.2. IPv6-Address-Specific Extended Community Flow Spec IPv6 8.2. IPv6-Address-Specific Extended Community Flow Spec IPv6
Actions . . . . . . . . . . . . . . . . . . . . . . . . . 13 Actions
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14 9. Normative References
10. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 14 Appendix A. Example Python Code: flow_rule_cmp_v6
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 14 Acknowledgments
11.1. Normative References . . . . . . . . . . . . . . . . . . 14 Contributors
11.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Authors' Addresses
Appendix A. Example python code: flow_rule_cmp_v6 . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction 1. Introduction
The growing amount of IPv6 traffic in private and public networks The growing amount of IPv6 traffic in private and public networks
requires the extension of tools used in IPv4-only networks to also requires the extension of tools used in IPv4-only networks to also
support IPv6 data packets. support IPv6 data packets.
This document analyzes the differences between describing IPv6 This document analyzes the differences between describing IPv6
[RFC8200] flows and those of IPv4 packets. It specifies new Border [RFC8200] flows and those of IPv4 packets. It specifies new Border
Gateway Protocol [RFC4271] encoding formats to enable Dissemination Gateway Protocol [RFC4271] encoding formats to enable "Dissemination
of Flow Specification Rules [I-D.ietf-idr-rfc5575bis] for IPv6. of Flow Specification Rules" [RFC8955] for IPv6.
This specification is an extension of the base This specification is an extension of the base established in
[I-D.ietf-idr-rfc5575bis]. It only defines the delta changes [RFC8955]. It only defines the delta changes required to support
required to support IPv6 while all other definitions and operation IPv6, while all other definitions and operation mechanisms of
mechanisms of Dissemination of Flow Specification Rules will remain "Dissemination of Flow Specification Rules" will remain in the main
in the main specification and will not be repeated here. specification and will not be repeated here.
1.1. Definitions of Terms Used in This Memo 1.1. Definitions of Terms Used in This Memo
AFI - Address Family Identifier. AFI: Address Family Identifier
AS - Autonomous System. AS: Autonomous System
NLRI - Network Layer Reachability Information. NLRI: Network Layer Reachability Information
SAFI - Subsequent Address Family Identifier. SAFI: Subsequent Address Family Identifier
VRF - Virtual Routing and Forwarding instance. VRF: Virtual Routing and Forwarding
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
2. IPv6 Flow Specification encoding in BGP 2. IPv6 Flow Specification Encoding in BGP
[I-D.ietf-idr-rfc5575bis] defines SAFIs 133 (Dissemination of Flow [RFC8955] defines SAFIs 133 (Dissemination of Flow Specification
Specification) and 134 (L3VPN Dissemination of Flow Specification) in rules) and 134 (L3VPN Dissemination of Flow Specification rules) in
order to carry the corresponding Flow Specification. order to carry the corresponding Flow Specification.
Implementations wishing to exchange IPv6 Flow Specifications MUST use Implementations wishing to exchange IPv6 Flow Specifications MUST use
BGP's Capability Advertisement facility to exchange the Multiprotocol BGP's Capability Advertisement facility to exchange the Multiprotocol
Extension Capability Code (Code 1) as defined in [RFC4760]. The Extension Capability Code (Code 1), as defined in [RFC4760]. The
(AFI, SAFI) pair carried in the Multiprotocol Extension Capability (AFI, SAFI) pair carried in the Multiprotocol Extension Capability
MUST be: (AFI=2, SAFI=133) for IPv6 Flow Specification, and (AFI=2, MUST be (AFI=2, SAFI=133) for IPv6 Flow Specification rules and
SAFI=134) for VPNv6 Flow Specification. (AFI=2, SAFI=134) for L3VPN Dissemination of Flow Specification
rules.
3. IPv6 Flow Specification components 3. IPv6 Flow Specification Components
The encoding of each of the components begins with a type field (1 The encoding of each of the components begins with a Type field (1
octet) followed by a variable length parameter. The following octet) followed by a variable length parameter. The following
sections define component types and parameter encodings for IPv6. sections define component types and parameter encodings for IPv6.
Types 4 (Port), 5 (Destination Port), 6 (Source Port), 9 (TCP flags), Types 4 (Port), 5 (Destination Port), 6 (Source Port), 9 (TCP Flags),
10 (Packet length) and 11 (DSCP), as defined in 10 (Packet Length), and 11 (DSCP), as defined in [RFC8955], also
apply to IPv6. Note that IANA has updated the "Flow Spec Component
[I-D.ietf-idr-rfc5575bis], also apply to IPv6. Note that IANA is Types" registry in order to contain both IPv4 and IPv6 Flow
requested to update the "Flow Spec Component Types" registry in order Specification component type numbers in a single registry
to contain both IPv4 and IPv6 Flow Specification component type (Section 8).
numbers in a single registry (Section 8).
