[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Nits]

Versions: 00 01 02 draft-ietf-opsec-bgp-security

Internet Engineering Task Force                                J. Durand
Internet-Draft                                       CISCO Systems, Inc.
Intended status: BCP                                        I. Pepelnjak
Expires: September 3, 2012                                           NIL
                                                              G. Doering
                                                                SpaceNet
                                                           March 2, 2012


                      BGP operations and security
                   draft-jdurand-bgp-security-00.txt

Abstract

   This documents describes best current practices to manage securely
   BGP in a network.  It will explain the basic policies ones should
   configure on BGP peerings to keep an healthy BGP table.  This
   document will only focus on unicast and multicast tables (SAFI 1 and
   2) for IPv4 and IPv6.

Foreword

   A placeholder to list general observations about this document.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [1].

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 September 3, 2012.

Copyright Notice



Durand, et al.          Expires September 3, 2012               [Page 1]

Internet-Draft                  BGP OPSEC                     March 2012


   Copyright (c) 2012 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
   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.  Definitions  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Protection of BGP sessions . . . . . . . . . . . . . . . . . .  3
     3.1.  MD5 passwords on BGP peerings  . . . . . . . . . . . . . .  3
     3.2.  BGP TTL security . . . . . . . . . . . . . . . . . . . . .  3
   4.  Prefix filtering . . . . . . . . . . . . . . . . . . . . . . .  4
     4.1.  Definition of prefix filters . . . . . . . . . . . . . . .  4
       4.1.1.  Prefixes that are not routable by definition . . . . .  4
       4.1.2.  Prefixes not allocated . . . . . . . . . . . . . . . .  5
       4.1.3.  Prefixes too specific  . . . . . . . . . . . . . . . .  7
       4.1.4.  Anti-spoofing filters  . . . . . . . . . . . . . . . .  8
       4.1.5.  Exchange point LAN prefixes  . . . . . . . . . . . . .  8
       4.1.6.  Default route  . . . . . . . . . . . . . . . . . . . .  8
     4.2.  Prefix filtering recommendations in full routing
           networks . . . . . . . . . . . . . . . . . . . . . . . . .  8
       4.2.1.  Filters with internet peers  . . . . . . . . . . . . .  8
       4.2.2.  Filters with customers . . . . . . . . . . . . . . . . 10
       4.2.3.  Filters with upstream providers  . . . . . . . . . . . 11
     4.3.  Prefix filtering recommendations for leaf networks . . . . 11
       4.3.1.  Ingress filtering  . . . . . . . . . . . . . . . . . . 11
       4.3.2.  Egress filtering . . . . . . . . . . . . . . . . . . . 12
   5.  BGP route flap dampening . . . . . . . . . . . . . . . . . . . 12
   6.  Maximum prefixes on a peering  . . . . . . . . . . . . . . . . 12
   7.  AS-path filtering  . . . . . . . . . . . . . . . . . . . . . . 12
   8.  BGP community scrubbing  . . . . . . . . . . . . . . . . . . . 13
   9.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
   10. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 14
   11. Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     12.1. Normative References . . . . . . . . . . . . . . . . . . . 14
     12.2. Informative References . . . . . . . . . . . . . . . . . . 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15



Durand, et al.          Expires September 3, 2012               [Page 2]

Internet-Draft                  BGP OPSEC                     March 2012


1.  Introduction

   BGP [6] is the protocol used in the internet to exchange routing
   information between network domains.  This protocol does not directly
   include mechanisms that control that routes exchanged conform to the
   various rules defined by the Internet community.  This document
   intends to summarize most common existing rules and help network
   administrators applying simply coherent BGP policies.


2.  Definitions

   o  BGP peering: any TCP BGP connection on the Internet.


3.  Protection of BGP sessions

3.1.  MD5 passwords on BGP peerings

   BGP sessions can be secured with MD5 passwords [8], to protect
   against attacks that could bring down the session (by sending spoofed
   TCP RST packets) or possibly insert packets into the TCP stream
   (routing attacks).

