< draft-richardson-opsawg-mud-acceptable-urls-01.txt		draft-richardson-opsawg-mud-acceptable-urls-02.txt >
	OPSAWG Working Group M. Richardson		OPSAWG Working Group M. Richardson
	Internet-Draft Sandelman Software Works		Internet-Draft Sandelman Software Works
	Updates: 8520 (if approved) W. Pan		Updates: 8520 (if approved) J. Yang
	Intended status: Best Current Practice Huawei Technologies		Intended status: Best Current Practice Huawei Technologies Co., Ltd.
	Expires: December 17, 2020 E. Lear		Expires: March 26, 2021 E. Lear
	Cisco Systems		Cisco Systems
	June 15, 2020		September 22, 2020
	Authorized update to MUD URLs		Authorized update to MUD URLs
	draft-richardson-opsawg-mud-acceptable-urls-01		draft-richardson-opsawg-mud-acceptable-urls-02
	Abstract		Abstract
	This document provides a way for an RFC8520 Manufacturer Usage		This document provides a way for an RFC8520 Manufacturer Usage
	Description (MUD) definitions to declare what are acceptable		Description (MUD) definitions to declare what are acceptable
	replacement URLs for a device.		replacement URLs for a device.
	Status of This Memo		Status of This Memo
	This Internet-Draft is submitted in full conformance with the		This Internet-Draft is submitted in full conformance with the
	skipping to change at page 1, line 35 ¶		skipping to change at page 1, line 35 ¶
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts is at https://datatracker.ietf.org/drafts/current/.		Drafts is at https://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	This Internet-Draft will expire on December 17, 2020.		This Internet-Draft will expire on March 26, 2021.
	Copyright Notice		Copyright Notice
	Copyright (c) 2020 IETF Trust and the persons identified as the		Copyright (c) 2020 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents		Provisions Relating to IETF Documents
	(https://trustee.ietf.org/license-info) in effect on the date of		(https://trustee.ietf.org/license-info) in effect on the date of
	publication of this document. Please review these documents		publication of this document. Please review these documents
	skipping to change at page 2, line 17 ¶		skipping to change at page 2, line 17 ¶
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
	2. Updating MUD URLs vs Updating MUD files . . . . . . . . . . . 3		2. Updating MUD URLs vs Updating MUD files . . . . . . . . . . . 3
	2.1. Updating the MUD file in place . . . . . . . . . . . . . 3		2.1. Updating the MUD file in place . . . . . . . . . . . . . 3
	2.1.1. Adding capabilities . . . . . . . . . . . . . . . . . 3		2.1.1. Adding capabilities . . . . . . . . . . . . . . . . . 3
	2.1.2. Removing capabilities . . . . . . . . . . . . . . . . 4		2.1.2. Removing capabilities . . . . . . . . . . . . . . . . 4
	2.1.3. Significant changes to protocols . . . . . . . . . . 4		2.1.3. Significant changes to protocols . . . . . . . . . . 4
	2.2. Motivation for updating MUD URLs . . . . . . . . . . . . 5		2.2. Motivation for updating MUD URLs . . . . . . . . . . . . 5
	3. Threat model for MUD URLs . . . . . . . . . . . . . . . . . . 5		3. Threat model for MUD URLs . . . . . . . . . . . . . . . . . . 5
	3.1. leveraging the manufacturer signature . . . . . . . . . . 5		3.1. Trust on First Use (TOFU): leveraging the manufacturer
			signature . . . . . . . . . . . . . . . . . . . . . . . . 5
	3.2. Concerns about same-signer mechanism . . . . . . . . . . 5		3.2. Concerns about same-signer mechanism . . . . . . . . . . 5
	4. Changes to RFC8520 . . . . . . . . . . . . . . . . . . . . . 5		4. Outline of proposed mechanism . . . . . . . . . . . . . . . . 6
	5. Privacy Considerations . . . . . . . . . . . . . . . . . . . 6		5. Changes to RFC8520 . . . . . . . . . . . . . . . . . . . . . 6
	6. Security Considerations . . . . . . . . . . . . . . . . . . . 7		6. Privacy Considerations . . . . . . . . . . . . . . . . . . . 7
	7. References . . . . . . . . . . . . . . . . . . . . . . . . . 7		7. Security Considerations . . . . . . . . . . . . . . . . . . . 8
	7.1. Normative References . . . . . . . . . . . . . . . . . . 7		8. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