3.1. Type 1 - Destination IPv6 Prefix 3.1. Type 1 - Destination IPv6 Prefix
Encoding: <type (1 octet), length (1 octet), offset (1 octet), Encoding: <type (1 octet), length (1 octet), offset (1 octet),
pattern (variable), padding(variable) > pattern (variable), padding (variable) >
Defines the destination prefix to match. The offset has been defined This defines the destination prefix to match. The offset has been
to allow for flexible matching to portions of an IPv6 address where defined to allow for flexible matching to portions of an IPv6 address
one is required to skip over the first N bits of the address (these where one is required to skip over the first N bits of the address.
bits skipped are often indicated as "don't care" bits). This can be (These bits skipped are often indicated as "don't care" bits.) This
especially useful where part of the IPv6 address consists of an can be especially useful where part of the IPv6 address consists of
embedded IPv4 address and matching needs to happen only on the an embedded IPv4 address, and matching needs to happen only on the
embedded IPv4 address. The encoded pattern contains enough octets embedded IPv4 address. The encoded pattern contains enough octets
for the bits used in matching (length minus offset bits). for the bits used in matching (length minus offset bits).
length - The length field indicates the N-th most significant bit in length: This indicates the N-th most significant bit in the
the address where bitwise pattern matching stops. address where bitwise pattern matching stops.
offset - The offset field indicates the number of most significant offset: This indicates the number of most significant address bits
address bits to skip before bitwise pattern matching starts. to skip before bitwise pattern matching starts.
pattern - Contains the matching pattern. The length of the pattern pattern: This contains the matching pattern. The length of the
is defined by the number of bits needed for pattern matching pattern is defined by the number of bits needed for
(length minus offset). pattern matching (length minus offset).
padding - The minimum number of bits required to pad the component padding: This contains the minimum number of bits required to pad
to an octet boundary. Padding bits MUST be 0 on encoding and MUST the component to an octet boundary. Padding bits MUST be
be ignored on decoding. 0 on encoding and MUST be ignored on decoding.
length = offset = 0 matches every address, otherwise length MUST be If length = 0 and offset = 0, this component matches every address;
in the range offset < length < 129 or the component is malformed. otherwise, length MUST be in the range offset < length < 129 or the
component is malformed.
Note: This Flow Specification component can be represented by the Note: This Flow Specification component can be represented by the
notation ipv6address/length if offset is 0, or ipv6address/offset- notation ipv6address/length if offset is 0 or ipv6address/offset-
length. The ipv6address in this notation is the textual IPv6 length. The ipv6address in this notation is the textual IPv6
representation of the pattern shifted to the right by the number of representation of the pattern shifted to the right by the number of
offset bits. See also Section 3.8. offset bits. See also Section 3.8.
3.2. Type 2 - Source IPv6 Prefix 3.2. Type 2 - Source IPv6 Prefix
Encoding: <type (1 octet), length (1 octet), offset (1 octet), Encoding: <type (1 octet), length (1 octet), offset (1 octet),
pattern (variable), padding(variable) > pattern (variable), padding (variable) >
Defines the source prefix to match. The length, offset, pattern and
padding are the same as in Section 3.1. This defines the source prefix to match. The length, offset,
pattern, and padding are the same as in Section 3.1.
3.3. Type 3 - Upper-Layer Protocol 3.3. Type 3 - Upper-Layer Protocol
Encoding: <type (1 octet), [numeric_op, value]+> Encoding: <type (1 octet), [numeric_op, value]+>
Contains a list of {numeric_op, value} pairs that are used to match This contains a list of {numeric_op, value} pairs that are used to
the first Next Header value octet in IPv6 packets that is not an match the first Next Header value octet in IPv6 packets that is not
extension header and thus indicates that the next item in the packet an extension header and thus indicates that the next item in the
is the corresponding upper-layer header (see [RFC8200] Section 4). packet is the corresponding upper-layer header (see Section 4 of
[RFC8200]).
This component uses the Numeric Operator (numeric_op) described in This component uses the Numeric Operator (numeric_op) described in
[I-D.ietf-idr-rfc5575bis] Section 4.2.1.1. Type 3 component values Section 4.2.1.1 of [RFC8955]. Type 3 component values SHOULD be
SHOULD be encoded as single octet (numeric_op len=00). encoded as a single octet (numeric_op len=00).
Note: While IPv6 allows for more than one Next Header field in the Note: While IPv6 allows for more than one Next Header field in the
packet, the main goal of the Type 3 Flow Specification component is packet, the main goal of the Type 3 Flow Specification component is
to match on the first upper-layer IP protocol value. Therefore the to match on the first upper-layer IP protocol value. Therefore, the
definition is limited to match only on this specific Next Header definition is limited to match only on this specific Next Header
field in the packet. field in the packet.
3.4. Type 7 - ICMPv6 Type 3.4. Type 7 - ICMPv6 Type
Encoding: <type (1 octet), [numeric_op, value]+> Encoding: <type (1 octet), [numeric_op, value]+>
Defines a list of {numeric_op, value} pairs used to match the type This defines a list of {numeric_op, value} pairs used to match the
field of an ICMPv6 packet (see also [RFC4443] Section 2.1). Type field of an ICMPv6 packet (see also Section 2.1 of [RFC4443]).
This component uses the Numeric Operator (numeric_op) described in This component uses the Numeric Operator (numeric_op) described in
[I-D.ietf-idr-rfc5575bis] Section 4.2.1.1. Type 7 component values Section 4.2.1.1 of [RFC8955]. Type 7 component values SHOULD be
SHOULD be encoded as single octet (numeric_op len=00). encoded as a single octet (numeric_op len=00).