   The drawback of TCP/MD5 is additional management overhead for
   password maintenance.  MD5 protection is recommended when peerings
   are established over shared networks where spoofing can be done (like
   internet exchanges, IXPs).

   You should block spoofed packets (packets with source IP address
   belonging to your IP address space) at all edges of your network,
   making TCP/MD5 protection of BGP sessions unnecessary on iBGP session
   or EBGP sessions run over point-to-point links.

3.2.  BGP TTL security

   BGP sessions can be made harder to spoof with the TTL security -
   instead of sending TCP packets with TTL value = 1, the routers send
   the TCP packets with TTL value = 255 and the receiver checks that the
   TTL value equals 255.  Since it's impossible to send an IP packet
   with TTL = 255 to a non-directly-connected IP host, BGP TTL security
   effectively prevents all spoofing attacks coming from third parties
   not directly connected to the same subnet as the BGP-speaking
   routers.

   Note: Like MD5 protection, TTL security has to be configured on both
   ends of a BGP session.




Durand, et al.          Expires September 3, 2012               [Page 3]

Internet-Draft                  BGP OPSEC                     March 2012


4.  Prefix filtering

   The main aspect of securing BGP resides in controlling the prefixes
   that are received/advertised on the BGP peerings.  Prefixes exchanged
   between BGP peers are controlled with inbound and outbound filters
   that can match on IP prefixes (prefix filters, Section 4), AS paths
   (as-path filters, Section 7) or any other attributes of a BGP prefix
   (for example, BGP communities, Section 8).

4.1.  Definition of prefix filters

   This section list the most commonly used prefix filters.  Following
   sections will clarify where these filters should be applied.

4.1.1.  Prefixes that are not routable by definition

4.1.1.1.  IPv4

   RFC3330 [12] clarifies "special" IPv4 prefixes and their status in
   the Internet.  Following prefixes MUST NOT cross network boundaries
   (ie.  ASN) and therefore MUST be filtered:

   o  10.0.0.0/8 and more specific - private use

   o  169.254.0.0/16 and more specific - link-local

   o  172.0.0.0/8 and more specific - loopbacks

   o  172.16.0.0/12 and more specific - private use

   o  192.0.2.0/24 and more specific- documentation

   o  192.168.0.0/16 and more specific - private use

   o  224.0.0.0/4 and more specific - multicast

   o  240.0.0.0/4 and more specific - reserved

4.1.1.2.  IPv6

   There is no equivalent of RFC3300 for IPv6.  This document recalls
   the prefixes that MUST not cross network boundaries and therefore
   MUST be filtered:

   o  2001:DB8::/32 and more specific - documentation [13]

   o  Prefixes more specific than 2002::/16 - 6to4 [3]




Durand, et al.          Expires September 3, 2012               [Page 4]

Internet-Draft                  BGP OPSEC                     March 2012


   o  3FFE::/16 and more specific - was initially used for the 6Bone
      (worldwide IPv6 test network) and returned to IANA.

   o  FC00::/7 and more specific - ULA (Unique Local Addresses) [5]

   o  FE80::/10 and more specific - link-local addresses [7]

   o  FEC0::/10 and more specific - initially reserved for unicast site-
      local addresses [4].  As some networks may still use it for
      private addressing it is worth considering it when filtering
      private prefixes.

   o  FF00::/8 and more specific - multicast

   The list of IPv6 prefixes that MUST not cross network boundaries can
   be simplified as follows:

   o  2001:DB8::/32 and more specific - documentation [13]

   o  Prefixes more specific than 2002::/16 - 6to4 [3]

   o  All prefixes that are outside 2000::/3 prefix

4.1.2.  Prefixes not allocated

   IANA allocates prefixes to RIRs which in turn allocate prefixes to
   LIRs.  It is wise not to accept in the routing table prefixes that
   are not allocated.  This could mean allocation made by IANA and/or
   allocations done by RIRs.  This section details the options for
   building list of allocated prefixes at every level.

