Opsec Working Group J. Gill
Internet-Draft Verizon Business
Intended status: Informational D. Lewis
Expires: March 4, 2007 P. Quinn
Cisco Systems Inc.
P. Schoenmaker
NTT America
August 31, 2006
Service Provider Infrastructure Security
draft-ietf-opsec-infrastructure-security-00
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Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
This RFC describes best current practices for implementing Service
Provider network infrastructure protection for network elements.
This RFC complements and extends RFC 2267 and RFC 3704. RFC 2267
provides guidelines for filtering traffic on the ingress to service
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provider networks. RFC 3704 expands the recommendations described in
RFC 2267 to address operational filtering guidelines for single and
multi-homed environments. The focus of those RFCs is on filtering
packets on ingress to a network, regardless of destination, if those
packets have a spoofed source address, or if the source address fall
within "reserved" address space. Deployment of RFCs 2267 and 3704
has limited the effects of denial of service attacks by dropping
ingress packets with spoofed source addresses, which in turn offers
other benefits by ensuring that packets coming into a network
originate from validly allocated and consistent sources. This
document focuses solely on traffic destined to elements of the the
network infrastructure itself. This document presents techniques
that, together with network edge ingress filtering and RFC 2267 and
RFC 3704, provides a defense in depth approach for infrastructure
protection. This document does not present recommendations for
protocol validation (i.e. "sanity checking") nor does it address
guidelines for general security configuration.
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 [RFC2119].
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Overview of Infrastructure Protection Techniques . . . . . . . 5
2.1. Edge Remarking . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Device and Element Protection . . . . . . . . . . . . . . 5
2.3. Infrastructure Hiding . . . . . . . . . . . . . . . . . . 5
3. Edge Infrastructure Access Control Lists . . . . . . . . . . . 6
3.1. Constructing the Access List . . . . . . . . . . . . . . . 6
3.2. Other Traffic . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Edge Infrastructure Conclusion . . . . . . . . . . . . . . 7
4. Edge Rewrite/Remarking . . . . . . . . . . . . . . . . . . . . 7
4.1. Edge Rewrite/Remarking Discussion . . . . . . . . . . . . 7
4.2. Edge Rewriting/Remarking Performance Considerations . . . 8
5. Device/Element Protection . . . . . . . . . . . . . . . . . . 8
5.1. Service Specific Access Control . . . . . . . . . . . . . 8
5.1.1. Common Services . . . . . . . . . . . . . . . . . . . 9
5.2. Aggregate Device Access Control . . . . . . . . . . . . . 9
5.2.1. IP Fragments . . . . . . . . . . . . . . . . . . . . . 9
5.2.2. Performance Considerations . . . . . . . . . . . . . . 9
5.2.3. Access Control Implementation Guide . . . . . . . . . 9
5.3. Device Access Authorization and Accounting . . . . . . . . 10
6. Infrastructure Hiding . . . . . . . . . . . . . . . . . . . . 10
6.1. Use Less IP . . . . . . . . . . . . . . . . . . . . . . . 10
6.2. MPLS Techniques . . . . . . . . . . . . . . . . . . . . . 10
6.3. IGP Configuration . . . . . . . . . . . . . . . . . . . . 11
6.4. Route Advertisement Control . . . . . . . . . . . . . . . 11
6.4.1. Route Announcement Filtering . . . . . . . . . . . . . 11
6.4.2. Address Core Out of RFC 1918 Space . . . . . . . . . . 11
6.5. Further obfuscation . . . . . . . . . . . . . . . . . . . 12
7. IPv6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7.1. Use LIPv6 Edge Infrastructure Access Control Lists . . . . 12
7.2. IPv6 Edge Remarking . . . . . . . . . . . . . . . . . . . 12
7.3. IPv6 Device and Element Protection . . . . . . . . . . . . 13
7.4. IPv6 Infrastructure Hiding . . . . . . . . . . . . . . . . 13
8. IP Multicast . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.1. Multicast Group Protection . . . . . . . . . . . . . . . . 13
8.2. Performance Considerations . . . . . . . . . . . . . . . . 14
8.3. IPv6 and Multicast . . . . . . . . . . . . . . . . . . . . 14
9. Security Considerations . . . . . . . . . . . . . . . . . . . 14
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
10.1. Normative References . . . . . . . . . . . . . . . . . . . 14
10.2. Informative References . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
Intellectual Property and Copyright Statements . . . . . . . . . . 16
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1. Introduction
This RFC describes best current practices for implementing Service
Provider network infrastructure protection for network elements. RFC
2267 and RFC 3704 focuses on limiting the effects of denial of
service attacks by filtering ingress packets with spoofed source
addresses. This offers additional benefits by ensuring that packets
coming into a network originate from validly allocated and consistent
sources. RFC 3704 extends the recommendations described in RFC 2267
to address operational filtering guidelines for single and multi-
homed environments. In both cases (RFC 2267 and RFC 3704), the focus
is on dropping packets on ingress, regardless of destination, if
those packets are have a spoofed source address or if the source of
the packet falls within "reserved" address space. This document both
refines and extends the filtering best practices outlined in RFC 2267
and RFC 3704 and focuses only on traffic destined to the network
infrastructure itself to protect the service provider network from
denial of service and other attacks. This document presents
techniques that, together with network edge ingress filtering and RFC
2267 and RFC 3704, provides a defense in depth approach for
infrastructure protection. Denial of Service (DoS) attacks are
common and the network infrastructure itself is a target.