	7.2. Informative References . . . . . . . . . . . . . . . . . 8		8.1. Normative References . . . . . . . . . . . . . . . . . . 8
	Appendix A. Appendices . . . . . . . . . . . . . . . . . . . . . 8		8.2. Informative References . . . . . . . . . . . . . . . . . 9
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8		Appendix A. Appendices . . . . . . . . . . . . . . . . . . . . . 9
			Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
	1. Introduction		1. Introduction
	[RFC8520] provides a standardized way to describe how a specific		[RFC8520] provides a standardized way to describe how a specific
	purpose device makes use of Internet resources. Access Control Lists		purpose device makes use of Internet resources. Access Control Lists
	(ACLs) can be defined in an RFC8520 Manufacturer Usage Description		(ACLs) can be defined in an RFC8520 Manufacturer Usage Description
	(MUD) file that permit a device to access Internet resources by DNS		(MUD) file that permit a device to access Internet resources by DNS
	name.		name.
	MUD URLs can come from a number of sources:		MUD URLs can come from a number of sources:
	skipping to change at page 4, line 13 ¶		skipping to change at page 4, line 15 ¶
	controller only.		controller only.
	Useful and needed upgrades to the firmware could add credentials to		Useful and needed upgrades to the firmware could add credentials to
	that service, permitting it to be opened up for more general access.		that service, permitting it to be opened up for more general access.
	The new MUD file would provide for such access, but when combined		The new MUD file would provide for such access, but when combined
	with the weak security of the old firmware, results in a compromised		with the weak security of the old firmware, results in a compromised
	device.		device.
	While there is an argument that old firmware was insecure and should		While there is an argument that old firmware was insecure and should
	be replaced, it is often the case that the upgrade process involves		be replaced, it is often the case that the upgrade process involves
	downtown, or can introduce risks due to needed evaluations not having		downttime, or can introduce risks due to needed evaluations not
	been completed yet. As an example: moving vehicles (cars, airplanes,		having been completed yet. As an example: moving vehicles (cars,
	etc.) should not perform upgrades while in motion. It is probably		airplanes, etc.) should not perform upgrades while in motion! It is
	undesireable to perform any upgrade to an airplane outside of its		probably undesireable to perform any upgrade to an airplane outside
	service facility. The owner of a vehicle may desire to only perform		of its service facility. The owner of a vehicle may desire to only
	software upgrades when they are at home, and could make other		perform software upgrades when they are at home, and could make other
	arrangements for transporation, rather than when parked at a remote		arrangements for transporation, rather than when parked at a remote
	cabin. The situation for medical devices is even more complex.		cabin. The situation for upgrades of medical devices has even more
			considerations involving regulatory compliance.
	2.1.2. Removing capabilities		2.1.2. Removing capabilities
	For situations where existing capabilities prove to be a problem and		For situations where existing capabilities prove to be a problem and
	are to be turned off or removed in subsequent versions of the		are to be turned off or removed in subsequent versions of the
	firmware, the MUD file will be updated to disallow connections that		firmware, the MUD file will be updated to disallow connections that
	previously were allowed.		previously were allowed.
	In this case, the new MUD file will forbid some connection which the		In this case, the new MUD file will forbid some connection which the
	old firmware still expects to do. As explained in the previous		old firmware still expects to do. As explained in the previous
	section, upgrades may not always occur immediately upon release of		section, upgrades may not always occur immediately upon release of
	the new firmware.		the new firmware.