4.1.2.1.  IANA allocated prefixes filters

   IANA has allocated all the IPv4 available space.  Therefore there is
   no reason why one would keep checking prefixes are in the IANA
   allocated address space [19].  No specific filter need to be put in
   place by administrators who want to make sure that IPv4 prefixes they
   receive have been allocated by IANA.

   For IPv6, given the size of the address space, it can be seen as wise
   accepting only prefixes derived from those allocated by IANA.
   Administrators can dynamically build this list from the IANA
   allocated IPv6 space [20].  As IANA keeps allocating prefixes to
   RIRs, the aforementioned list should be checked regularly against
   changes and if they occur, prefix filter should be computed and
   pushed on network devices.  As there is delay between the time a RIR
   receives a new prefix and the moment it starts allocating portions of
   it to its LIRs, there is no need doing this step quickly and



Durand, et al.          Expires September 3, 2012               [Page 5]

Internet-Draft                  BGP OPSEC                     March 2012


   frequently.  At least process in place should make sure there is no
   more than one month between the time the IANA IPv6 allocated prefix
   list changes and the moment all IPv6 prefix filters have been
   updated.

4.1.2.2.  RIR allocated prefixes filters

   A more precise check can be performed as one would like to make sure
   that prefixes they receive are being originated by the autonomous
   system which actually own the prefix.  It has been observed in the
   past that one could easily advertise someone else's prefix (or more
   specific prefixes) and create black holes or security threats.  To
   overcome that risk, administrators would need to make sure BGP
   advertisements correspond to information located in the existing
   registries.  At this stage 2 options can be considered (short and
   long term options).  They are described in the following subsections.

4.1.2.3.  Prefix filters creation from RIR database

   This option consists in using RIR database information for building
   for a given BGP neighbor a list of prefixes and the list of prefix
   with corresponding originating autonomous system.  This can be done
   relatively easily using scripts and existing tools capable of
   retrieving this information in the registries.  This approach is
   exactly the same for both IPv4 and IPv6.

   The macro-algorithm for the script is described as follows.  For the
   peer that is considered, the distant network administrator has
   provided the autonomous system and may be able to provide an AS-SET
   object (aka AS-MACRO).  An AS-SET is an object which contains AS
   numbers or other AS-SET's.  An operator may create an AS-SET defining
   all the AS numbers of its customers.  A tier 1 transit provider might
   create an AS-SET describing the AS-SET of connected operators, which
   in turn describe the AS numbers of their customers.  Using recursion,
   it is possible to retrieve from an AS-SET the complete list of AS
   numbers that the peer is susceptible to announce.  For each of these
   AS numbers, it is also easy to check in the corresponding RIR
   database all associated prefixes.  With these 2 mechanisms a script
   can build for a given peer the list of allowed prefixes and the AS
   number from which they should be originated.

   As prefixes, AS numbers and AS-SET's may not all be under the same
   RIR authority, a difficulty resides choosing for each object the
   appropriate database to poll.  Some registries have been created and
   are not restricted to a given region or authoritative RIR.  They
   allow RIRs to publish their information in a common place.  They also
   make it possible for any subscriber (probably under contract) to
   publish information too.  When doing requests inside such a database,



Durand, et al.          Expires September 3, 2012               [Page 6]

Internet-Draft                  BGP OPSEC                     March 2012


   it is possible to specify the source of information in order to have
   the most reliable data.  One could check the central registry and
   only check that the source is one of the 5 RIRs.  The probably most
   famous registry of that kind is the RADB [21] (Routing Assets
   Database).

   As objects in RIRs DB may quickly vary over time, it is important
   that prefix filters computed using this mechanism are refreshed
   regularly.  A daily basis could even been considered as some routing
   changes must be done sometimes in a certain emergency and registries
   may be updated at the very last moment.  It has to be noted that this
   approach significantly increases the complexity of the router
   configurations as it can quickly add more than ten thousands
   configuration lines for some important peers.