In case of the presence of the ICMPv6 Type component only ICMPv6 In case of the presence of the ICMPv6 type component, only ICMPv6
packets can match the entire Flow Specification. The ICMPv6 Type packets can match the entire Flow Specification. The ICMPv6 type
component, if present, never matches when the packet's upper-layer IP component, if present, never matches when the packet's upper-layer IP
protocol value is not 58 (ICMPv6), if the packet is fragmented and protocol value is not 58 (ICMPv6), if the packet is fragmented and
this is not the first fragment, or if the system is unable to locate this is not the first fragment, or if the system is unable to locate
the transport header. Different implementations may or may not be the transport header. Different implementations may or may not be
able to decode the transport header. able to decode the transport header.
3.5. Type 8 - ICMPv6 Code 3.5. Type 8 - ICMPv6 Code
Encoding: <type (1 octet), [numeric_op, value]+> Encoding: <type (1 octet), [numeric_op, value]+>
Defines a list of {numeric_op, value} pairs used to match the code This defines a list of {numeric_op, value} pairs used to match the
field of an ICMPv6 packet (see also [RFC4443] Section 2.1). code field of an ICMPv6 packet (see also Section 2.1 of [RFC4443]).
This component uses the Numeric Operator (numeric_op) described in This component uses the Numeric Operator (numeric_op) described in
[I-D.ietf-idr-rfc5575bis] Section 4.2.1.1. Type 8 component values Section 4.2.1.1 of [RFC8955]. Type 8 component values SHOULD be
SHOULD be encoded as single octet (numeric_op len=00). encoded as a single octet (numeric_op len=00).
In case of the presence of the ICMPv6 Code component only ICMPv6 In case of the presence of the ICMPv6 code component, only ICMPv6
packets can match the entire Flow Specification. The ICMPv6 code packets can match the entire Flow Specification. The ICMPv6 code
component, if present, never matches when the packet's upper-layer IP component, if present, never matches when the packet's upper-layer IP
protocol value is not 58 (ICMPv6), if the packet is fragmented and protocol value is not 58 (ICMPv6), if the packet is fragmented and
this is not the first fragment, or if the system is unable to locate this is not the first fragment, or if the system is unable to locate
the transport header. Different implementations may or may not be the transport header. Different implementations may or may not be
able to decode the transport header. able to decode the transport header.
3.6. Type 12 - Fragment 3.6. Type 12 - Fragment
Encoding: <type (1 octet), [bitmask_op, bitmask]+> Encoding: <type (1 octet), [bitmask_op, bitmask]+>
Defines a list of {bitmask_op, bitmask} pairs used to match specific This defines a list of {bitmask_op, bitmask} pairs used to match
IP fragments. specific IP fragments.
This component uses the Bitmask Operator (bitmask_op) described in This component uses the Bitmask Operator (bitmask_op) described in
[I-D.ietf-idr-rfc5575bis] Section 4.2.1.2. The Type 12 component Section 4.2.1.2 of [RFC8955]. The Type 12 component bitmask MUST be
bitmask MUST be encoded as single octet bitmask (bitmask_op len=00). encoded as a single octet bitmask (bitmask_op len=00).
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+
| 0 | 0 | 0 | 0 |LF |FF |IsF| 0 | | 0 | 0 | 0 | 0 |LF |FF |IsF| 0 |
+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+
Figure 1: Fragment Bitmask Operand Figure 1: Fragment Bitmask Operand
Bitmask values: Bitmask values:
IsF - Is a fragment other than the first - match if IPv6 Fragment IsF: Is a fragment other than the first -- match if IPv6 Fragment
Header ([RFC8200] Section 4.5) Fragment Offset is not 0 Header (Section 4.5 of [RFC8200]) Fragment Offset is not 0
FF - First fragment - match if IPv6 Fragment Header ([RFC8200] FF: First fragment -- match if IPv6 Fragment Header (Section 4.5 of
Section 4.5) Fragment Offset is 0 AND M flag is 1 [RFC8200]) Fragment Offset is 0 AND M flag is 1
LF - Last fragment - match if IPv6 Fragment Header ([RFC8200] LF: Last fragment -- match if IPv6 Fragment Header (Section 4.5 of
Section 4.5) Fragment Offset is not 0 AND M flag is 0 [RFC8200]) Fragment Offset is not 0 AND M flag is 0
0 - MUST be set to 0 on NLRI encoding, and MUST be ignored during 0: MUST be set to 0 on NLRI encoding and MUST be ignored during
decoding decoding
3.7. Type 13 - Flow Label (new) 3.7. Type 13 - Flow Label (new)
Encoding: <type (1 octet), [numeric_op, value]+> Encoding: <type (1 octet), [numeric_op, value]+>
Contains a list of {numeric_op, value} pairs that are used to match This contains a list of {numeric_op, value} pairs that are used to
the 20-bit Flow Label IPv6 header field ([RFC8200] Section 3). match the 20-bit Flow Label IPv6 header field (Section 3 of
[RFC8200]).
This component uses the Numeric Operator (numeric_op) described in This component uses the Numeric Operator (numeric_op) described in
[I-D.ietf-idr-rfc5575bis] Section 4.2.1.1. Type 13 component values Section 4.2.1.1 of [RFC8955]. Type 13 component values SHOULD be
SHOULD be encoded as 4-octet quantities (numeric_op len=10). encoded as 4-octet quantities (numeric_op len=10).