Attacks targeting the network infrastructure can take many forms,
including bandwidth saturation to crafted packets destined to a
router. These attacks might use spoofed source addresses or they
might use the true source address of of the traffic. Regardless of
the nature of the attack, the network infrastructure must be
protected from both accidental floods and intentional attacks.
Additionally, this protection will assist in preventing the network
elements from being used as reflectors in attacks against others.
The techniques outlined in this document and described in section 2
below, describe best practices for infrastructure protection: edge
policy (filtering and precedence), per device traffic policy
enforcement for packets destined to a device and, limiting of address
and routing visibility to reduce exposure to limit core network --
that is provider (P) and provider edge (PE) infrastructure --
attacks. This document is targeted at network operators seeking to
limit their exposure to risks associated with denial of service
targeting the infrastructure. These techniques are designed to be
used in addition to specific protocol or application security
features implemented in network devices.
Infrastructure protection is a complex topic. While the best
practices outlines in this document do not provide perfect
protection, they can significantly improve the protection of the
network infrastructure.
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2. Overview of Infrastructure Protection Techniques
This section provides an overview of recommended techniques that may
be used to protect network infrastructure. The details of each area,
along with some deployment consideration, are described in detail in
subsequent sections. The four technique describes in this document
are: - Edge Infrastructure Access Control List - Edge Remarking -
Device and Element Protection - Infrastructure Hiding The above list
is not exhaustive; other mechanisms can be used to provide additional
protection. The techniques discussed in this document have been
widely deployment and have proven operational security benefits in
large networks.
2.1. Edge Remarking
Edge Remarking, detailed in section 4, ensures that ingress IP
precedence or DSCP values match expected values within the context of
security. This provides another layer of defense, particularly for
traffic permitted through any of the Edge Infrastructure Access
Control Lists. This document focuses only on using Edge Remarking
best practices to enforce security policies.
2.2. Device and Element Protection
Each network infrastructure device should enforce local rules for
traffic destined to the device itself. These rules can take the form
of filters (permit/deny) or rate limiting rules that allow ingress
traffic at specified rates. These should complement any existing
Edge Infrastructure Access Control Lists and are described in more
detail in section 5. The deployment of these local device protection
rules complements the edge techniques by protecting the device from
traffic that: i) was permitted but violates device policy, ii) could
not be filtered at the edge, iii) entered the network on an interface
that did not have ingress filtering enabled.
2.3. Infrastructure Hiding
Hiding the infrastructure of the network provides an elegant
mechanism for protecting the network infrastructure. If the
destination of an attack is to an infrastructure address that is
unreachable, attacks become far more difficult. Infrastructure
hiding can be achieved in several ways: - MPLS techniques - IGP
configuration - Route advertisement control Section 6 covers
infrastructure hiding techniques.
