SIDR Working Group D. McPherson
Internet-Draft Verisign, Inc.
Intended status: Standards Track S. Amante
Expires: March 8, 2013 Level 3 Communications
E. Osterweil
Verisign, Inc.
L. Blunk
Merit Network, Inc.
September 4, 2012
IRR & Routing Policy Configuration Considerations
draft-mcpherson-irr-routing-policy-considerations-01
Abstract
The purpose of this document is to catalog past issues influencing
the efficacy of Internet Routing Registries (IRR) for inter-domain
routing policy specification and application in the global routing
system over the past two decades. Additionally, it provides a
discussion regarding which of these issues are still problematic in
practice, and which are simply artifacts that are no longer
applicable but continue to stifle inter-provider policy-based
filtering adoption and IRR utility to this day.
Status of this Memo
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Copyright Notice
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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Background . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Historical Artifacts Influencing IRR Efficacy . . . . . . . . 3
4. Accuracy and Integrity of Data Contained within the IRR . . . 4
4.1. Lack of Resource Certification . . . . . . . . . . . . . . 4
4.2. Incentives to Maintain Data within the IRR . . . . . . . . 4
4.3. Inability for Third Parties to Remove (Stale)
Information from the IRRs . . . . . . . . . . . . . . . . 5
4.4. Lack of Authoritative IRR for Resources . . . . . . . . . 6
4.5. Conclusions with respect to Data in the IRR . . . . . . . 7
5. Operation of the IRR Infrastructure . . . . . . . . . . . . . 7
5.1. Replication of Resources Among IRRs . . . . . . . . . . . 7
5.2. Updating Routing Policies from Updated IRR Resources . . . 8
6. Historical BGP Protocol Limitations . . . . . . . . . . . . . 10
7. Historical Limitations of Routers . . . . . . . . . . . . . . 11
7.1. Incremental Updates to Policy on Routers . . . . . . . . . 11
7.2. Storage Requirements for Policy on Routers . . . . . . . . 12
7.3. Updating Configuration on Routers . . . . . . . . . . . . 12
8. Security Considerations . . . . . . . . . . . . . . . . . . . 13
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
11. Informative References . . . . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
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1. Introduction
The purpose of this document is to catalog past issues influencing
the efficacy of Internet Routing Registries (IRR) for inter-domain
routing policy specification and application in the global routing
system over the past two decades. Additionally, it provides a
discussion regarding which of these issues still pose problems in
practice, and which are no longer obstacles, but whose perceived
drawbacks continue to stifle inter-provider policy-based filtering
support and IRR utility to this day.
2. Background
IRRs can be used to express a multitude of Internet number bindings
and policy objectives, to include bindings between an origin AS and a
given prefix, AS and community import and export policies for a given
AS, as well as AS macros (as-sets in RPSL-speak) that convey the set
of ASes for which a given AS intends to include in some common group.
As quoted from Section 7 of [RFC1787], Routing in a Multi-Provider
Internet:
While ensuring Internet-wide coordination may be more and more
difficult, as the Internet continues to grow, stability and
consistency of the Internet-wide routing could significantly
benefit if the information about routing requirements of various
organizations could be shared across organizational boundaries.
Such information could be used in a wide variety of situations
ranging from troubleshooting to detecting and eliminating
conflicting routing requirements. The scale of the Internet
implies that the information should be distributed. Work is
currently underway to establish depositories of this information
(Routing Registries), as well as to develop tools that analyze, as
well as utilize this information.
3. Historical Artifacts Influencing IRR Efficacy
The term IRR is often used, incorrectly, as a broad catch-all term to
categorize issues related to the accuracy of data in the IRR, the
Routing Policy Specification Language (RPSL) and the operational
deployment of policy (derived from RPSL contained within the IRR) to
routers. It is important to classify these issues into distinct
categories so that the reader can understand which categories of
issues are historical artifacts that are no longer applicable and
which categories of issues still exist and might be addressed by the
IETF.
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The following sections will separate out challenges related to the
IRR into the following categories. First, accuracy and integrity of
data contained within the IRR. Second, the Resource Policy
Specification Language (RPSL) used to represent various types of data
in the IRR. Third, operation of the IRR infrastructure, i.e.:
synchronization of resources from one IRR to other IRRs. Finally,
the methods related to extraction of policy from the IRR and the
input plus activation of that policy within routers.
4. Accuracy and Integrity of Data Contained within the IRR
The following section will examine issues related to accuracy and
integrity of data contained within the IRR.
