IDR Working Group R. Raszuk
Internet-Draft B. Pithawala
Intended status: Standards Track Cisco Systems
Expires: December 4, 2011 D. McPherson
Verisign, Inc.
June 2, 2011
Dissemination of Flow Specification Rules for IPv6
draft-ietf-idr-flow-spec-v6-00
Abstract
Dissemination of Flow Specification Rules [RFC5575] provides a
protocol extension for propagation of traffic flow information for
the purpose of rate limiting or filtering. The [RFC5575] specifies
those extensions for IPv4 protocol data packets.
This specification extends the current [RFC5575] and defines changes
to the original document in order to make it also usable and
applicable to IPv6 data packets.
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 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 4, 2011.
Copyright Notice
Copyright (c) 2011 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
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
Raszuk, et al. Expires December 4, 2011 [Page 1]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
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
2. IPv6 Flow Specification encoding in BGP . . . . . . . . . . . . 3
3. IPv6 Flow Specification types changes . . . . . . . . . . . . . 4
4. IPv6 Flow Specification Traffic Filtering Action changes . . . 5
5. Security considerations . . . . . . . . . . . . . . . . . . . . 6
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 6
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8.1. Normative References . . . . . . . . . . . . . . . . . . . 7
8.2. Informative References . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7
Raszuk, et al. Expires December 4, 2011 [Page 2]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
1. Introduction
The growing amount of IPv6 traffic in private and public networks
requires the extension of tools used in the IPv4 only networks to be
also capable of supporting IPv6 data packets.
In this document authors analyze the differences of IPv6 [RFC2460]
flows description from those of traditional IPv4 packets and propose
subset of new encoding formats to enable Dissemination of Flow
Specification Rules [RFC5575] for IPv6.
This specification should be treated as an extension of base
[RFC5575] specification and not its replacement. It only defines the
delta changes required to support IPv6 while all other definitions
and operation mechanisms of Dissemination of Flow Specification Rules
will remain in the main specification and will not be repeated here.
2. IPv6 Flow Specification encoding in BGP
The [RFC5575] defines a new SAFIs (133 for IPv4) and (134 for VPNv4)
applications in order to carry corresponding to each such application
flow specification.
This document will redefine the [RFC5575] SAFIs in order to make them
AFI specific and applicable to both IPv4 and IPv6 applications.
The following changes are defined:
"SAFI 133 for IPv4 dissemination of flow specification rules" to
now be defined as "SAFI 133 for IP dissemination of flow
specification rules"
"SAFI 134 for VPNv4 dissemination of flow specification rules" to
now be defined as "SAFI 134 for L3VPN dissemination of flow
specification rules"
For both SAFIs the indication to which address family they are
referring to will be recognized by AFI value (AFI=1 for IPv4 or
VPNv4, AFI=2 for IPv6 and VPNv6 respectively). Such modification is
fully backwards compatible with existing implementation and
production deployments.
It needs to be observed that such choice of proposed encoding is
compatible with filter validation against routing reachability
information as described in section 6 of RFC5575. Validation tables
will now be performed according to the following rules.
Raszuk, et al. Expires December 4, 2011 [Page 3]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
Flow specification received over AFI/SAFI=1/133 will be validated
against routing reachability received over AFI/SAFI=1/1
Flow specification received over AFI/SAFI=1/134 will be validated
against routing reachability received over AFI/SAFI=1/128
Flow specification received over AFI/SAFI=2/133 will be validated
against routing reachability received over AFI/SAFI=2/1
Flow specification received over AFI/SAFI=2/134 will be validated
against routing reachability received over AFI/SAFI=2/128
3. IPv6 Flow Specification types changes
The following component types are redefined or added for the purpose
of accommodating new IPv6 header encoding. Unless otherwise stated
all other types as defined in RFC5575 apply to IPv6 packets as is.
Type 1 - Destination IPv6 Prefix
Encoding: <type (1 octet), prefix length (1 octet), prefix offset
(1 octet), prefix>
Defines the destination prefix to match. Prefix offset has been
defined to allow for flexible match on the part of the IPv6
address where we want to skip (don't care) of N first bits of the
address. This can be especially useful where part of the IPv6
address consists of embedded IPv4 address and match needs to
happen only on the part of embedded IPv4 address. The default
value for prefix offset is 0x00 (match on all bits as indicated by
prefix length). Otherwise prefixes are encoded as in BGP UPDATE
messages, a length in bits is followed by enough octets to contain
the prefix information.