4.1.2.4.  SIDR - Secure Inter Domain Routing

   IETF has created a working group called SIDR (Secure Inter-Domain
   Routing) in order to create an architecture to secure internet
   advertisements.  At the time this document is written, many document
   has been published and a framework is proposed so that advertisements
   can be checked against signed routing objects in RIR routing
   registries.  Implementing mechanisms proposed by this working group
   is the solution that will solve at a longer term the BGP routing
   security.  But as it may take time objects are signed and deployments
   are done such a solution will need to be combined at the time being
   with other mechanisms proposed in this document.  The rest of this
   section assumes the reader understands all technologies associated
   with SIDR.

   Each received route on a router should be checked against the RPKI
   data set: if a corresponding ROA is found and is valid then the
   prefix should be accepted.  It the ROA is found and is INVALID then
   the prefix should be discarded.  If an ROA is not found then the
   prefix should be accepted but corresponding route should be given a
   low preference.

4.1.3.  Prefixes too specific

4.1.3.1.  IPv4

   Prefixes longer than /24 are usually not announced in the IPv4
   internet [16]

4.1.3.2.  IPv6

   Prefixes longer than /48 are usually not announced in the IPv6
   internet [17]



Durand, et al.          Expires September 3, 2012               [Page 7]

Internet-Draft                  BGP OPSEC                     March 2012


4.1.4.  Anti-spoofing filters

   Filtering its own prefixes on peerings with all peers (ingress
   direction) is a protection against spoofing attacks.  Such filters
   must be defined with caution as they can break existing redundancy
   mechanisms.  For example in case an operator has a multihomed
   customer, it should keep accepting the customer prefix from its peers
   and upstreams.  This will make it possible for the customer to keep
   accessing its operator network (and other customers) via the internet
   in case the BGP peering between the customer and the operator is
   down.

4.1.5.  Exchange point LAN prefixes

   When a network is present on an exchange point, it must make sure it
   doesn't receive exchange point LAN prefix and more specifics from any
   of its BGP peers.

4.1.6.  Default route

4.1.6.1.  IPv4

   0.0.0.0/0 prefix MUST NOT be announced on the Internet but it is
   usually exchanged on upstream/customer peerings.

4.1.6.2.  IPv6

   ::/0 prefix MUST NOT be announced on the Internet but it is usually
   exchanged on upstream/customer peerings.

4.2.  Prefix filtering recommendations in full routing networks

   For networks that have the full internet BGP table, some policies
   should be applied on each BGP peer for received and advertised
   routes.  It is recommended that each autonomous filter configures
   rules for advertised and received routes at all its borders as this
   will protect the network and its peer even in case of
   misconfiguration.  The most commonly used filtering policy is
   proposed in this section.

4.2.1.  Filters with internet peers

4.2.1.1.  Ingress filtering

   There are basically 2 options, the loose one where no check will be
   done against RIR allocations and the strict one where it will be
   verified that announcements strictly conform to what is declared in
   routing registries.



Durand, et al.          Expires September 3, 2012               [Page 8]

Internet-Draft                  BGP OPSEC                     March 2012


4.2.1.1.1.  Ingress filtering loose option

   In that case, the following prefixes received from a BGP peer will be
   filtered:

   o  Prefixes not routable (Section 4.1.1)

   o  Prefixes not allocated by IANA (IPv6 only) (Section 4.1.2.1)

   o  Routes too specific (Section 4.1.3)

   o  Self prefixes (Section 4.1.4)

   o  Exchange points LAN prefixes (Section 4.1.5)

   o  Default route (Section 4.1.6)

4.2.1.1.2.  Ingress filtering strict option

   In that case, filters are applied to make sure advertisements
   strictly conform to what is declared in routing registries
   Section 4.1.2.2.  It must be checked that in case of script failure
   all routes are rejected.