4.1. Lack of Resource Certification
One of the largest weaknesses often cited with the IRR system is that
the data contained within the IRRs is out of date or lacks integrity.
This is largely attributable to the fact that historically there has
existed no method for developing cryptographically verifiable
bindings of an IP prefix to the originating Autonomous System (AS).
That is, there has never existed a resource certification
infrastructure that enables a resource holder to authorize a
particular autonomous system to originate network layer reachability
advertisements for a given IPv4 or IPv6 prefix. It should be noted
that this is not a weakness of the underlying Routing Policy
Specification Language (RPSL) [RFC2622], but rather, was largely the
result of no infrastructure investment by Internet Number Resource
Registries to provide sufficient resource certification
infrastructure that would enable a resource holder to develop a
cryptographic binding between, for example, a given AS number and an
IP prefix.
4.2. Incentives to Maintain Data within the IRR
A second problem with data contained in the IRRs is that the
incentives for resource holders to maintain both accurate and up-to-
date information in one, or more, IRRs; including deletion of out-of-
date or stale data from the IRRs can diminish rapidly when changing
their peering policies (such as switching transit providers).
Specifically, there is a very strong incentive for an ISP's customers
to register new routing information in the IRR, because some ISP's
enforce a strict policy that they will only build or update a
customer's prefix-lists applied to the customer's inbound eBGP
sessions based off information found within the IRRs. Unfortunately,
there is little incentive for an ISP's customers to remove out-of-
date information from an IRR, most likely attributed to the fact that
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some ISP's do not use, or enforce use of, data contained within the
IRRs to automatically build incoming policy applied to customer's
eBGP sessions. For example, if a customer is terminating service
from one ISP that requires use of IRR data to build incoming policy
and, at the same time, enabling service with another ISP that does
not require use of IRR data, then that customer will likely let the
data in the IRR become stale or inaccurate.
Further, policy filters are almost exclusively generated based on the
origin AS information contained within IRR route objects and used by
providers to filter downstream transit customers. Since providers
only look for route objects containing the origin AS of their
downstream customer(s), stale route objects with historical and,
possibly, incorrect origin AS information are ignored. Assuming that
the downstream customer(s) do not continue to announce those routes
with historical, or incorrect, origin AS information in BGP to the
upstream provider, there is no significant incentive to remove them
as they do not impact offline policy filter generation nor routing on
the Internet. On the other hand, the main incentive that causes the
Service Provider to work with downstream customer(s) is when the
resultant filter list becomes too large that it is difficult for it
to be stored on-board PE routers; however, this is more practically
an operational issue with very old, legacy PE routers, not more
modern PE router hardware with more robust Control Plane Engines.
4.3. Inability for Third Parties to Remove (Stale) Information from the
IRRs
A third challenge with data contained in IRRs is that it is not
possible for IRR operators, and ISP's who use them, to proactively
remove (perceived) out-of-date or "stale" resources in an IRR, on
behalf of resource holders who may not be diligent in maintaining
this information themselves. The reason is that, according to the
Resource Policy Specification Language (RPSL) [RFC2622], only the
resource holder ('mntner') specified in a 'mnt-by' value field of an
RPSL resource is authorized to add, modify or delete their own
resources within the IRR. To address this issue, the 'auth-override'
mechanism [RFC2725] was later developed that would have enabled a
third party to update and/or remove "stale" resources from the IRR.
While it is unclear if this was ever implemented or deployed, it does
provide language semantics needed to overcome this obstacle.
Nevertheless, with such a mechanism in place, there is still a risk
that the original RPSL resource holder would not receive
notifications (via the 'notify' attribute in various RPSL resources)
about the pending or actual removal of a resource from the IRR in
time to halt that action if those resources were still being used.
In this case, if the removal of a resource was not suspended, it
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could potentially result in an unintentional denial of service for
the RPSL resource holder when, for example, ISP's automatically
generated and deployed a new policy based on the newly removed
resources from the IRR, thus dropping any reachability announcement
for the removed resource in eBGP.
4.4. Lack of Authoritative IRR for Resources
According to [RFC2622], within an RPSL resource "the source attribute
specifies the registry where the object is registered." Note that
this source attribute only exists within the RPSL resource itself.
Unfortunately, given a specific resource, (e.g.: a specific IPv4 or
IPv6 prefix), most of the time it is impossible to tell a priori the
authoritative IRR where to query and retrieve an authoritative copy
of that resource.