	In this case the old device will be performing unwanted connections,		In this case the old device will be performing unwanted connections,
	and the MUD controller when be alerting the device owner that the		and the MUD controller when be alerting the device owner that the
	device is mis-behaving. This causes a [boycrieswolf] situation,		device is mis-behaving. This causes a false positive situation (see
	leading to real security issues being ignored. This is a serious		[boycrieswolf]), leading to real security issues being ignored. This
	issue as documented also in [boywolfinfosec], and [falsemalware].		is a serious issue as documented also in [boywolfinfosec], and
			[falsemalware].
	2.1.3. Significant changes to protocols		2.1.3. Significant changes to protocols
	[I-D.reddy-opsawg-mud-tls] suggests MUD definitions to allow		[I-D.reddy-opsawg-mud-tls] suggests MUD definitions to allow
	examination of TLS protocol details. Such a profile may be very		examination of TLS protocol details. Such a profile may be very
	specific to the TLS library which is shipped. Changes to the library		specific to the TLS library which is shipped in a device. Changes to
	(including bug fixes) may cause significant changes to the profile,		the library (including bug fixes) may cause significant changes to
	requiring changes to the profile described in the MUD file. Such		the profile, requiring changes to the profile described in the MUD
	changes are likely neither forward nor backward compatible with other		file. Such changes are likely neither forward nor backward
	versions, and in place updates to MUD files is not indicated.		compatible with other versions, and in place updates to MUD files are
			therefore not indicated.
	2.2. Motivation for updating MUD URLs		2.2. Motivation for updating MUD URLs
	While many small tweaks to a MUD file can be done in place, the		While many small tweaks to a MUD file can be done in place, the
	situation described above, particularly when it comes to removing		situation described above, particularly when it comes to removing
	capabilities will require updates to the MUD URL. A strategy is do		capabilities will suggests that changes to the MUD URL. A strategy
	this securely is needed, and the rest of this document provides a		is do this securely is needed, and the rest of this document provides
	mechanism to do this securely.		a mechanism to do this securely.
	3. Threat model for MUD URLs		3. Threat model for MUD URLs
	Only the DHCP and LLDP MUD URL mechanisms are sufficiently close to		Only the DHCP and LLDP MUD URL mechanisms are sufficiently close to
	the firmware version that they can be easily updated when the		the firmware version that they can be easily updated when the
	firmware is updated. Because of that sensitivity, they are also		firmware is updated. Because of that sensitivity, they may also be
	easily changed by malware.		easily changed by malware!
	There are mitigating mechanisms which may be enough. The MUD files		There are mitigating mechanisms which may be enough to deal with this
	are signed by the manufacturer. [RFC8520] has not established a		problem when MUD files are signed by the manufacturer.
	trust model for MUD controllers to determine whether a signature from
	a specific entity is legitimate as a signature for a particular
	device. [RFC8520] leaves this to the industry to work out.
	3.1. leveraging the manufacturer signature		It should be noted that [RFC8520] has not established a trust model
			for MUD controllers to determine whether a signature from a specific
			entity is legitimate as a signature for a particular device.
			[RFC8520] leaves this to the industry to work out through supply
			chain arrangements or other heuristics.
	Many MUD controllers currently use a Trust on First Use mechanism		3.1. Trust on First Use (TOFU): leveraging the manufacturer signature
	where the first time a signature from a device is verified, the
	signatory is recorded. Subsequent updates to that MUD file MUST be		Many MUD controllers currently use a Trust on First Use (TOFU)
	signed by the same entity to be accepted.		mechanism. The first time a signature from a particular device-type
			is verified, the identity of the signing authority is recorded. It
			is pinned. Subsequent updates to that MUD file must be signed by the
			same entity in order to be accepted.
	Based upon this process, an update to the MUD URL would be valid if		Based upon this process, an update to the MUD URL would be valid if
	the new MUD file was signed by the same entity that signed the		the new MUD file was signed by the same entity that signed the
	previous entry. This mechanism permits a replacement URL to be any		previous entry. This mechanism permits a replacement URL to be any
	URL that the same manufacturer can provide.		URL that the same manufacturer can provide.