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3. Edge Infrastructure Access Control Lists
Edge Infrastructure Access Control Lists (EIACLs) are a specific
implementation of the more general Ingress Access List. As opposed
to generic ingress filtering which denies data (sometimes referred to
as user) plane traffic, edge infrastructure access control lists do
not attempt to deny transit traffic; rather, this form of access
control limits traffic destined to infrastructureequipment while
permitting -- if needed, explicitly -- traffic through the network.
3.1. Constructing the Access List
Edge Infrastructure Access Control Lists permit only required traffic
destined to the network infrastructure, while allowing data plane
traffic to flow through unfiltered. The basic premise of EIACLs is
that only a relatively limited subset of traffic, sourced from
outside an AS, needs to be destined towards a core router and that by
explicitly permitting only that known and understood traffic, the
core devices are not subjected to unnecessary traffic that might
result in a denial of service. Since edge infrastructure access
control lists protect only the infrastructure, the development of the
list differs somewhat from "traditional" access filter lists:
1. Review addressing scheme, and identify address block(s) that
represent core devices.
2. Determine what traffic must be destined to the core devices from
outside the AS.
3. Create a filter that allow the required traffic, denies all
traffic destined to the core address block and then finally,
permits all other traffic.
As with other ingress filtering techniques, EIACLs are applied on
ingress interfaces, as close to the edge as possible. Comprehensive
coverage (i.e. on as many interface as possible) yields the most
protection.
3.2. Other Traffic
In addition to the explicitly permitted traffic, EIACLs can be
combined with other common edge filters such as: 1. Source spoof
prevention (as per RFC 3704) by denying internal AS addresses as
external sources. 2. Filtering of reserved addresses (e.g. rfc1918
addresses) as traffic should not be sourced from reserved address. 3.
Other unneeded or unnecessary traffic Filtering this traffic can be
part of the list explicitly or implicitly; explicit filters often
provide log-able information that can be of use during a security
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event.
3.3. Edge Infrastructure Conclusion
Edge Infrastructure Access Control Lists provide a very effective
first line of defense. EIACLs are not perfect and cannot protect the
network against every attack. Furthermore, to be manageable, EIACLs
must be able to clearly and simply identify infrastructure address
space. To be effective, the EIACLs should be deployed as widely as
possible at the edge of the network on devices that support the
required filtering performance characteristics.
4. Edge Rewrite/Remarking
RFC 1812 section 5.3 defines the use of IP Preference in IPv4 packets
for routing, management and control traffic. In addition, the RFC
recommends that devices use a mechanism for providing preferential
forwarding for packets marked as routing, management or control
traffic using IP Preference bits 6 or 7 (110 or 111 in binary.)
RFC2474 defines DSCP and the compatibility of IP Preference bits when
using DSCP. All packets received by customer- and peer-facing
Provider Edge (PE) router interfaces with IP Preference values of 6
or 7 or DSCP bits of 11xxxx, as specified in RFC2474 Differentiated
Services Field Definition, should have the IP Preference bits
rewritten. Routing traffic received from customer- and peer-facing
interfaces can safely have the IP Preference bits rewritten because
only a limited number of protocols are transmitted beyond the first
PE router. The bits may be rewritten to any value other than IP
Preference values 6 or 7, or any DSCP value other than 11xxxx. The
new value can be based on the network operators IP Preference or DSCP
policy. If no policy exists the bits should be rewritten to 0.
In cases where control, management, and routing traffic enters the
provider network via the customer- and peer-facing interfaces policy
should be employed to ensure proper prioritization of critical
traffic. EIACLs maybe be used facilitate the proper classification
of traffic. To offer fully transparent service, a provider may not
wish to modify the IP precedence on transit traffic through the
network. If a provider has alternate means of applying different
prioritization to router management and control traffic and transit
traffic then rewriting IP precedence bits is not required.
4.1. Edge Rewrite/Remarking Discussion
By default router vendors do not differentiate an interface on a PE
router connected to a P router from an interface connected to a CE
router. As a result any packet with the proper IP Preference or DSCP
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bits set may receive the same preferential forwarding behavior as
legitimate routing, management, and control traffic. A malicious
attack may be able to take advantage of the vulnerability to increase
the effectiveness of the attack or to attack the routing, management,
and/or control traffic directly. This document is aimed at
protecting network infrastructure from traffic to the device rather
than traffic through the device. Even though the edge rewrite/
remarking deals primarily with traffic through a device it is
included because the traffic has a direct impact on traffic to a
device. The forwarding prioritization given to routing, management,
and control traffic by default leaves devices vulnerable to indirect
attacks to the infrastructure. By rewriting the IP Precedence at the
PE protection is provided for both traffic through the network along
with traffic that is to the network that is not blocked by other
methods discussed in this document. This document assumes that all
customer- and peer-facing interfaces cannot be trusted for inter-
domain diff-serv. In cases where a trust relationship exists for
inter-domain diff-serv, diff-serv bits 1xxxxxxx do not have to be
rewritten.