This makes it difficult for consumers of data from the IRR to
automatically know the authoritative IRR of a resource holder, which
will contain their most up-to-date set of resources. This is
typically not a problem for an ISP that has a direct (customer)
relationship with the resource holder, because the ISP will ask the
resource holder which (authoritative) IRR to pull their resources
from on, for example, a "Customer BGP Order Form". However, third
parties that do not have a direct relationship with the resource
holder, have a difficult time attempting to infer the authoritative
IRR, preferred by the resource holder, that likely contains the most
up-to-date set of resources. As a result, it would be helpful for
third parties if there was a robust referral mechanism so that a
query to one IRR would be automatically redirected toward the
authoritative IRR for the most up-to-date and authoritative copy of
that particular resource. This problem is worked around by
individual IRR operators storing a local copy of other IRR's
resources, through periodic mirroring, which allows the individual
IRR to respond to a client's query with all registered instances of a
particular IRR resource that exist in both the local IRR and all
other IRRs. Of course, the problem with this approach is that an
individual IRR operator is under no obligation to mirror all other
IRRs and, in practice, some IRRs do not mirror the resources from all
other IRRs. This could lead to the false impression that a
particular resource is not registered or maintained at a particular
IRR. Furthermore, the authentication process of accepting updates by
any given IRR may, or may not, be robust enough to overcome
impersonation attacks. As a result, there is no rigorous assurance
that a mirrored RPSL statement was actually made by the authorized
resource holder.
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4.5. Conclusions with respect to Data in the IRR
All of the aforementioned issues related to integrity and accuracy of
data within the IRR stem from a distinct lack of resource
certification for resources contained within the IRR. Only now is an
experimental testbed that reports to provide this function (under the
auspices of the Resource PKI [I-D.ietf-sidr-arch]) being formally
discussed, which could also aid in certification of resources within
the IRR. It should be noted that the RPKI is only currently able to
support signing of Route Origin Authorization (ROA) resources that
are the equivalent of 'route' resources in the IRR. It is unclear
if, in the future, the RPKI will be extended to support additional
resources that already exist in the IRR, e.g.: aut-num, as-net,
route-set, etc. Finally, a seemingly equivalent resource
certification specification for all resources in the IRR has already
been developed [RFC2725], however it is unclear how widely it was
ever implemented or deployed.
5. Operation of the IRR Infrastructure
5.1. Replication of Resources Among IRRs
Currently, several IRRs [IRR_LIST] use a Near-Real-Time Mirroring
(NRTM) protocol to replicate each others contents. However, this
protocol has a several weaknesses. Namely, there is no way to
validate that the copy of mirror is correct and synchronization
issues have often resulted. Furthermore, the NRTM protocol does not
employ any security mechanisms. The NRTM protocol relies on a pull
mechanism and is generally is configured with a poll interval of 5 to
10 minutes. There is currently no mechanism to notify an IRR when an
update has occurred in a mirrored IRR so that an immediate update can
be made.
Some providers employ a process of mirroring an instance of an IRR
that involves downloading a flat text file copy of the IRR that is
made available via FTP. These FTP files are exported at regular
intervals of typically anywhere between 2 and 24 hours by the IRRs.
When a provider fetches those text files, it will process them to
identify any updates and reflect changes within its own internally
maintained database. The use of an internally maintained database is
out-of-scope of this document, but is generally used to assist with
more straightforward access to or modification of data by the IRR
operator. Providers typically employ a 24 hour cycle to pull updated
resources from IRRs. Thus, depending on when resource holders
submitted their changes to an IRR, it may take up to 24 hours for
those changes to be reflected in their policy configurations. In
practice, it appears that the RPKI will also employ a 24 hour cycle
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whereby changes in resources are pushed out to other RPKI caches
[REF?].
IRRs originated from Section 7 of [RFC1787], specifically: "The scale
of the Internet implies that the [routing requirements] information
should be distributed." Regardless, the practical effect of an
organization maintaining its own local cache of IRR resources is an
increase in resource resiliency (due to multiple copies of the same
resource being geographically distributed), a reduction in query time
for resources and, likely, a reduction in bandwidth consumption and
associated costs. This is particularly beneficial when, for example,
an ISP is evaluating resources in an IRR just to determine if there
are any modifications to those resources that will ultimately be
reflected in a new routing policy that will get propagated to (Edge)
routers in the ISP's network. Cache locality results in reduced
bandwidth utilization for each round trip.