   In addition to this, one could apply following filters beforehand in
   case routing registry used as source of information by the script is
   not fully trusted:

   o  Prefixes not routable (Section 4.1.1)

   o  Routes too specific (Section 4.1.3)

   o  Self prefixes (Section 4.1.4)

   o  Exchange points LAN prefixes (Section 4.1.5)

   o  Default route (Section 4.1.6)

4.2.1.2.  Egress filtering

   Configuration in place will make sure that only appropriate prefixes
   are sent.  These can be for example prefixes belonging to the
   considered networks and those of its customers.  This can be done
   using BGP communities or many other solution.  Whatever scenario
   considered, it can be desirable that following filters are positioned
   before to avoid unwanted route announcement due to bad configuration:





Durand, et al.          Expires September 3, 2012               [Page 9]

Internet-Draft                  BGP OPSEC                     March 2012


   o  Prefixes not routable (Section 4.1.1)

   o  Routes too specific (Section 4.1.3)

   o  Exchange points LAN prefixes (Section 4.1.5)

   o  Default route (Section 4.1.6)

   In case it is possible to list the prefixes to be advertised, then
   just configuring the list of allowed prefixes and denying the rest is
   sufficient.

4.2.2.  Filters with customers

4.2.2.1.  Ingress filtering

   Ingress policy with end customers is pretty straightforward: only
   customers prefixes must be accepted, all others should be discarded.
   The list of accepted prefixes can be manually specified, after having
   verified that they are valid.  This validation can be done with the
   appropriate IP address management authorities.  For example one will
   not accept a prefix if it is in a PA (Provider Aggregateable) block.

   Same rules apply in case the customer is also a network connecting
   other customers (for example a tier 1 transit provider connecting
   service providers).  An exception can be envisaged in case it is
   known that the customer network applies strict ingress/egress
   filtering, and the number of prefixes announced by that network is
   too large to list them in the router configuration.  In that case
   filters as in Section 4.2.1.1 can be applied.

4.2.2.2.  Egress filtering

   Egress policy with customers may vary according to the routes
   customer wants to receive.  In the simplest possible scenario,
   customer wants to receive only the default route, which can be done
   easily by applying a filter with the default route only.

   In case the customer wants to receive the full routing (in case it is
   multihomed or if wants to have a view on the internet table), the
   following filters can be simply applied on the BGP peering:

   o  Prefixes not routable (Section 4.1.1)

   o  Routes too specific (Section 4.1.3)

   o  Default route (Section 4.1.6)




Durand, et al.          Expires September 3, 2012              [Page 10]

Internet-Draft                  BGP OPSEC                     March 2012


   There can be a difference for the default route that can be announced
   to the customer in addition to the full BGP table.  This can be done
   simply by removing the filter for the default route.  As the default
   route may not be present in the routing table, one may decide to
   originate it only for peerings where it has to be advertised.

4.2.3.  Filters with upstream providers

4.2.3.1.  Ingress filtering

   In case the full routing table is desired from the upstream, the
   prefix filtering to apply is more or less the same than the one for
   peers Section 4.2.1.1.  There can be a difference for the default
   route that can be desired from an upstream provider even if it
   advertises the full BGP table.  In case the upstream provider is
   supposed to announce only the default route, a simple filter will be
   applied to accept only the default prefix and nothing else.

4.2.3.2.  Egress filtering

   The filters to be applied should not differ from the ones applied for
   internet peers (Section 4.2.1.2).

4.3.  Prefix filtering recommendations for leaf networks

4.3.1.  Ingress filtering

   The leaf network will position the filters corresponding to the
   routes it is requesting from its upstream.  In case a default route
   is requested, simple inbound filter will be applied to accept only
   that default route (Section 4.1.6).  In case the leaf network is not
   capable of listing the prefix because the amount is too large (for
   example if it requires the full internet routing table) then it
   should configure filters to avoid receiving bad announcements from
   its upstream:

   o  Prefixes not routable (Section 4.1.1)

   o  Routes too specific (Section 4.1.3)

   o  Self prefixes (Section 4.1.4)

   o  Default route (Section 4.1.6) depending if the route is requested
      or not







Durand, et al.          Expires September 3, 2012              [Page 11]

Internet-Draft                  BGP OPSEC                     March 2012


4.3.2.  Egress filtering

   A leaf network will most likely have a very straightforward policy:
   it will only announce its local routes.  It can also configure the
   following prefixes filters described in Section 4.2.1.2 to avoid
   announcing invalid routes to its upstream provider.