4.2. Edge Rewriting/Remarking Performance Considerations
Device resources required must be taken into consideration when
rewriting/remarking IP Precedence/DSCP bits. Devices may require
additional resources to rewrite/remark packets.
5. Device/Element Protection
Even with the widest possible deployment of the techniques described
above in the section Infrastructure Edge Access Control, the
individual devices of the network must implement access control
mechanisms. This is required because, in addition to the case of
incomplete or imperfect deployment of edge infrastructure control,
threats may coem from from trusted sources within the perimeter of
the network.
5.1. Service Specific Access Control
Typically these mechanisms are not directly concerned with protecting
the availability of the device as a whole, but the device from
exploitation via the service concerned. Analysis of the behavior of
widly deployed serivce security features shows that maximizing the
security of the particular service, not overall system availability,
is the primary goal of the feature. There are many practical
examples of vendor specific security mechanisms, the references
section provides likes to several of them. These should guide the
operator in securing the services that they enable.
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5.1.1. Common Services
While each service implemented by network equipment manufacturers
differs in its available security features there are some common
services and security features for those services that have been
widely deployed. The most important first step for the operator is
to disable any unneeded/unused services. This reduces the devices
profile. If the device is not listening to a port, it is much more
difficult to attack via that port. Second, the operator should
utilize the services access control mechanisms to limit the access to
the devices service to only required sources. Examples of per serive
security are using virtual terminal access control lists, or SNMP
Community access control lists.
5.2. Aggregate Device Access Control
The device must be protected from denial of service threats, in
addition, aggregating the security policy -- as opposed to defining
it on a per service basis -- allows for a simplified view of the
access policies traffic going to the device. A key requirement of
these mechanisms is that it must not impact transit data plane
traffic.
5.2.1. IP Fragments
Traffic destined to a router is not typically fragmented. Use of
mechanisms to deny fragments to the device are recommended.
5.2.2. Performance Considerations
Care should be taken to understand a vendors implementation of
aggregate device access control and to make sure that device
operation is not impaired during DoS attacks against the device.
5.2.3. Access Control Implementation Guide
Implementing a complex set of access controls for all traffic going
to and from a router is non trivial. The following is a recommended
set of steps that has been used successfully by many carriers.
1. Develop list of required protocols.
2. Develop source address requirements: Determine destination
interface on router Does the protocol access a single interface?
Does the protocol access many interfaces? Does the protocol
access a virtual or physical interfaces?
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3. Prior to implementing with a deny, it is recommended to test the
behavior with the action of "log" and observe the results
4. Deployment should be an iterative process: Start with relatively
open lists then tighten as needed
5.3. Device Access Authorization and Accounting
Operators should use per command authorization and accounting
wherever possible. Aside from their utility in mitigating other
security threats, they provide an invaluable tool in the post event
forensics.
6. Infrastructure Hiding
While core equipment is in the transit path it is necessarily
reachable and succeptible to attacks that fall beyond the scope of
this document. Primarily, transit equipment is always at risk for
collateral damage when hosts downstream come under substantial
attack. Hiding the infrastructure of the network provides an elegant
mechanism for protecting the network infrastructure. If the an
attack vector requires that packets are sent to infrastructure
address that is unreachable, successful execution of such attacks
becomes far more difficult. The following sections present different
options for accomplishing infrastructure hiding.
6.1. Use Less IP
One way to reduce exposure of network infrastructure is to use
unnumbered links wherever possible. This is particularly useful for
customers in the simple case of a single provider with a default path
to the Internet. Not only can such a configuration reduce the
exposure of the equipment on both ends of the link to malicious
attack, the overall effort required to manage a link can be reduced
considerably with a simplified configuration and without the
additional overhead and expense of managing the addresses.