On the other hand, it is unclear from where the current provider
replication interval of 24 hours originated or even whether it still
provides enough freshness in the face of available resources,
particularly in today's environment where a typical IRR system
consists of a (multi-core) multi-Ghz CPU connected to a network via a
physical connection of 100 Mbps or, more likely, higher bandwidth.
In addition, it can be observed that the most common circuit size
used by ISP's is now 10 Gbps, thus eliminating bandwidth as a
significant factor in the transfer of data between IRRs.
Furthermore, it should be noted that Merit's Internet Routing
Registry Daemon (IRRd) [MERIT-IRRD], uses 10 minutes as its default
for "irr_mirror_interval".
Lastly, it should be noted that [RFC2769], Routing Policy System
Replication, attempted to offer a more methodical solution for
distributed replication of resources between IRRs. It is unclear why
this RFC failed to gain traction, but it is suspected that this was
due to that specification's reliance on [RFC2725], Routing Policy
System Security, that addressed "the need to assure integrity of the
data by providing an authentication and authorization model."
5.2. Updating Routing Policies from Updated IRR Resources
Ultimately, the length of time it takes to replicate resources among
IRRs is, generally, the dominant factor in reflecting changes to
resources in policy that is eventually applied within the Control
Plane of routers. The length of time to update network elements will
vary considerably depending on the size of the ISP and the number of
IRR resources that were updated during any given interval. However,
there are a variety of common techniques, that are outside the scope
of this document, that allow for this automated process to be
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optimized to considerably reduce the length of time it takes to
update policies in the ISP's network.
An ISP will begin the process of updating the policy in their
network, by first fetching IRR resources associated with, for
example, a customer ASN attached to their network. Next, the ISP
constructs a new policy associated to that customer and then
evaluates if that new policy is different from existing policy
associated with that same customer. If there are no changes between
the new and existing policy associated with that customer, then the
ISP does not make any changes to the policy in their routers specific
to that customer. On the other hand, if the new policy does reflect
changes from the existing policy for that customer, then the ISP
begins a process of uploading the new policy to the routers attached
to that customer.
The process of constructing a new policy involves use of a set of
programs, e.g.: IRRtoolset, that performs recursive expansion of an
RPSL aut-num resource, that comprises an arbitrary combination of
other RPSL aut-num, as-set, route and route-set resources, according
to procedures defined by RPSL. The end result of this process is,
traditionally, a router vendor dependent configuration snippet that
defines the routing policy for that customer. This routing policy
may consist of the set of IPv4 or IPv6 prefixes, associated prefix
lengths and AS_PATH's that are supposed to be accepted from a
customer's eBGP session. However, if indicated in the appropriate
RPSL resource, the policy may also set certain BGP Attributes, such
as MED, AS_PATH prepend value, LOCAL_PREF, etc., at either the
incoming eBGP session from the customer or on static routes that are
originated by the resource holder.
An ISP's customers may not adequately plan for pre-planned
maintenance or, more likely, need to rapidly begin announcing a new
IP prefix as a result of, for example, an emergency turn-up of the
ISP customer's new downstream customer. Unfortunately, the routine,
automated process employed by the ISP means that they may not begin
updating their routing policy on their network for up to 24 hours,
because the ISP or the IRRs the ISP uses might only mirror changes to
IRR resources once every 24 hours. The time interval for the
routine/automated process is not responsive to the needs of directly
paying customer(s) who need rapid changes in their policy in rare
situations. In these situations, when a customer has an urgent need
for updates to take affect immediately, they will call up the Network
Operations Center (NOC) of their ISP and request that the ISP
immediately fetch new IRR objects and push those changes out to their
network. This is often accomplished in as little as five minutes
from the time a customer contacts their ISP's NOC to the time a new
filtering policy is pushed out to the PE routers that are attached to
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that customer's Attachment Circuits (AC's). It is conceivable that
some ISPs automate this using out-of-band mechanisms as well,
although the authors are unaware of any existing mechanisms that
support this.
Ultimately, the aforementioned latency with respect to "emergency
changes" in IRR resources that need to be reflected in near-real-time
in the network is compounded if the IRR resources were being used by
third party ISP's to perform filtering on their peering circuits,
where typically no such policies are employed today for this very
reason. It is likely that the length of time at which IRRs mirror
changes will have to be dramatically reduced with a corresponding
reduction in time at the ISP's that, in turn, need to evaluate
whether changes in a set of IRR resources need to get reflected in
updated router policies that will get pushed out to ASBR's, connected
to peering circuits, on their network.