5.  BGP route flap dampening

   BGP route flap dampening mechanism makes it possible to give
   penalties to routes each time they change in the BGP routing table.
   Initially this mechanism was created to protect the entire internet
   from multiple events impacting a single network.  RIPE community now
   recommends not using BGP route flap dampening [15].  Author of this
   document proposes to follow the proposal of the RIPE community.


6.  Maximum prefixes on a peering

   It is recommended to configure a limit on the number of routes to be
   accepted from a peer.  Following rules are generally recommended:

   o  From peers, it is recommended to have a limit lower than the
      number of routes in the internet.  This will shut down the BGP
      peering if the peer suddenly advertises the full table.  One can
      also configure different limits for each peer, according to the
      number of routes they are supposed to advertise.

   o  From upstreams which provide full routing, it is recommended to
      have a limit much higher than the number of routes in the
      internet.  A limit is still useful in order to protect the network
      (and in particular the routers' memory) if too many routes are
      sent by the upstream.  The limit should be chosen according to the
      number of routes that can actually be handled by routers.

   It is important to review regularly the limits that are configured as
   the internet can quickly change over time.  Some vendors propose
   mechanisms to have 2 thresholds: while the higher number specified
   will shutdown the peering, the first threshold will only trigger a
   log and can be used to passively adjust limits based on observations
   made on the network.


7.  AS-path filtering

   The following rules should be applied on BGP AS-paths:




Durand, et al.          Expires September 3, 2012              [Page 12]

Internet-Draft                  BGP OPSEC                     March 2012


   o  Do not accept anything other than customer's AS number from the
      customer.  Alternatively, only accept AS-paths with a single AS
      number (potentially repeated several times) from your customers.
      The latter option is easier to configure than per-customer AS-path
      filters: the default BGP logic will make sure in that case that
      the first AS number in the AS-path is the one of the peer.

   o  Do not accept overly long AS path prepending from the customer.

   o  Do not accept more than two distinct AS path numbers in the AS
      path if your customer is an ISP with customers.  This rule becomes
      useless in case prefix filters are built from registries as
      described in Section 4.1.2.3.

   o  Do not advertise prefixes with non-empty AS-path if you're not
      transit.

   o  Do not advertise prefixes with upstream AS numbers in the AS path
      to your peering AS.

   o  Do not accept private AS numbers except from customers

   o  Do not advertise private AS numbers.  Exception: Customers using
      BGP without having their own AS number must use private AS numbers
      to advertise their prefixes to their upstream.  The private AS
      number is usually provided by the upstream.

   o  Do not accept prefixes when the first AS number in the AS-path is
      not the one of the peer.  In case the peering is done toward a BGP
      route-server [23] (connection on an Internet eXchange Point - IXP)
      with transparent AS path handling, this verification needs to be
      de-activated as the first AS number will be the one of an IXP
      member whereas the peer AS number will be the one of the BGP
      route-server.


8.  BGP community scrubbing

   Optionally we can consider the following rules on BGP AS-paths:

   o  Scrub inbound communities with your AS number in the high-order
      bits - allow only those communities that customers/peers can use
      as a signaling mechanism

   o  Do not remove other communities: your customers might need them to
      communicate with upstream providers.  In particular do not
      (generally) remove the no-export community as it is usually
      announced by your peer for a certain purpose.



Durand, et al.          Expires September 3, 2012              [Page 13]

Internet-Draft                  BGP OPSEC                     March 2012


9.  Acknowledgements

   A placeholder to acknowledge contributors.


10.  IANA Considerations

   This memo includes no request to IANA.


11.  Security Considerations

   This document is entirely about BGP operational security.


12.  References

12.1.  Normative References

   [1]   Bradner, S., "Key words for use in RFCs to Indicate Requirement
         Levels", BCP 14, RFC 2119, March 1997,
         <http://xml.resource.org/public/rfc/html/rfc2119.html>.