6.2. MPLS Techniques
While it may not be feasible to hide the entire infrastructure of
large networks from edge to edge using MPLS, it is certainly possible
to reduce exposure of critical core infrastructure beyond the first
hop by creating an MPLS mesh where TTL is not decremented as packets
pass through it. In this manner the number, addresses, and even
existence of intermediary devices can be hidden from traffic as it
passes through the core.
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6.3. IGP Configuration
Using a non-IP control plane for the core routing protocol can
substantially reduce the number of IP addresses that comprise (and
therefore, expose) the core. This simplifies the task of maintaining
edge ACLs or route announcement filters. IS-IS is an elegant and
mature protocol that may be suitable for this task.
6.4. Route Advertisement Control
6.4.1. Route Announcement Filtering
Inasmuch as it is unavoidable that some network elements must be
configured with IP addresses, it may be possible to assign these
address out of netblocks for which the routing advertisement can be
filtered out, thereby limiting possible sources of traffic to core
netblocks down to customers for whom you provide a default route, or
direct peers who would make the effort to create a static route for
your core netblock into your AS. By assigining address for network
infrastructure out of a limited number of address blocks which are
well known to internal network administrators, the operator can
greatly simplify ACL configuration. This can also minimise the
frequency with which ACLs need to be updated based on changes in the
network. This can also have performance implications, especially for
equipment where the length of ACLs is limited. By keeping ACLs short
they may be deployable on a wider range of existing equipment.
Further, it may be possible in those situations where customer point-
to-point links must be numbered, to address such links out of another
range of addresses for which announcements could be similarly
filtered. While this has implications for a customer's ability to
remote-monitor their circuit, this can often be overcome with
application of an address from the customer's routed space to the CPE
loopback.
6.4.2. Address Core Out of RFC 1918 Space
In addition to filtering the visibility of core addresses to the
wider Internet, it may be possible to use rfc1918 netblocks for
numbering infrastructure when IP addresses are required (eg,
loopbacks). This added level of obscurity takes prevention of wide
distribution of your infrastructure address space one step further.
Many networks filter out packets with rfc1918 address at ingress/
egress points as a matter of course. In this circumstance, tools
such as traceroute can work through your core, but reverse-
resolution of descriptive names should be restricted to queries from
internal/support groups.
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6.5. Further obfuscation
The strategy of changing services to run on ports different from the
default and well-known ones will not protect you from a determined
attacker. It can, however, provide some level of protection from
many attack tools, worms, auto-rooters, etc. Should they find access
to the infrastructure equipment in some way. Again, this does
nothing to restrict access, nor to make network devices more
difficult to reach. As with the other methods, a careful
consideration of how much effort and management each strategy
requires must be weighed against the protection that it provides and
the necessity of that protection in light of all measures taken to
protect a network.
7. IPv6
IPv6 Networks contain the same infrastructure security risks as IPv4.
All techniques described in this document for IPv4 should be directly
applicable to IPv6 networks. Limitations exist where devices do not
have feature parity between IPv4 and IPv6. Different techniques
maybe required where IPv4 and IPv6 networks deviate in
implementation. Multi-vendor networks create greater difficulties
when each vendor does not have feature parity with each other.
Hardware differences in devices that support both IPv4 and IPv6 must
also be taken into consideration. Because IPv6 uses a longer address
space the scaling, and performance characteristics of ACLs maybe
lower for IPv6 vs IPv4. The fields or number of fields that an ACL
can match on may also differ. The fact that all PE devices do not
support all the recommended ipv6 security features should not
preclude the implementation of the recommendations in this document
on the devices that do support the security features. With the
number of Network Operators deploying IPv6 growing, along with the
continued availability of IPv6 Tunnel services, connecting to the
IPv6 internet is less difficult. Dual stack IPv6 networks run on
10Gbps and greater backbones with edge speeds equal to IPv4. Neither
the edge nor the core limit potential IPv6 attacks.
7.1. Use LIPv6 Edge Infrastructure Access Control Lists
The same process should be used for constructing the IPv6 eiacl as
the IPv4 EIACL.