Type 2 - Source IPv6 Prefix
Encoding: <type (1 octet), prefix length (1 octet), prefix offset
(1 octet), prefix>
Defines the source prefix to match. Prefix offset has been
defined to allow for flexible match on the part of the IPv6
address where we want to skip (don't care) of N first bits of the
address. This can be especially useful where part of the IPv6
address consists of embedded IPv4 address and match needs to
happen only on the part of embedded IPv4 address. The default
value for prefix offset is 0x00 (match on all bits as indicated by
prefix length). Otherwise prefixes are encoded as in BGP UPDATE
Raszuk, et al. Expires December 4, 2011 [Page 4]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
messages, a length in bits is followed by enough octets to contain
the prefix information.
Type 3 - Next Header
Encoding: <type (1 octet), [op, value]+>
Contains a set of {operator, value} pairs that are used to match
the last Next Header value octet in IPv6 packets. The operator
byte is encoded as specified in component type 3 of [RFC5575].
While IPv6 allows for more then one Next Header field in the
packet the main goal of Type 3 flow specification component is to
match on the subsequent IP protocol value. Therefor the
definition is limited to match only on last Next Header field in
the packet.
Type 11 - Traffic Class
Encoding: <type (1 octet), [op, value]+>
Contains a set of {operator, value} pairs that are used to match
the Traffic Class 8-bit field [RFC2460] encoded in a single
octet.The operator byte is encoded as specified in component type
3 of [RFC5575].
Type 12 - Fragment - Removed
This type is removed for IPv6 flow specification as in IPv6
fragmentation does not happen in the network.
Type 13 - Flow Label - New type
Encoding: <type (1 octet), [op, value]+>
Contains a set of {operator, value} pairs that are used to match
the 20-bit Flow Label field [RFC2460].The operator byte is encoded
as specified in the component type 3 of [RFC5575].
4. IPv6 Flow Specification Traffic Filtering Action changes
One of the traffic filtering actions which can be expressed by BGP
extended community is defined in [RFC5575] as traffic-marking. This
extended community type is of value: 0x8009.
For the purpose of making it compatible with IPv6 header action
expressed by presence of this extended community has been modified to
Raszuk, et al. Expires December 4, 2011 [Page 5]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
read:
Traffic Marking: The traffic marking extended community instructs a
system to modify the Traffic Class bits of a transiting IPv6 packet
to the corresponding value. This extended community is encoded as a
sequence of 5 zero bytes followed by the 8 bit Traffic Class value
encoded in the 6th byte.
5. Security considerations
No new security issues are introduced to the BGP protocol by this
specification.
6. IANA Considerations
IANA is requested to rename currently defined SAFI 133 and SAFI 134
per [RFC5575] to read:
133 Dissemination of flow specification rules
134 L3VPN dissemination of flow specification rules
IANA is requested to create and maintain a new registry entitled:
"Flow Spec IPv6 Component Types". The following component types have
been registered:
Type 1 - Destination IPv6 Prefix
Type 2 - Source IPv6 Prefix
Type 3 - Next Header
Type 4 - Port
Type 5 - Destination port
Type 6 - Source port
Type 7 - ICMP type
Type 8 - ICMP code
Type 9 - TCP flags
Type 10 - Packet length
Type 11 - Traffic Class
Type 12 - Reserved
Type 13 - Flow Label
7. Acknowledgments
Authors would like to thank Pedro Marques and Hannes Gredler for
their valuable input.
Raszuk, et al. Expires December 4, 2011 [Page 6]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 2460, December 1998.
[RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway
Protocol 4 (BGP-4)", RFC 4271, January 2006.
[RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement
with BGP-4", RFC 5492, February 2009.
[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, August 2009.
8.2. Informative References
[RFC5095] Abley, J., Savola, P., and G. Neville-Neil, "Deprecation
of Type 0 Routing Headers in IPv6", RFC 5095,
December 2007.
Authors' Addresses
Robert Raszuk
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134
US
Email: raszuk@cisco.com
Burjiz Pithawala
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134
US
Email: bpithaw@cisco.com
Raszuk, et al. Expires December 4, 2011 [Page 7]
Internet-Draft draft-ietf-idr-flow-spec-v6 June 2011
Danny McPherson
Verisign, Inc.
Email: dmcpherson@verisign.com
Raszuk, et al. Expires December 4, 2011 [Page 8]