6. Historical BGP Protocol Limitations
As mentioned previously, after a resource holder made changes to
their resources in an IRR, those changes would automatically be
distributed to other IRRs, ISPs would then learn of those changes,
generate a new BGP policies, and then apply those to the appropriate
subset of routers in their ASes. However, in the past, one
additional step is necessary in order to have any of those new BGP
policies take effect in the Control Plane and to allow/deny the
updated resource from a customer to their ISP and from their
immediately upstream ISP to the ISP's peers. It was necessary (often
manually) to actually induce BGP on each router to apply the new
policy within the Control Plane, thus learning of a newly announced/
changed IP prefix (or, dropping a deleted IP prefix). Unfortunately,
most of these methods were not only highly operationally impactful,
but also affected traffic forwarding to IP destinations that were
unrelated to the most recent changes to the BGP policy.
Historically, a customer would have to (re-)announce the new IP
prefix toward their ISP, but only after the ISP had placed the new
BGP policies into affect. Alternatively, the ISP would have to reset
the entire PE-CE eBGP session either by: a) bouncing the entire
interface toward the customer, (e.g.: shutdown/no shutdown); or, b)
clearing the eBGP session toward the customer, (e.g.: clear ip bgp
neighbor >IP address of CE router<). The latter two cases were, of
course, the most highly impactful and thus could generally only be
performed off-hours during a maintenance window.
Once the new IP prefix has been successfully announced by the
customer and permitted by the newly updated policy at the ISP's PE's
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(attached to that customer), it would be propagated to that ISP's
ASBR's, attached to peers, at the perimeter of the ISP network.
Unfortunately, if those peers had either not yet learned of the
changes to resources in the IRR or pushed out new BGP policies (and,
reset their BGP sessions immediately afterward) incorporating those
changes, then the newly announced route would also get dropped at the
ingress ASBR's of the peers.
Ultimately, either of the two scenarios above further lengthen the
effective time it would take for changes in IRR resources to take
affect within BGP in the network. Fortunately, BGP has been enhanced
over the last several years in order that changes within BGP policy
will take affect without requiring a service impacting reset of BGP
sessions. Specifically, BGP soft-reconfiguration [REF?] and, later,
Route Refresh Capability for BGP-4 [RFC2918] were developed so that
ISPs, or their customers, could induce BGP to apply a new policy
while leaving both the existing eBGP session active as well as
(unaffected) routes active in both the Loc-RIB and, more importantly,
FIB of the router. Thus, using either of these mechanisms, an ISP or
its peers currently will deploy a newly generated BGP policy, based
on changes to resources within the IRR, and immediately trigger a
non-service impacting notification to the BGP process to have those
changes take affect in their Control Plane, either allowing a new IP
prefix to be announced or an old IP prefix to be dropped. This
dramatically reduces the length of time after changes are propagated
throughout the IRRs to when those changes are actually operational
within BGP policy in an ISP's network.
7. Historical Limitations of Routers
7.1. Incremental Updates to Policy on Routers
Routers in the mid 1990's rarely supported incrementally updatable
prefix filters for BGP, and therefore, if new information was
received from a policy or internal configuration database that would
impact a policy applied to a given eBGP peer, the entire prefix list
or access list would need to be deleted and rewritten, compiled, and
installed. This was very tedious and commonly led to leaked routes
during the time when the policy was being rewritten, compiled, and
applied on a router. Furthermore, application of a new policy would
not automatically result in new ingress or egress reachability
advertisements, from that new policy, because routers at the time
would require a reset of the eBGP sessions for routing information to
be evaluated by the new policy. Of course, resetting of an eBGP
session had implications on traffic forwarding during the time the
eBGP session was reestablished and new routing information was
learned.
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Routers now support the ability to perform incremental, and in situ,
updates to filter lists consisting of IP prefixes and/or AS_PATH's
that are used within an ingress or egress BGP policy. In addition,
routers also can apply those incremental updates to policy, with no
traffic disruption, using BGP soft-reconfiguration or BGP Route
Refresh, as discussed in the previous section.
7.2. Storage Requirements for Policy on Routers
Historically, routers had very limited storage capacity and would
have difficulty in storing an extremely large BGP policy on-board.
This was typically the result of router hardware vendors using an
extremely limited amount of NVRAM for storage of router
configurations.