7.2. IPv6 Edge Remarking
IPv6 DSCP bits should be rewritten in the same manner that IPv4 DSCP
bits. Differences between DSCP rewriting of IPv4 and IPv6 will
minimal except in cases where the device capabilities differ between
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IPv4 and IPv6.
7.3. IPv6 Device and Element Protection
Device and Element protection should be created using the same
methods described in this document for IPv4. The policy may differ
for IPv6 from IPv4 in cases where services are exclusively IPv4 or
exclusively IPv6. Services not used with IPv6 should be disabled.
7.4. IPv6 Infrastructure Hiding
Network operators may deploy IPv4 differently from IPv6 in their
network. Providers may use native forwarding for IPv6 while using
MPLS for IPv4, other combinations. IPv6 infrastructure hiding should
have parity with IPv4 infrastructure hiding even if the technique
used is different. Implementation of IPv6 route advertisement
control for infrastructure hiding is difficult when using global
address space. Registeries assign fewer large blocks of IPv6 space
compared to IPv4. Providers cannot control the announcement of
infrastructure global IPv6 blocks for infrastructure hiding without
deaggregating their IPv6 announcements.
8. IP Multicast
IP Multicast behaves differently from IP unicast therefore must be
secured in a different manner. Some of the protocols used with
Multicast rely on IP unicast to transport the routing, and control
information. Unicast based protocols should be secured using the
technique described in much of this document. Because this document
is focused on hardening a service providers infrastructure rather
than validating routing announcements, much of IP Multicast filtering
will be better covered in other documents. In much the same way a
host must listen on a certain IP address and port for an IP unicast
connection, Multicast must join a group in order to receive any
information via Multicast. The major difference is that multicast
groups are global and not assigned to a specific customer or end
user. Administrative boundaries and scope are created to isolate
Multicast groups within one network or desired area.
8.1. Multicast Group Protection
Certain Multicast groups should never be joined from outside an
operators network or administrative boundary. Filters should be
placed on the protocols used to communicate with external hosts and
networks. IGMP should have a join filter to prevent hosts from
joining internal groups. MSDP should be configured with a Source
Address (SA) filter to prevent other networks from joining internal
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groups. EIACLs should include administratively bounded multicast
groups, along with any groups used for protocols internal to a
providers network. When constructing router Access Control as
described in section 5.2.4, multicast protocols must be taken into
consideration.
8.2. Performance Considerations
Multicast protocols and implementation have different performance and
scaling limitation than IP unicast. Multicast users create state on
the router every time the user joins a group. Router resources can
be exhausted if the amount of state created exceeds the resources
available on the router. Placing limits on the resources used by the
Multicast protocols can prevent collateral damage to services other
than Multicast on a router. MSDP should have a limit placed on the
number of SA announcements received. A fixed limit should be placed
on the number of entries the router stores in the IP Multicast
routing table. The number of SAP entries should have a limit placed
on them.
8.3. IPv6 and Multicast
IPv6 Multicast policy should be consistent with the IP Multicast
policy.
9. Security Considerations
This entire document is concerned with security.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
10.2. Informative References
[RFC2334] "Guidelines for Writing an IANA Considerations Section in
RFCs", October 1998.
[RFC3667] "IETF Rights in Contributions", February 2004.
[RFC3668] "Intellectual Property Rights in IETF Technology",
February 2004.
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Authors' Addresses
James Gill
Verizon Business
22001 Louden County Parkway
Ashburn, VA 20147
US
Phone: +1-703-886-3834
Email: james.gill@verizonbusiness.com
URI: www.verizonbusiness.com
Darrel Lewis
Cisco Systems Inc.
170 West Tasman Dr.
San Jose, CA 95134
US
Phone: +1-408-853-3653
Email: darlewis@cisco.com
URI: www.cisco.com
Paul Quinn
Cisco Systems Inc.
170 West Tasman Drive
San Jose, CA 95134
US
Phone: +1-408-527-3560
Email: paulq@cisco.com
URI: www.cisco.com
Peter Schoenmaker
NTT America
101 Park Ave., FL 41
New York, NY 10178
US
Phone: +1-202-808-2298
Fax:
Email: pds@ntt.net
URI:
Gill, et al. Expires March 4, 2007 [Page 15]
Internet-Draft Infrastructure Security August 2006
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Gill, et al. Expires March 4, 2007 [Page 16]