	3.2. Concerns about same-signer mechanism		3.2. Concerns about same-signer mechanism
	There is still a potential threat: a manufacturer which has many		There is still a potential threat: a manufacturer which has many
	products may have a MUD definition for another product that has the		products may have a MUD definition for another product that has the
	privileges that the malware desires.		privileges that the malware desires.
	4. Changes to RFC8520		The malware could simply change the expressed MUD URL to that of the
			other product, and it will be accepted by the MUD controller as
			valid.
			This works as long as manufacturers use a single key to sign all
			products. Some manufacturers could sign each product with a
			different key. Possibly, all the keys are collected into a single
			PKI, signed by a common certification authority. In this case, the
			question as to whether the MUD controller should pin the end-entity
			(EE) certificate, or the CA certificate. Pinning the EE certificate
			defends against malware that changes the product type, but keeps the
			manufacturer from being able to cycle the validity of the End-Entity
			Certificate for cryptographic hygiene reasons. Pinning the CA
			certificate allows the EE certificate to change, but may not defend
			against product type changes.
			It is possible to invent policy mechanisms that would link the EE
			certificate to a value that is in the MUD file. This could be a
			policy OID, or could involve some content in a subjectAltName.
			Future work could go in this direction. This document proposes a
			simpler solution.
			4. Outline of proposed mechanism
			The document proposes to limit what MUD URLs are considered valid
			from the device, limiting new MUD URLs to be variations of the
			initial (presumed to be secure) URL.
			5. Changes to RFC8520
	The first MUD file which is defined for a device can come from an		The first MUD file which is defined for a device can come from an
	IDevID, or via Trust on First Use with DHCP or LLDP or another		IDevID (which is considered more secure), or via Trust on First Use
	mechanism.		with DHCP or LLDP or another mechanism.
	This first, initially trusted, MUD file will be called the "root" MUD		This first, initially trusted, MUD file will be called the "root" MUD
	file.		file.
	MUD files contain a self-referential MUD-URL attribute that point to		MUD files contain a self-referential MUD-URL attribute that point to
	a MUD file located on the vendor's web site. While the IDevID, DHCP		a MUD file located on the vendor's web site. While the IDevID, DHCP
	and LLDP mechanisms only transmit a URL, there are some newer, not		and LLDP mechanisms only transmit a URL, there are some newer, not
	yet standardized proposals that would transmit an entire MUD file.		yet standardized proposals that would fetch an entire MUD file from
			the device, such as [I-D.jimenez-t2trg-mud-coap].
	The MUD-URL MUST always be an Absolute URI: see [RFC3986] section		The MUD-URL MUST always be an Absolute URI: see [RFC3986] section
	4.3.		4.3.
	The URL found in the MUD-URL attribute is to be called the canonical		The URL found in the MUD-URL attribute is to be called the canonical
	MUD URL for the device.		MUD URL for the device.
	The MUD-SIGNATURE attribute in the MUD file SHOULD be a relative URI		The MUD-SIGNATURE attribute in the MUD file SHOULD be a relative URI
	(see [RFC3986] section 4.2) with the (hierarchical) base URL for this		(see [RFC3986] section 4.2) with the (hierarchical) base URL for this
	reference being the MUD-URL attribute.		reference being the MUD-URL attribute.
	Subsequent MUD files are considered valid if:		Subsequent MUD files are considered valid if:
	o have the same initial Base-URI as the MUD-URL, but may have a		o have the same initial Base-URI as the MUD-URL, but may have a
	different final part		different final part
	o they are signed by the same End Entity (same trusted CA and same		o they are signed by the same End Entity (same trusted CA and same
	SubjectAltName) as the "root" MUD file		SubjectAltName) as the "root" MUD file.
	Section 5.2 of [RFC3986] details many cases for calculating the Base-		Section 5.2 of [RFC3986] details many cases for calculating the Base-
	URI. The test is simplified to: remove everything to the right of		URI. The test is simplified to: remove everything to the right of
	the last (rightmost) "/" in the URL of "root" MUD file URL, and the		the last (rightmost) "/" in the URL of "root" MUD file URL, and the
	proposed new URL. The resulting two strings MUST be identical.		proposed new URL. The resulting two strings MUST be identical.