3.8. Encoding Example 3.8. Encoding Examples
3.8.1. Example 1 3.8.1. Example 1
The following example demonstrates the prefix encoding for: "packets The following example demonstrates the prefix encoding for packets
from ::1234:5678:9a00:0/64-104 to 2001:db8::/32 and upper-layer- from ::1234:5678:9a00:0/64-104 to 2001:db8::/32 and upper-layer
protocol tcp". protocol tcp.
+--------+----------------------+-------------------------+----------+ +======+======================+=========================+==========+
| length | destination | source | ul-proto | | len | destination | source | ul-proto |
+--------+----------------------+-------------------------+----------+ +======+======================+=========================+==========+
| 0x12 | 01 20 00 20 01 0D B8 | 02 68 40 12 34 56 78 9A | 03 81 06 | | 0x12 | 01 20 00 20 01 0d bb | 02 68 40 12 34 56 78 9a | 03 81 06 |
+--------+----------------------+-------------------------+----------+ +------+----------------------+-------------------------+----------+
Table 1
Decoded: Decoded:
+-------+------------+-------------------------------+ +=======+============+=================================+
| Value | | | | Value | | |
+-------+------------+-------------------------------+ +=======+============+=================================+
| 0x12 | length | 18 octets (len<240 1-octet) | | 0x12 | length | 18 octets (if len<240, 1 octet) |
| 0x01 | type | Type 1 - Dest. IPv6 Prefix | +-------+------------+---------------------------------+
| 0x20 | length | 32 bit | | 0x01 | type | Type 1 - Dest. IPv6 Prefix |
| 0x00 | offset | 0 bit | +-------+------------+---------------------------------+
| 0x20 | pattern | | | 0x20 | length | 32 bits |
| 0x01 | pattern | | +-------+------------+---------------------------------+
| 0x0D | pattern | | | 0x00 | offset | 0 bits |
| 0xB8 | pattern | (no padding needed) | +-------+------------+---------------------------------+
| 0x02 | type | Type 2 - Source IPv6 Prefix | | 0x20 | pattern | |
| 0x68 | length | 104 bit | +-------+------------+---------------------------------+
| 0x40 | offset | 64 bit | | 0x01 | pattern | |
| 0x12 | pattern | | +-------+------------+---------------------------------+
| 0x34 | pattern | | | 0x0d | pattern | |
| 0x56 | pattern | | +-------+------------+---------------------------------+
| 0x78 | pattern | | | 0xb8 | pattern | (no padding needed) |
| 0x9A | pattern | (no padding needed) | +-------+------------+---------------------------------+
| 0x03 | type | Type 3 - upper-layer-proto | | 0x02 | type | Type 2 - Source IPv6 Prefix |
| 0x81 | numeric_op | end-of-list, value size=1, == | +-------+------------+---------------------------------+
| 0x06 | value | 06 | | 0x68 | length | 104 bits |
+-------+------------+-------------------------------+ +-------+------------+---------------------------------+
| 0x40 | offset | 64 bits |
+-------+------------+---------------------------------+
| 0x12 | pattern | |
+-------+------------+---------------------------------+
| 0x34 | pattern | |
+-------+------------+---------------------------------+
| 0x56 | pattern | |
+-------+------------+---------------------------------+
| 0x78 | pattern | |
+-------+------------+---------------------------------+
| 0x9a | pattern | (no padding needed) |
+-------+------------+---------------------------------+
| 0x03 | type | Type 3 - Upper-Layer Protocol |
+-------+------------+---------------------------------+
| 0x81 | numeric_op | end-of-list, value size=1, == |
+-------+------------+---------------------------------+
| 0x06 | value | 06 |
+-------+------------+---------------------------------+
This constitutes a NLRI with a NLRI length of 18 octets. Table 2
This constitutes an NLRI with an NLRI length of 18 octets.
Padding is not needed either for the destination prefix pattern Padding is not needed either for the destination prefix pattern
(length - offset = 32 bit) or for the source prefix pattern (length - (length - offset = 32 bits) or for the source prefix pattern (length
offset = 40 bit), as both patterns end on an octet boundary. - offset = 40 bits), as both patterns end on an octet boundary.
3.8.2. Example 2 3.8.2. Example 2
The following example demonstrates the prefix encoding for: "all The following example demonstrates the prefix encoding for all
packets from ::1234:5678:9a00:0/65-104 to 2001:db8::/32". packets from ::1234:5678:9a00:0/65-104 to 2001:db8::/32.
