draft-ietf-grow-no-more-unallocated-slash8s-00.txt   draft-ietf-grow-no-more-unallocated-slash8s-01.txt 
Network Working Group L. Vegoda Network Working Group L. Vegoda
Internet-Draft ICANN Internet-Draft ICANN
Intended status: BCP March 12, 2011 Intended status: BCP May 13, 2011
Expires: September 13, 2011 Expires: November 14, 2011
Time to Remove Filters for Previously Unallocated IPv4 /8s Time to Remove Filters for Previously Unallocated IPv4 /8s
draft-ietf-grow-no-more-unallocated-slash8s-00 draft-ietf-grow-no-more-unallocated-slash8s-01
Abstract Abstract
It has been common for network administrators to filter IP traffic It has been common for network administrators to filter IP traffic
coming from unallocated IPv4 address space. Now that there are no from and BGP prefixes of unallocated IPv4 address space. Now that
longer any unallocated IPv4 /8s, this practise is more complicated, there are no longer any unallocated IPv4 /8s, this practise is more
fragile and expensive. Network administrators are advised to remove complicated, fragile and expensive. Network administrators are
filters based on the registration status of the address space. advised to remove filters based on the registration status of the
address space.
This document explains why any remaining filters for unallocated IPv4 This document explains why any remaining packet and BGP prefix
/8s should now be removed on border routers and documents those IPv4 filters for unallocated IPv4 /8s should now be removed on border
unicast prefixes that should not be routed across the public routers and documents those IPv4 unicast prefixes that should not be
Internet. routed across the public Internet.
Status of this Memo Status of this Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 13, 2011. This Internet-Draft will expire on November 14, 2011.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2011 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
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 2, line 18 skipping to change at page 2, line 19
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Traffic Filtering Options . . . . . . . . . . . . . . . . . . . 3 3. Traffic Filtering Options . . . . . . . . . . . . . . . . . . . 3
3.1. No Longer Filtering Based on Address Registration 3.1. No Longer Filtering Based on Address Registration
Status . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Status . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.2. Continuing to Filter Traffic from Unallocated IPv4 3.2. Continuing to Filter Traffic from Unallocated IPv4
Space . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Space . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Prefixes That Should Not be Routed Across the Internet . . . . 4 4. Prefixes That Should Not be Routed Across the Internet . . . . 4
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 5
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5
7. Normative References . . . . . . . . . . . . . . . . . . . . . 5 7. Normative References . . . . . . . . . . . . . . . . . . . . . 5
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 5 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 6
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 5 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction 1. Introduction
It has been common for network administrators to filter IP traffic It has been common for network administrators to filter IP traffic
coming from unallocated IPv4 address space. Now that there are no from and BGP prefixes of unallocated IPv4 address space. Now that
longer any unallocated IPv4 /8s, this practise is more complicated, there are no longer any unallocated IPv4 /8s, this practise is more
fragile and expensive. Network administrators are advised to remove complicated, fragile and expensive. Network administrators are
filters based on the registration status of the address space. advised to remove filters based on the registration status of the
address space.
This document explains why any remaining filters for unallocated IPv4 This document explains why any remaining packet and BGP prefix
/8s should now be removed on border routers and documents those IPv4 filters for unallocated IPv4 /8s should now be removed on border
unicast prefixes that should not be routed across the public routers and documents those IPv4 unicast prefixes that should not be
Internet. routed across the public Internet.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14, RFC 2119 document are to be interpreted as described in BCP 14, RFC 2119
[RFC2119]. [RFC2119].
Bogons are packets sourced from addresses that have not yet been
allocated by IANA or the Regional Internet Registries (RIRs), or
addresses reserved for private or special use by RFCs [RFC3871].
Martians are packets with an altogether bogus (non-registered or ill-
formed) Internet address [RFC1208]. Bogons are referred to as "Dark
IP" in some circles.
3. Traffic Filtering Options 3. Traffic Filtering Options
3.1. No Longer Filtering Based on Address Registration Status 3.1. No Longer Filtering Based on Address Registration Status
Network administrators who implemented filters for unallocated IPv4 Network administrators who implemented filters for unallocated IPv4
/8s did so in the knowledge that those /8s were not a legitimate /8s did so in the knowledge that those /8s were not a legitimate
source of traffic on the Internet and that there was a small number source of traffic on the Internet and that there was a small number
of filters to implement. Now that there are no longer any of bogon filters to implement. Now that there are no longer any
unallocated unicast IPv4 /8s, there will be legitimate Internet unallocated unicast IPv4 /8s, there will be legitimate Internet
traffic coming from all unicast /8s that are not reserved for special traffic coming from all unicast /8s that are not reserved for special
purposes in an RFC. purposes in an RFC.