Another challenge with historical router hardware was that writing to
NVRAM was extremely slow. Thus, when the router configuration had
changed as a result of, for example, updating a BGP policy to
accommodate changes in IRR resources, this would result in extremely
long times to write out these configuration changes and, sometimes,
due to bugs would result in loss of protocol keep-alives, thus
causing an impact to routing or forwarding of packets through the
platform.
The above limitations have largely been resolved with more modern
equipment from the last few years shipping with increasing amounts of
non-volatile storage such as: PCMCIA or USB Flash Cards, Hard Disk
Drives or Solid State Disk Drives.
7.3. Updating Configuration on Routers
Historically, there has not been a standardized network configuration
modeling language or an associated method to update router
configurations. When an ISP detected a change in resources within
the IRR, it would fashion a router vendor dependent BGP policy and
upload that to the router usually via the following method.
First, an updated BGP policy configuration 'snippet' is generated via
processes running on an offline server. Next, the operator uses
either telnet or SSH to login to the CLI of a target router and issue
router vendor dependent CLI commands that will trigger the target
router to fetch the new configuration snippet via TFTP, FTP or Secure
Copy (SCP) stored on the offline server. The target router will then
perform syntax checking on that configuration snippet and, if that
passes, merge that configuration snippet into the running
configuration of the router's Control Software. At this point, the
new BGP policy configuration 'snippet' is active within the Control
Plane of the router. One last step remains, which is the operator
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will issue a CLI command to induce the router to perform a "soft
reset", via BGP soft-reconfiguration or BGP Route Refresh, of the
associated BGP session in order to trigger the router to apply the
new policy to routes learned from that BGP session without disrupting
traffic forwarding.
More recently, operators have the ability to use NETCONF/SSH (or,
TLS) from an offline server to push a BGP configuration 'snippet'
from an offline server toward a target router that has that
capability. However, this activity is still dependent on generating,
via the offline server, a router vendor dependent XML configuration
snippet that would get uploaded via SSH or TLS to the target router.
In the future, the ability to upload new Route Origin Authorization
(ROA) information may be provided from the RPKI to routers via the
RPKI-RTR [I-D.ietf-sidr-rpki-rtr] protocol. However, this will not
allow operators the ability to upload other configuration information
such as BGP policy information, such as AS_PATH's, BGP communities,
etc. that might be associated with that ROA information, like they
can from IRR generated BGP policies.
8. Security Considerations
9. IANA Considerations
10. Acknowledgements
TBD.
11. Informative References
[I-D.ietf-sidr-arch]
Lepinski, M. and S. Kent, "An Infrastructure to Support
Secure Internet Routing", draft-ietf-sidr-arch-13 (work in
progress), May 2011.
[I-D.ietf-sidr-rpki-rtr]
Bush, R. and R. Austein, "The RPKI/Router Protocol",
draft-ietf-sidr-rpki-rtr-20 (work in progress),
November 2011.
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Internet-Draft IRR & Routing Policy Considerations September 2012
[MERIT-IRRD]
Merit, "IRRd - Internet Routing Registry Daemon",
http://www.irrd.net.
[RFC1787] Rekhter, Y., "Routing in a Multi-provider Internet",
RFC 1787, April 1995.
[RFC2622] Alaettinoglu, C., Villamizar, C., Gerich, E., Kessens, D.,
Meyer, D., Bates, T., Karrenberg, D., and M. Terpstra,
"Routing Policy Specification Language (RPSL)", RFC 2622,
June 1999.
[RFC2725] Villamizar, C., Alaettinoglu, C., Meyer, D., and S.
Murphy, "Routing Policy System Security", RFC 2725,
December 1999.
[RFC2769] Villamizar, C., Alaettinoglu, C., Govindan, R., and D.
Meyer, "Routing Policy System Replication", RFC 2769,
February 2000.
[RFC2918] Chen, E., "Route Refresh Capability for BGP-4", RFC 2918,
September 2000.
Authors' Addresses
Danny McPherson
Verisign, Inc.
Email: dmcpherson@verisign.com
Shane Amante
Level 3 Communications
1025 Eldorado Blvd
Broomfield, CO 80021
USA
Email: shane@level3.net
Eric Osterweil
Verisign, Inc.
Email: eosterweil@verisign.com
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Internet-Draft IRR & Routing Policy Considerations September 2012
Larry J. Blunk
Merit Network, Inc.
Email: ljb@merit.edu
McPherson, et al. Expires March 8, 2013 [Page 15]