+--------+----------------------+-------------------------+ +========+======================+=========================+
| length | destination | source | | length | destination | source |
+--------+----------------------+-------------------------+ +========+======================+=========================+
| 0x0f | 01 20 00 20 01 0D B8 | 02 68 41 24 68 ac f1 34 | | 0x0f | 01 20 00 20 01 0d b8 | 02 68 41 24 68 ac f1 34 |
+--------+----------------------+-------------------------+ +--------+----------------------+-------------------------+
Table 3
Decoded: Decoded:
+-------+-------------+-------------------------------+ +=======+=============+=================================+
| Value | | | | Value | | |
+-------+-------------+-------------------------------+ +=======+=============+=================================+
| 0x0f | length | 15 octets (len<240 1-octet) | | 0x0f | length | 15 octets (if len<240, 1 octet) |
| 0x01 | type | Type 1 - Dest. IPv6 Prefix | +-------+-------------+---------------------------------+
| 0x20 | length | 32 bit | | 0x01 | type | Type 1 - Dest. IPv6 Prefix |
| 0x00 | offset | 0 bit | +-------+-------------+---------------------------------+
| 0x20 | pattern | | | 0x20 | length | 32 bits |
| 0x01 | pattern | | +-------+-------------+---------------------------------+
| 0x0D | pattern | | | 0x00 | offset | 0 bits |
| 0xB8 | pattern | (no padding needed) | +-------+-------------+---------------------------------+
| 0x02 | type | Type 2 - Source IPv6 Prefix | | 0x20 | pattern | |
| 0x68 | length | 104 bit | +-------+-------------+---------------------------------+
| 0x41 | offset | 65 bit | | 0x01 | pattern | |
| 0x24 | pattern | | +-------+-------------+---------------------------------+
| 0x68 | pattern | | | 0x0d | pattern | |
| 0xac | pattern | | +-------+-------------+---------------------------------+
| 0xf1 | pattern | | | 0xb8 | pattern | (no padding needed) |
| 0x34 | pattern/pad | (contains 1 bit padding) | +-------+-------------+---------------------------------+
+-------+-------------+-------------------------------+ | 0x02 | type | Type 2 - Source IPv6 Prefix |
+-------+-------------+---------------------------------+
| 0x68 | length | 104 bits |
+-------+-------------+---------------------------------+
| 0x41 | offset | 65 bits |
+-------+-------------+---------------------------------+
| 0x24 | pattern | |
+-------+-------------+---------------------------------+
| 0x68 | pattern | |
+-------+-------------+---------------------------------+
| 0xac | pattern | |
+-------+-------------+---------------------------------+
| 0xf1 | pattern | |
+-------+-------------+---------------------------------+
| 0x34 | pattern/pad | (contains 1 bit of padding) |
+-------+-------------+---------------------------------+
This constitutes a NLRI with a NLRI length of 15 octets. Table 4
This constitutes an NLRI with an NLRI length of 15 octets.
The source prefix pattern is 104 - 65 = 39 bits in length. After the The source prefix pattern is 104 - 65 = 39 bits in length. After the
pattern one bit of padding needs to be added so that the component pattern, one bit of padding needs to be added so that the component
ends on a octet boundary. However, only the first 39 bits are ends on an octet boundary. However, only the first 39 bits are
actually used for bitwise pattern matching starting with a 65 bit actually used for bitwise pattern matching, starting with a 65-bit
offset from the topmost bit of the address. offset from the topmost bit of the address.
4. Ordering of Flow Specifications 4. Ordering of Flow Specifications
The definition for the order of traffic filtering rules from The definition for the order of traffic filtering rules from
[I-D.ietf-idr-rfc5575bis] Section 5.1 is reused with new Section 5.1 of [RFC8955] is reused with new consideration for the
consideration for the IPv6 prefix offset. As long as the offsets are IPv6 prefix offset. As long as the offsets are equal, the comparison
equal, the comparison is the same, retaining longest-prefix-match is the same, retaining longest-prefix-match semantics. If the
semantics. If the offsets are not equal, the lowest offset has offsets are not equal, the lowest offset has precedence, as this Flow
precedence, as this Flow Specification matches the most significant Specification matches the most significant bit.
bit.
The code in Appendix A shows a Python3 implementation of the The code in Appendix A shows a Python3 implementation of the
resulting comparison algorithm. The full code was tested with Python resulting comparison algorithm. The full code was tested with Python
3.7.2 and can be obtained at https://github.com/stoffi92/draft-ietf- 3.7.2 and can be obtained at <https://github.com/stoffi92/draft-ietf-
idr-flow-spec-v6/tree/master/flowspec-cmp [1]. idr-flow-spec-v6/tree/master/flowspec-cmp>.
5. Validation Procedure 5. Validation Procedure
The validation procedure is the same as specified in The validation procedure is the same as specified in Section 6 of
[I-D.ietf-idr-rfc5575bis] Section 6 with the exception that item a) [RFC8955] with the exception that item a) of the validation procedure
of the validation procedure should now read as follows: should now read as follows:
a) A destination prefix component with offset=0 is embedded in the | a) A destination prefix component with offset=0 is embedded in
Flow Specification | the Flow Specification
6. IPv6 Traffic Filtering Action changes 6. IPv6 Traffic Filtering Action Changes
Traffic Filtering Actions from [I-D.ietf-idr-rfc5575bis] Section 7 Traffic Filtering Actions from Section 7 of [RFC8955] can also be
can also be applied to IPv6 Flow Specifications. To allow an IPv6- applied to IPv6 Flow Specifications. To allow an IPv6-Address-
Address-Specific Route-Target, a new Traffic Filtering Action IPv6- Specific Route-Target, a new Traffic Filtering Action IPv6-Address-
Address-Specific Extended Community [RFC5701] is specified in Specific Extended Community is specified in Section 6.1 below.
Section 6.1 below.