Removing ingress filters based on the registration status of the IPv4 Removing packet and prefix filters based on the registration status
address is a simple approach that will avoid blocking legitimate of the IPv4 address is a simple approach that will avoid blocking
Internet traffic. legitimate Internet traffic. Network operators SHOULD remove both
ingress and egress packet filters as well as BGP prefix filters for
previously unallocated IPv4 /8s.
3.2. Continuing to Filter Traffic from Unallocated IPv4 Space 3.2. Continuing to Filter Traffic from Unallocated IPv4 Space
Some network administrators might want to continue filtering Some network administrators might want to continue filtering
unallocated IPv4 addresses managed by the Regional Internet unallocated IPv4 addresses managed by the RIRs. This requires
Registries (RIRs). This requires significantly more granular ingress significantly more granular ingress filters and the highly dynamic
filters and the highly dynamic nature of the RIRs' address pools nature of the RIRs' address pools means that filters need to be
means that filters need to be updated on a daily basis to avoid updated on a daily basis to avoid blocking legitimate incoming
blocking legitimate incoming traffic. traffic.
4. Prefixes That Should Not be Routed Across the Internet 4. Prefixes That Should Not be Routed Across the Internet
Network operators who only wish to filter traffic originating from Network operators who only wish to filter traffic originating from
addresses that should never be routed across the Internet can deploy addresses that should never be routed across the Internet, Martians,
a set of ingress filters designed to block traffic from address can deploy a set of packet and prefix filters designed to block
blocks reserved for special purposes. These are: traffic from address blocks reserved for special purposes. These
are:
- 0.0.0.0/8 (Local identification) [RFC1122]; - 0.0.0.0/8 (Local identification) [RFC1122];
- 10.0.0.0/8 (Private use) [RFC1918]; - 10.0.0.0/8 (Private use) [RFC1918];
- 127.0.0.0/8 (Loopback) [RFC1122]; - 127.0.0.0/8 (Loopback) [RFC1122];
- 169.254.0.0/16 (Link local) [RFC3927]; - 169.254.0.0/16 (Link local) [RFC3927];
- 172.16.0.0/12 (Private use) [RFC1918]; - 172.16.0.0/12 (Private use) [RFC1918];
skipping to change at page 5, line 13 skipping to change at page 5, line 25
This document makes no request of IANA. This document makes no request of IANA.
7. Normative References 7. Normative References
[RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5, [RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5,
RFC 1112, August 1989. RFC 1112, August 1989.
[RFC1122] Braden, R., "Requirements for Internet Hosts - [RFC1122] Braden, R., "Requirements for Internet Hosts -
Communication Layers", STD 3, RFC 1122, October 1989. Communication Layers", STD 3, RFC 1122, October 1989.
[RFC1208] Jacobsen, O. and D. Lynch, "Glossary of networking terms",
RFC 1208, March 1991.
[RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and [RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and
E. Lear, "Address Allocation for Private Internets", E. Lear, "Address Allocation for Private Internets",
BCP 5, RFC 1918, February 1996. BCP 5, RFC 1918, February 1996.
[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, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for [RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for
Network Interconnect Devices", RFC 2544, March 1999. Network Interconnect Devices", RFC 2544, March 1999.
[RFC3871] Jones, G., "Operational Security Requirements for Large
Internet Service Provider (ISP) IP Network
Infrastructure", RFC 3871, September 2004.
[RFC3927] Cheshire, S., Aboba, B., and E. Guttman, "Dynamic [RFC3927] Cheshire, S., Aboba, B., and E. Guttman, "Dynamic
Configuration of IPv4 Link-Local Addresses", RFC 3927, Configuration of IPv4 Link-Local Addresses", RFC 3927,
May 2005. May 2005.
[RFC5735] Cotton, M. and L. Vegoda, "Special Use IPv4 Addresses", [RFC5735] Cotton, M. and L. Vegoda, "Special Use IPv4 Addresses",
BCP 153, RFC 5735, January 2010. BCP 153, RFC 5735, January 2010.
[RFC5737] Arkko, J., Cotton, M., and L. Vegoda, "IPv4 Address Blocks [RFC5737] Arkko, J., Cotton, M., and L. Vegoda, "IPv4 Address Blocks
Reserved for Documentation", RFC 5737, January 2010. Reserved for Documentation", RFC 5737, January 2010.
 End of changes. 17 change blocks. 
37 lines changed or deleted 56 lines changed or added

This html diff was produced by rfcdiff 1.41. The latest version is available from http://tools.ietf.org/tools/rfcdiff/