	For as a simple example, if the "root" mud-url is		For as a simple example, if the "root" mud-url is
	http://example.com/hello/there/file.json then any URL that starts		http://example.com/hello/there/file.json then any URL that starts
	with http://example.com/hello/there/ would be acceptable, such as		with http://example.com/hello/there/ would be acceptable, such as
	http://example.com/hello/there/revision2.json.		http://example.com/hello/there/revision2.json.
	Once the new MUD file is accepted, then it becomes the new "root" MUD		Once the new MUD file is accepted, then it becomes the new "root" MUD
	file, and any subsequent updates must be relative to the MUD-URL in		file, and any subsequent updates must be relative to the MUD-URL in
	that file. This process allows a manufacturer to rework their file		the new file.
	structure, to change web server hostnames (such as when there is an
	acquisition or merger), etc. so long as they retain the old structure
	long enough for all devices to upgrade at least once.
	5. Privacy Considerations		This process allows a manufacturer to rework their file structure, to
			change web server hostnames (such as when there is an acquisition or
			merger), etc. so long as they retain the old structure long enough
			for all devices to upgrade at least once.
			(XXX: how should the trust anchor for the signature be updated when
			there is Merger&Acquisition)
			6. Privacy Considerations
	The MUD URL contains sensitive model and even firmware revision		The MUD URL contains sensitive model and even firmware revision
	numbers. Thus the MUD URL identifies the make, model and revision of		numbers. Thus the MUD URL identifies the make, model and revision of
	a device. [RFC8520] already identifies this privacy concern, and		a device. [RFC8520] already identifies this privacy concern, and
	suggests use of TLS so that the HTTP requests that retrieve the MUD		suggests use of TLS so that the HTTP requests that retrieve the MUD
	file do not divulge that level of detail. However, it is possible		file do not divulge that level of detail. However, it is possible
	that even observing the traffic to that manufacturer may be		that even observing the traffic to that manufacturer may be
	revealing, and [RFC8520] goes on to suggest use of a proxy as well.		revealing, and [RFC8520] goes on to suggest use of a proxy as well.
	6. Security Considerations		7. Security Considerations
	Prior to the standardization of the process in this document, if a		Prior to the standardization of the process in this document, if a
	device was infiltrated by malware, and said malware wished to make		device was infiltrated by malware, and said malware wished to make
	accesses beyond what the current MUD file allowed, the the malware		accesses beyond what the current MUD file allowed, the the malware
	would have to: 1. arrange for an equivalent MUD file to be visible		would have to: 1. arrange for an equivalent MUD file to be visible
	somewhere on the Internet 2. depend upon the MUD-manager either not		somewhere on the Internet 2. depend upon the MUD-manager either not
	checking signatures, or 3. somehow get the manufacturer to sign the		checking signatures, or 3. somehow get the manufacturer to sign the
	alternate MUD 4. announce this new URL via DHCP or LLDP, updating the		alternate MUD 4. announce this new URL via DHCP or LLDP, updating the
	MUD-manager with the new permissions.		MUD-manager with the new permissions.
	skipping to change at page 7, line 44 ¶		skipping to change at page 8, line 42 ¶
	A manufacturer which has not managed their MUD files in the the way		A manufacturer which has not managed their MUD files in the the way
	described here can deploy new directories of per-product MUD files,		described here can deploy new directories of per-product MUD files,
	and then can update the existing MUD files in place to point to the		and then can update the existing MUD files in place to point to the
	new URLs using the MUD-URL attribute.		new URLs using the MUD-URL attribute.
	There is therefore no significant flag day: MUD managers may		There is therefore no significant flag day: MUD managers may
	implement the new policy without significant concern about backwards		implement the new policy without significant concern about backwards
	compatibility.		compatibility.