6.1. Redirect IPv6 (rt-redirect-ipv6) Type TBD 6.1. Redirect IPv6 (rt-redirect-ipv6) Type 0x000d
The redirect IPv6-Address-Specific Extended Community allows the The redirect IPv6-Address-Specific Extended Community allows the
traffic to be redirected to a VRF routing instance that lists the traffic to be redirected to a VRF routing instance that lists the
specified IPv6-Address-Specific Route-Target in its import policy. specified IPv6-Address-Specific Route-Target in its import policy.
If several local instances match this criteria, the choice between If several local instances match this criteria, the choice between
them is a local matter (for example, the instance with the lowest them is a local matter (for example, the instance with the lowest
Route Distinguisher value can be elected). Route Distinguisher value can be elected).
This IPv6-Address-Specific Extended Community uses the same encoding This IPv6-Address-Specific Extended Community uses the same encoding
as the IPv6-Address-Specific Route-Target Extended Community as the IPv6-Address-Specific Route-Target Extended Community
[RFC5701] Section 2 with the Type value always TBD. (Section 2 of [RFC5701]) with the Type value always 0x000d.
The Local Administrator sub-field contains a number from a numbering The Local Administrator subfield contains a number from a numbering
space that is administered by the organization to which the IP space that is administered by the organization to which the IP
address carried in the Global Administrator sub-field has been address carried in the Global Administrator subfield has been
assigned by an appropriate authority. assigned by an appropriate authority.
Interferes with: All BGP Flow Specification redirect Traffic Interferes with: All BGP Flow Specification redirect Traffic
Filtering Actions (with itself and those specified in Filtering Actions (with itself and those specified in Section 7.4 of
[I-D.ietf-idr-rfc5575bis] Section 7.4). [RFC8955]).
7. Security Considerations 7. Security Considerations
This document extends the functionality in [I-D.ietf-idr-rfc5575bis] This document extends the functionality in [RFC8955] to be applicable
to be applicable to IPv6 data packets. The same Security to IPv6 data packets. The same security considerations from
Considerations from [I-D.ietf-idr-rfc5575bis] now also apply to IPv6 [RFC8955] now also apply to IPv6 networks.
networks.
[RFC7112] describes the impact of oversized IPv6 header chains when [RFC7112] describes the impact of oversized IPv6 header chains when
trying to match on the transport header; [RFC8200] Section 4.5 also trying to match on the transport header; Section 4.5 of [RFC8200]
requires that the first fragment must include the upper-layer header also requires that the first fragment must include the upper-layer
but there could be wrongly formatted packets not respecting header, but there could be wrongly formatted packets not respecting
[RFC8200]. IPv6 Flow Specification component type 3 (Section 3.3) [RFC8200]. IPv6 Flow Specification component Type 3 (Section 3.3)
will not be enforced for those illegal packets. Moreover, there are will not be enforced for those illegal packets. Moreover, there are
hardware limitations in several routers ([RFC8883] Section 1) that hardware limitations in several routers (Section 1 of [RFC8883]) that
may make it impossible to enforce a policy signaled by a type 3 Flow may make it impossible to enforce a policy signaled by a Type 3 Flow
Specification component or Flow Specification components that match Specification component or Flow Specification components that match
on upper-layer properties of the packet. on upper-layer properties of the packet.
8. IANA Considerations 8. IANA Considerations
This section complies with [RFC7153]. This section complies with [RFC7153].
8.1. Flow Spec IPv6 Component Types 8.1. Flow Spec IPv6 Component Types
IANA has created and maintains a registry entitled "Flow Spec IANA has created and maintains a registry entitled "Flow Spec
Component Types". IANA is requested to add [this document] to the Component Types". IANA has added this document as a reference for
reference for this registry. Furthermore the registry should be that registry. Furthermore, the registry has been updated to also
rewritten to also contain the IPv6 Flow Specification Component Types contain the IPv6 Flow Specification Component Types as described
as described below. The registration procedure should remain below. The registration procedure remains unchanged.
unchanged.
8.1.1. Registry Template 8.1.1. Registry Template
Type Value: Type Value: contains the assigned Flow Specification component type
Contains the assigned Flow Specification component type value. value
IPv4 Name: IPv4 Name: contains the associated IPv4 Flow Specification
Contains the associated IPv4 Flow Specification component name component name as specified in [RFC8955]
as specified in [I-D.ietf-idr-rfc5575bis].
IPv6 Name: IPv6 Name: contains the associated IPv6 Flow Specification
Contains the associated IPv6 Flow Specification component name component name as specified in this document
as specified in this document.
Reference: Reference: contains references to the specifications
Contains referenced to the specifications.