   [2]   Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
         June 1999.

   [3]   Carpenter, B. and K. Moore, "Connection of IPv6 Domains via
         IPv4 Clouds", RFC 3056, February 2001.

   [4]   Huitema, C. and B. Carpenter, "Deprecating Site Local
         Addresses", RFC 3879, September 2004.

   [5]   Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
         Addresses", RFC 4193, October 2005.

   [6]   Rekhter, Y., Li, T., and S. Hares, "A Border Gateway Protocol 4
         (BGP-4)", RFC 4271, January 2006.

   [7]   Hinden, R. and S. Deering, "IP Version 6 Addressing
         Architecture", RFC 4291, February 2006.

   [8]   Touch, J., Mankin, A., and R. Bonica, "The TCP Authentication
         Option", RFC 5925, June 2010.

12.2.  Informative References

   [9]   Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and E.
         Lear, "Address Allocation for Private Internets", BCP 5,



Durand, et al.          Expires September 3, 2012              [Page 14]

Internet-Draft                  BGP OPSEC                     March 2012


         RFC 1918, February 1996.

   [10]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
         Specifications: ABNF", RFC 2234, November 1997.

   [11]  Ferguson, P. and D. Senie, "Network Ingress Filtering:
         Defeating Denial of Service Attacks which employ IP Source
         Address Spoofing", BCP 38, RFC 2827, May 2000.

   [12]  IANA, "Special-Use IPv4 Addresses", RFC 3330, September 2002.

   [13]  Huston, G., Lord, A., and P. Smith, "IPv6 Address Prefix
         Reserved for Documentation", RFC 3849, July 2004.

   [14]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
         Specifications: ABNF", RFC 4234, October 2005.

   [15]  Smith, P. and C. Panigl, "RIPE-378 - RIPE Routing Working Group
         Recommendations On Route-flap Damping", May 2006.

   [16]  Smith, P., Evans, R., and M. Hughes, "RIPE-399 - RIPE Routing
         Working Group Recommendations on Route Aggregation",
         December 2006.

   [17]  Smith, P. and R. Evans, "RIPE-532 - RIPE Routing Working Group
         Recommendations on IPv6 Route Aggregation", November 2011.

   [18]  Doering, G., "IPv6 BGP Filter Recommendations", November 2009,
         <http://www.space.net/~gert/RIPE/ipv6-filters.html>.

   [19]  "IANA IPv4 Address Space Registry", <http://www.iana.org/
         assignments/ipv4-address-space/ipv4-address-space.xml>.

   [20]  "IANA IPv6 Address Space Registry", <http://www.iana.org/
         assignments/ipv6-unicast-address-assignments/
         ipv6-unicast-address-assignments.xml>.

   [21]  "Routing Assets Database", <http://www.radb.net>.

   [22]  "Secure Inter-Domain Routing IETF working group",
         <http://datatracker.ietf.org/wg/sidr/>.

   [23]  "Internet Exchange Route Server", <http://tools.ietf.org/id/
         draft-jasinska-ix-bgp-route-server-03.txt>.







Durand, et al.          Expires September 3, 2012              [Page 15]

Internet-Draft                  BGP OPSEC                     March 2012


Authors' Addresses

   Jerome Durand
   CISCO Systems, Inc.
   11 rue Camille Desmoulins
   Issy-les-Moulineaux  92782 CEDEX
   FR

   Email: jerduran@cisco.com


   Ivan Pepelnjak
   NIL Data Communications
   Tivolska 48
   Ljubljana  1000
   Slovenia

   Email: ip@nil.com


   Gert Doering
   SpaceNet AG
   Joseph-Dollinger-Bogen 14
   Muenchen  D-80807
   Germany

   Email: gert@space.net
























Durand, et al.          Expires September 3, 2012              [Page 16]


Html markup produced by rfcmarkup 1.109, available from https://tools.ietf.org/tools/rfcmarkup/