	7. References		8. References
	7.1. Normative References		8.1. Normative References
	[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform		[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
	Resource Identifier (URI): Generic Syntax", STD 66,		Resource Identifier (URI): Generic Syntax", STD 66,
	RFC 3986, DOI 10.17487/RFC3986, January 2005,		RFC 3986, DOI 10.17487/RFC3986, January 2005,
	<https://www.rfc-editor.org/info/rfc3986>.		<https://www.rfc-editor.org/info/rfc3986>.
	[RFC8520] Lear, E., Droms, R., and D. Romascanu, "Manufacturer Usage		[RFC8520] Lear, E., Droms, R., and D. Romascanu, "Manufacturer Usage
	Description Specification", RFC 8520,		Description Specification", RFC 8520,
	DOI 10.17487/RFC8520, March 2019,		DOI 10.17487/RFC8520, March 2019,
	<https://www.rfc-editor.org/info/rfc8520>.		<https://www.rfc-editor.org/info/rfc8520>.
	7.2. Informative References		8.2. Informative References
	[boycrieswolf]		[boycrieswolf]
	"The Boy Who Cried Wolf", January 2020,		"The Boy Who Cried Wolf", January 2020,
	<https://fablesofaesop.com/the-boy-who-cried-wolf.html>.		<https://fablesofaesop.com/the-boy-who-cried-wolf.html>.
	[boywolfinfosec]		[boywolfinfosec]
	"Security Alerts - A Case of the Boy Who Cried Wolf?",		"Security Alerts - A Case of the Boy Who Cried Wolf?",
	January 2020, <https://www.infosecurity-		January 2020, <https://www.infosecurity-
	magazine.com/opinions/security-alerts-boy-cried-wolf/>.		magazine.com/opinions/security-alerts-boy-cried-wolf/>.
	[falsemalware]		[falsemalware]
	"False malware alerts cost organizations $1.27M annually,		"False malware alerts cost organizations $1.27M annually,
	report says", January 2020,		report says", January 2020,
	<https://www.scmagazine.com/home/security-news/false-		<https://www.scmagazine.com/home/security-news/false-
	malware-alerts-cost-organizations-1-27m-annually-report-		malware-alerts-cost-organizations-1-27m-annually-report-
	says/ and http://go.cyphort.com/Ponemon-Report-Page.html>.		says/ and http://go.cyphort.com/Ponemon-Report-Page.html>.
			[I-D.jimenez-t2trg-mud-coap]
			Jimenez, J., "Using MUD on CoAP environments", draft-
			jimenez-t2trg-mud-coap-00 (work in progress), March 2020.
	[I-D.reddy-opsawg-mud-tls]		[I-D.reddy-opsawg-mud-tls]
	Reddy.K, T., Wing, D., and B. Anderson, "MUD (D)TLS		Reddy.K, T., Wing, D., and B. Anderson, "MUD (D)TLS
	profiles for IoT devices", draft-reddy-opsawg-mud-tls-03		profiles for IoT devices", draft-reddy-opsawg-mud-tls-05
	(work in progress), January 2020.		(work in progress), August 2020.
	[I-D.richardson-opsawg-securehomegateway-mud]		[I-D.richardson-opsawg-securehomegateway-mud]
	Richardson, M., Latour, J., and H. Gharakheili, "Loading		Richardson, M., Latour, J., and H. Gharakheili, "On
	MUD URLs from QR codes", draft-richardson-opsawg-		loading MUD URLs from QR codes", draft-richardson-opsawg-
	securehomegateway-mud-03 (work in progress), March 2020.		securehomegateway-mud-05 (work in progress), September
			2020.
	Appendix A. Appendices		Appendix A. Appendices
	Authors' Addresses		Authors' Addresses
	Michael Richardson		Michael Richardson
	Sandelman Software Works		Sandelman Software Works
	Email: mcr+ietf@sandelman.ca		Email: mcr+ietf@sandelman.ca
			Jie Yang
			Huawei Technologies Co., Ltd.
	Wei Pan		Email: jay.yang@huawei.com
	Huawei Technologies
	Email: william.panwei@huawei.com
	Eliot Lear		Eliot Lear
	Cisco Systems		Cisco Systems
	Email: lear@cisco.com		Email: lear@cisco.com
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