8.1.2. Registry Contents 8.1.2. Registry Contents
+ Type Value: 0 Type Value: 0
+ IPv4 Name: Reserved IPv4 Name: Reserved
+ IPv6 Name: Reserved IPv6 Name: Reserved
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 1 Type Value: 1
+ IPv4 Name: Destination Prefix IPv4 Name: Destination Prefix
+ IPv6 Name: Destination IPv6 Prefix IPv6 Name: Destination IPv6 Prefix
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 2 Type Value: 2
+ IPv4 Name: Source Prefix IPv4 Name: Source Prefix
+ IPv6 Name: Source IPv6 Prefix IPv6 Name: Source IPv6 Prefix
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 3 Type Value: 3
+ IPv4 Name: IP Protocol IPv4 Name: IP Protocol
+ IPv6 Name: Upper-Layer Protocol IPv6 Name: Upper-Layer Protocol
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 4 Type Value: 4
+ IPv4 Name: Port IPv4 Name: Port
+ IPv6 Name: Port IPv6 Name: Port
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 5 Type Value: 5
+ IPv4 Name: Destination Port IPv4 Name: Destination Port
+ IPv6 Name: Destination Port IPv6 Name: Destination Port
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 6 Type Value: 6
+ IPv4 Name: Source Port IPv4 Name: Source Port
+ IPv6 Name: Source Port IPv6 Name: Source Port
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 7 Type Value: 7
+ IPv4 Name: ICMP Type IPv4 Name: ICMP Type
+ IPv6 Name: ICMPv6 Type IPv6 Name: ICMPv6 Type
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 8 Type Value: 8
+ IPv4 Name: ICMP Code IPv4 Name: ICMP Code
+ IPv6 Name: ICMPv6 Code IPv6 Name: ICMPv6 Code
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 9 Type Value: 9
+ IPv4 Name: TCP Flags IPv4 Name: TCP Flags
+ IPv6 Name: TCP Flags IPv6 Name: TCP Flags
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 10 Type Value: 10
+ IPv4 Name: Packet Length IPv4 Name: Packet Length
+ IPv6 Name: Packet Length IPv6 Name: Packet Length
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 11 Type Value: 11
+ IPv4 Name: DSCP IPv4 Name: DSCP
+ IPv6 Name: DSCP IPv6 Name: DSCP
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 12 Type Value: 12
+ IPv4 Name: Fragment IPv4 Name: Fragment
+ IPv6 Name: Fragment IPv6 Name: Fragment
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
+ Type Value: 13 Type Value: 13
+ IPv4 Name: Unassigned IPv4 Name: Unassigned
+ IPv6 Name: Flow Label IPv6 Name: Flow Label
+ Reference: [this document] Reference: RFC 8956
+ Type Value: 14-254 Type Value: 14-254
+ IPv4 Name: Unassigned IPv4 Name: Unassigned
+ IPv6 Name: Unassigned IPv6 Name: Unassigned
+ Reference:
+ Type Value: 255 Type Value: 255
+ IPv4 Name: Reserved IPv4 Name: Reserved
+ IPv6 Name: Reserved IPv6 Name: Reserved
+ Reference: [I-D.ietf-idr-rfc5575bis] [this document] Reference: [RFC8955], RFC 8956
8.2. IPv6-Address-Specific Extended Community Flow Spec IPv6 Actions 8.2. IPv6-Address-Specific Extended Community Flow Spec IPv6 Actions
IANA maintains a registry entitled "Transitive IPv6-Address-Specific IANA maintains a registry entitled "Transitive IPv6-Address-Specific
Extended Community Types". For the purpose of this work, IANA is Extended Community Types". For the purpose of this work, IANA has
requested to assign a new value: assigned a new value:
+------------+-----------------------------------+-----------------+
| Type Value | Name | Reference |
+------------+-----------------------------------+-----------------+
| TBD | Flow spec rt-redirect-ipv6 format | [this document] |
+------------+-----------------------------------+-----------------+
Table 1: Registry: Transitive IPv6-Address-Specific Extended
Community Types
9. Acknowledgements
Authors would like to thank Pedro Marques, Hannes Gredler, Bruno
Rijsman, Brian Carpenter, and Thomas Mangin for their valuable input.
10. Contributors
Danny McPherson
Verisign, Inc.
Email: dmcpherson@verisign.com
Burjiz Pithawala
Individual
Email: burjizp@gmail.com
Andy Karch
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134
USA
Email: akarch@cisco.com
11. References +============+===================================+===========+
| Type Value | Name | Reference |
+============+===================================+===========+
| 0x000d | Flow spec rt-redirect-ipv6 format | RFC 8956 |
+------------+-----------------------------------+-----------+
11.1. Normative References Table 5: Transitive IPv6-Address-Specific Extended
Community Types Registry
[I-D.ietf-idr-rfc5575bis] 9. Normative References
Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M.
Bacher, "Dissemination of Flow Specification Rules",
draft-ietf-idr-rfc5575bis-27 (work in progress), October
2020.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271, Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006, DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>. <https://www.rfc-editor.org/info/rfc4271>.
skipping to change at page 16, line 5 skipping to change at line 659
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6 [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200, (IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017, DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>. <https://www.rfc-editor.org/info/rfc8200>.
[RFC8883] Herbert, T., "ICMPv6 Errors for Discarding Packets Due to [RFC8883] Herbert, T., "ICMPv6 Errors for Discarding Packets Due to
Processing Limits", RFC 8883, DOI 10.17487/RFC8883, Processing Limits", RFC 8883, DOI 10.17487/RFC8883,
September 2020, <https://www.rfc-editor.org/info/rfc8883>. September 2020, <https://www.rfc-editor.org/info/rfc8883>.
11.2. URIs [RFC8955] Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M.
Bacher, "Dissemination of Flow Specification Rules",
[1] https://github.com/stoffi92/draft-ietf-idr-flow-spec- RFC 8955, DOI 10.17487/RFC8955, December 2020,
v6/tree/master/flowspec-cmp <https://www.rfc-editor.org/info/rfc8955>.
Appendix A. Example python code: flow_rule_cmp_v6 Appendix A. Example Python Code: flow_rule_cmp_v6
<CODE BEGINS> <CODE BEGINS>
""" """
Copyright (c) 2020 IETF Trust and the persons identified as authors Copyright (c) 2020 IETF Trust and the persons identified as authors
of the code. All rights reserved. of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without Redistribution and use in source and binary forms, with or without
modification, is permitted pursuant to, and subject to the license modification, is permitted pursuant to, and subject to the license
terms contained in, the Simplified BSD License set forth in Section terms contained in, the Simplified BSD License set forth in Section
4.c of the IETF Trust's Legal Provisions Relating to IETF Documents 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents
skipping to change at page 17, line 43 skipping to change at line 744
# use the below algorithm for sorting # use the below algorithm for sorting
result = flow_rule_cmp_v6(self, other) result = flow_rule_cmp_v6(self, other)
if result == B_HAS_PRECEDENCE: if result == B_HAS_PRECEDENCE:
return True return True
else: else:
return False return False
def flow_rule_cmp_v6(a, b): def flow_rule_cmp_v6(a, b):
""" """
Implementation of the flowspec sorting algorithm in Implementation of the flowspec sorting algorithm in
draft-ietf-idr-flow-spec-v6. RFC 8956.
""" """
for comp_a, comp_b in itertools.zip_longest(a.components, for comp_a, comp_b in itertools.zip_longest(a.components,
b.components): b.components):
# If a component type does not exist in one rule # If a component type does not exist in one rule
# this rule has lower precedence # this rule has lower precedence
if not comp_a: if not comp_a:
return B_HAS_PRECEDENCE return B_HAS_PRECEDENCE
if not comp_b: if not comp_b:
return A_HAS_PRECEDENCE return A_HAS_PRECEDENCE
# Higher precedence for lower component type # Higher precedence for lower component type
if comp_a.component_type < comp_b.component_type: if comp_a.component_type < comp_b.component_type:
return A_HAS_PRECEDENCE return A_HAS_PRECEDENCE
if comp_a.component_type > comp_b.component_type: if comp_a.component_type > comp_b.component_type:
return B_HAS_PRECEDENCE return B_HAS_PRECEDENCE
# component types are equal -> type specific comparison # component types are equal -> type-specific comparison
if comp_a.component_type in (IP_DESTINATION, IP_SOURCE): if comp_a.component_type in (IP_DESTINATION, IP_SOURCE):
if comp_a.offset < comp_b.offset: if comp_a.offset < comp_b.offset:
return A_HAS_PRECEDENCE return A_HAS_PRECEDENCE
if comp_a.offset > comp_b.offset: if comp_a.offset > comp_b.offset:
return B_HAS_PRECEDENCE return B_HAS_PRECEDENCE
# both components have the same offset # both components have the same offset
# assuming comp_a.value, comp_b.value of type # assuming comp_a.value, comp_b.value of type
# ipaddress.IPv6Network # ipaddress.IPv6Network
# and the offset bits are reset to 0 (since they are # and the offset bits are reset to 0 (since they are
# not represented in the NLRI) # not represented in the NLRI)
skipping to change at page 19, line 14 skipping to change at line 811
comp_b.value[:common]: comp_b.value[:common]:
return A_HAS_PRECEDENCE return A_HAS_PRECEDENCE
# the first common bytes match # the first common bytes match
elif len(comp_a.value) > len(comp_b.value): elif len(comp_a.value) > len(comp_b.value):
return A_HAS_PRECEDENCE return A_HAS_PRECEDENCE
else: else:
return B_HAS_PRECEDENCE return B_HAS_PRECEDENCE
return EQUAL return EQUAL
<CODE ENDS> <CODE ENDS>
Acknowledgments
The authors would like to thank Pedro Marques, Hannes Gredler, Bruno
Rijsman, Brian Carpenter, and Thomas Mangin for their valuable input.
Contributors
Danny McPherson
Verisign, Inc.
Email: dmcpherson@verisign.com
Burjiz Pithawala
Individual
Email: burjizp@gmail.com
Andy Karch
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134
United States of America
Email: akarch@cisco.com
Authors' Addresses Authors' Addresses
Christoph Loibl (editor) Christoph Loibl (editor)
next layer Telekom GmbH next layer Telekom GmbH
Mariahilfer Guertel 37/7 Mariahilfer Guertel 37/7
Vienna 1150 1150 Vienna
AT Austria
Phone: +43 664 1176414 Phone: +43 664 1176414
Email: cl@tix.at Email: cl@tix.at
Robert Raszuk (editor) Robert Raszuk (editor)
Bloomberg LP NTT Network Innovations
731 Lexington Ave 940 Stewart Dr
New York City, NY 10022 Sunnyvale, CA 94085
USA United States of America
Email: robert@raszuk.net Email: robert@raszuk.net
Susan Hares (editor) Susan Hares (editor)
Huawei Huawei
7453 Hickory Hill 7453 Hickory Hill
Saline, MI 48176 Saline, MI 48176
USA United States of America
Email: shares@ndzh.com Email: shares@ndzh.com
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